fix(ci): copy CHANGELOG.md into the wasm docker stage — deploys broken since v0.47.0

whats_new_plugin embeds the changelog at compile time
(include_str!("../../CHANGELOG.md"), shipped 2026-07-13), but the
Dockerfile's wasm-builder stage copies an explicit file list that
never included CHANGELOG.md — every docker-build since (10 runs,
v0.48.x and v0.49.0 content) failed in build_wasm.sh while web-e2e
(full checkout) stayed green, so the web has been serving the
July 14 image.

Also add CHANGELOG.md to the workflow's trigger paths so changelog
cuts redeploy the web and the What's-new card stays fresh.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.gitea/workflows/docker-build.yml

@@ -1,4 +1,4 @@
-# Build and deploy the solitaire server Docker image.
+# Build and deploy the solitaire server Docker image. (retriggered 2026-07-16)
 name: Build and Deploy
 
 on:
@@ -15,6 +15,9 @@ on:
       - 'Cargo.toml'
       - 'Cargo.lock'
       - 'build_wasm.sh'
+      # The engine embeds CHANGELOG.md (What's-new card) — changelog cuts
+      # must redeploy the web so the card content stays fresh.
+      - 'CHANGELOG.md'
       - 'solitaire_server/Dockerfile'
       - '.gitea/workflows/docker-build.yml'
 

CHANGELOG.md

@@ -6,6 +6,116 @@ project follows [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+## [0.49.0] — 2026-07-16
+
+### Added
+
+- **See what sync did.** After every sync, the Account tab shows exactly
+  what the merge decided — a "no conflicts" note, or one line per
+  reconciled field with both values ("this device: 3 / server: 5"). When
+  a merge wasn't clean, a toast summarises it: "Synced — 2 conflicts,
+  kept newer values". (#189)
+- **One-file backup.** Settings → Account → Local data can now export
+  every save (settings, stats, achievements, progress) into a single
+  backup file next to your other saves — and restore from it later or on
+  another machine. Restores never silently reset anything: a missing or
+  incompatible backup shows an error and leaves your data untouched.
+  (#189)
+
+### Changed
+
+- Under the hood, the scheduler-ambiguity gate now covers the full
+  plugin cluster (22 plugins) — 585 undefined-order system pairs were
+  pinned or proven independent, eliminating a whole class of
+  "works-on-my-frame" bugs in modes, replays, input, and chrome. (#188)
+
+## [0.48.1] — 2026-07-15
+
+### Added
+
+- **Reduce Transparency.** Settings → Accessibility gains a toggle that
+  replaces the see-through glass toolbar with a solid panel, so cards
+  behind it can never reduce readability. High Contrast mode now also
+  makes the glass markedly more opaque with a brighter outline. (#187)
+
+### Changed
+
+- **The toolbar gets out of your way.** While you're dragging a card,
+  the floating toolbar slides off the bottom edge and returns when you
+  drop — bottom-row piles are never hidden behind it. Instant (no
+  animation) when Reduce Motion is on. (#187)
+
+## [0.48.0] — 2026-07-15
+
+### Changed
+
+- **Floating glass tab bar** (touch). The bottom action bar is now a
+  floating translucent pill — Undo, Draw, Hint, and Pause — with a
+  separate round Menu button beside it, hovering above the bottom edge
+  instead of docking to it. Draw stays expanded as the highlighted
+  action; the other buttons reveal their label while held (instantly,
+  with reduce-motion on). Same actions, same behaviour — new clothes.
+  (#186)
+- **Consistent empty, loading, and error screens.** The theme store,
+  leaderboard, and replay list now share one visual language for
+  "nothing here yet", "still loading", and "something went wrong" —
+  each with a next step instead of a dead end. (#184)
+
+### Fixed
+
+- **Hotkeys during drags.** Pressing Undo, New Game, Draw, or a mode
+  key mid-drag no longer fights the card you're holding — game-mutating
+  hotkeys are ignored until the card is dropped. (#185)
+
+## [0.47.0] — 2026-07-13
+
+### Added
+
+- **"What's new" on update.** The first launch after an update shows a
+  one-time card summarising what changed — like this one, right now.
+  Dismiss it and it never repeats; fresh installs never see it. (#180)
+- **Situational tips.** Two one-time teaches that fire from play, not a
+  tour: staring at a stuck board for a while points you at Hint, and an
+  engaged game quietly mentions the long-press quick-action menu —
+  unless you've already found it yourself. (#181)
+- **UI scale.** Settings → Accessibility now has a UI Scale control
+  (90% / 100% / 115% / 130%) that resizes every menu, button, and HUD
+  element live. The table always fits your screen regardless. (#182)
+- **Hold `/` for shortcuts** (desktop). A reference card of every
+  keyboard binding appears while `/` is held. The onboarding tour and
+  this card now share one binding table, so they can never disagree —
+  the tour's copy had drifted from reality. (#183)
+
+## [0.46.0] — 2026-07-13
+
+### Added
+
+- **Theme-store previews.** The store modal now shows each theme's
+  preview image next to its name — the server has advertised them since
+  the store launched; the client finally fetches them. Thumbnails load
+  in the background, pop in as they arrive, and are remembered for the
+  session. (#179)
+- **Hint ghost preview.** Asking for a hint now also plays a translucent
+  copy of the suggested card gliding to its destination (twice, then it
+  fades) alongside the usual highlights — you see the move, not just the
+  pieces. Automatically disabled when reduce-motion is on. (#179)
+
+### Changed
+
+- **One toast style, one place.** Queued info banners and instant
+  celebration/warning/error toasts now share a single bottom-anchored
+  stack that clears the touch action bar; simultaneous toasts stack
+  upward instead of overlapping. (#178)
+
+### Fixed
+
+- **Touch onboarding copy.** The how-to-play slide no longer tells touch
+  players to left/right-click; it now describes drag, double-tap, and
+  the bottom-bar Hint button. (#178)
+- **First launch shows one screen at a time.** On a fresh install the
+  Home screen no longer spawns underneath the welcome tour; the order is
+  now onboarding → Home → table. (#178)
+
 ## [0.45.0] — 2026-07-13
 
 ### Added

solitaire_core/src/game_state.rs

@@ -490,6 +490,32 @@ impl GameState {
         self.session.stats().stats().recycle_count()
     }
 
+    /// Number of cards moved onto foundations this game, read from the
+    /// upstream session stats. Cumulative like [`Self::recycle_count`] —
+    /// not rolled back on undo.
+    pub fn move_to_foundation_count(&self) -> u32 {
+        self.session.stats().stats().move_to_foundation_count()
+    }
+
+    /// Number of stacks moved onto tableaus (from stock or another tableau)
+    /// this game, read from the upstream session stats. Cumulative — not
+    /// rolled back on undo.
+    pub fn move_to_tableau_count(&self) -> u32 {
+        self.session.stats().stats().move_to_tableau_count()
+    }
+
+    /// Number of cards taken back off a foundation this game, read from the
+    /// upstream session stats. Cumulative — not rolled back on undo.
+    pub fn move_from_foundation_count(&self) -> u32 {
+        self.session.stats().stats().move_from_foundation_count()
+    }
+
+    /// Number of face-down cards revealed (flipped up) this game, read from
+    /// the upstream session stats. Cumulative — not rolled back on undo.
+    pub fn flip_up_count(&self) -> u32 {
+        self.session.stats().stats().flip_up_bonus_count()
+    }
+
     /// Total moves made this game (draws, recycles, and card moves), derived
     /// from the session's instruction history length.
     pub fn move_count(&self) -> u32 {

solitaire_data/src/lib.rs

@@ -133,6 +133,12 @@ pub use challenge::{CHALLENGE_SEEDS, challenge_count, challenge_seed_for};
 pub mod difficulty_seeds;
 pub use difficulty_seeds::{DifficultySeeds, seeds_for};
 
+pub mod transfer;
+pub use transfer::{
+    BundleError, DATA_BUNDLE_SCHEMA_VERSION, DataBundle, data_bundle_path, load_bundle_from,
+    save_bundle_to,
+};
+
 pub mod settings;
 pub use settings::{
     AnimSpeed, REPLAY_MOVE_INTERVAL_STEP_SECS, SOLVER_DEAL_RETRY_CAP, Settings, SyncBackend,

solitaire_data/src/settings.rs

@@ -154,6 +154,14 @@ pub struct Settings {
     /// `#[serde(default)]`.
     #[serde(default)]
     pub reduce_motion_mode: bool,
+    /// When `true`, replaces translucent "glass" chrome (the floating
+    /// touch tab bar) with opaque fills so table content behind it can
+    /// never reduce label/icon contrast. The accessibility counterpart
+    /// of iOS "Reduce Transparency". Older `settings.json` files written
+    /// before this field existed deserialize cleanly to `false` thanks
+    /// to `#[serde(default)]`.
+    #[serde(default)]
+    pub reduce_transparency_mode: bool,
     /// Window size and screen position to restore on next launch. `None`
     /// means "use platform defaults" — set on first run, then populated
     /// as the player resizes / moves the window. Older `settings.json`
@@ -257,6 +265,32 @@ pub struct Settings {
     /// deserialize cleanly to `GameMode::Classic` via `#[serde(default)]`.
     #[serde(default)]
     pub last_mode: GameMode,
+    /// The release version whose "What's new" card the player has already
+    /// seen (e.g. `"0.46.0"`). Empty on installs that predate the card,
+    /// which correctly reads as "there is news to show" after an upgrade;
+    /// fresh installs stamp it silently when onboarding completes. Older
+    /// `settings.json` files deserialize cleanly to `""` via
+    /// `#[serde(default)]`.
+    #[serde(default)]
+    pub last_seen_whats_new: String,
+    /// `true` once the one-shot "Stuck? Try a hint" contextual tip has
+    /// fired (or been suppressed as unnecessary). Phase I teach: fired
+    /// by the situation, shown once, like `shown_achievement_onboarding`.
+    #[serde(default)]
+    pub shown_stall_hint_tip: bool,
+    /// `true` once the one-shot radial-menu contextual tip has fired —
+    /// or the player has already opened the radial menu on their own,
+    /// which marks the tip as unnecessary without showing it.
+    #[serde(default)]
+    pub shown_radial_menu_tip: bool,
+    /// Global UI scale multiplier applied to all UI chrome (HUD, modals,
+    /// action bar) — the table itself stays window-fit via
+    /// `compute_layout`. Cycles through 0.9 / 1.0 / 1.15 / 1.3 in
+    /// Settings → Accessibility; clamped to `[UI_SCALE_MIN,
+    /// UI_SCALE_MAX]` by [`Settings::sanitized`]. Older `settings.json`
+    /// files deserialize cleanly to `1.0` via the serde default.
+    #[serde(default = "default_ui_scale")]
+    pub ui_scale: f32,
     /// Custom public name displayed on the leaderboard. When `None`, the
     /// player's server `username` is used instead. Trimmed to 32 characters
     /// before submission. Older `settings.json` files written before this
@@ -365,6 +399,16 @@ fn default_replay_move_interval_secs() -> f32 {
     0.45
 }
 
+/// Lowest / highest UI scale the settings row offers; anything outside
+/// (hand-edited settings.json) clamps here on load.
+pub const UI_SCALE_MIN: f32 = 0.9;
+/// See [`UI_SCALE_MIN`].
+pub const UI_SCALE_MAX: f32 = 1.3;
+
+fn default_ui_scale() -> f32 {
+    1.0
+}
+
 fn default_matomo_site_id() -> u32 {
     1
 }
@@ -415,6 +459,7 @@ impl Default for Settings {
             color_blind_mode: false,
             high_contrast_mode: false,
             reduce_motion_mode: false,
+            reduce_transparency_mode: false,
             window_geometry: None,
             selected_theme_id: default_theme_id(),
             shown_achievement_onboarding: false,
@@ -425,6 +470,10 @@ impl Default for Settings {
             replay_move_interval_secs: default_replay_move_interval_secs(),
             last_difficulty: None,
             last_mode: GameMode::Classic,
+            last_seen_whats_new: String::new(),
+            shown_stall_hint_tip: false,
+            shown_radial_menu_tip: false,
+            ui_scale: default_ui_scale(),
             leaderboard_display_name: None,
             leaderboard_opted_in: false,
             take_from_foundation: true,
@@ -460,6 +509,7 @@ impl Settings {
             replay_move_interval_secs: self
                 .replay_move_interval_secs
                 .clamp(REPLAY_MOVE_INTERVAL_MIN_SECS, REPLAY_MOVE_INTERVAL_MAX_SECS),
+            ui_scale: self.ui_scale.clamp(UI_SCALE_MIN, UI_SCALE_MAX),
             selected_theme_id,
             ..self
         }

solitaire_data/src/theme_store_client.rs

@@ -19,6 +19,10 @@ use thiserror::Error;
 /// so downloading it is pure waste.
 pub const MAX_THEME_DOWNLOAD_BYTES: u64 = 20 * 1024 * 1024;
 
+/// Hard cap on a preview PNG download — previews are small decorative
+/// thumbnails; anything past this is a misconfigured server.
+pub const MAX_PREVIEW_BYTES: u64 = 512 * 1024;
+
 /// Errors surfaced by [`ThemeStoreClient`].
 #[derive(Debug, Error)]
 pub enum ThemeStoreError {
@@ -110,6 +114,42 @@ impl ThemeStoreClient {
         verify_archive(&bytes, entry)?;
         Ok(bytes.to_vec())
     }
+
+    /// Fetch the preview PNG the catalog advertises for `entry`.
+    ///
+    /// Returns `Http(404)` when the entry carries no `preview_url` —
+    /// the same shape the server answers with when the file is absent,
+    /// so callers only handle one "no preview" case. Previews are
+    /// decorative; unlike archives they carry no checksum, only the
+    /// [`MAX_PREVIEW_BYTES`] size cap.
+    pub async fn fetch_preview(
+        &self,
+        entry: &ThemeCatalogEntry,
+    ) -> Result<Vec<u8>, ThemeStoreError> {
+        let Some(path) = entry.preview_url.as_deref() else {
+            return Err(ThemeStoreError::Http(404));
+        };
+        let resp = self
+            .client
+            .get(format!("{}{}", self.base_url, path))
+            .send()
+            .await
+            .map_err(|e| ThemeStoreError::Network(e.to_string()))?;
+        if !resp.status().is_success() {
+            return Err(ThemeStoreError::Http(resp.status().as_u16()));
+        }
+        let bytes = resp
+            .bytes()
+            .await
+            .map_err(|e| ThemeStoreError::Network(e.to_string()))?;
+        if bytes.len() as u64 > MAX_PREVIEW_BYTES {
+            return Err(ThemeStoreError::Oversized {
+                expected: MAX_PREVIEW_BYTES,
+                got: bytes.len() as u64,
+            });
+        }
+        Ok(bytes.to_vec())
+    }
 }
 
 /// Checks downloaded `bytes` against the catalog `entry`'s declared

solitaire_data/src/transfer.rs

@@ -0,0 +1,137 @@
+//! Local data export/import (Phase M — sync transparency).
+//!
+//! Bundles every player-owned JSON save (settings, stats, achievements,
+//! progress) into one versioned backup file so a player can move their
+//! data between devices without an account, or keep a manual backup.
+//!
+//! The bundle deliberately excludes the in-progress game and the replay
+//! history: the former is transient, the latter can be large and is
+//! shareable through the replay upload path instead.
+
+use std::fs;
+use std::io;
+use std::path::{Path, PathBuf};
+
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+
+use crate::settings::Settings;
+use solitaire_sync::{AchievementRecord, PlayerProgress, StatsSnapshot};
+
+/// Bundle format version. Bump on any breaking shape change; the loader
+/// rejects newer versions rather than misreading them.
+pub const DATA_BUNDLE_SCHEMA_VERSION: u32 = 1;
+
+/// File name of the default backup location (next to the other saves).
+pub const DATA_BUNDLE_FILE_NAME: &str = "ferrous-solitaire-backup.json";
+
+/// One-file backup of every player-owned JSON save.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct DataBundle {
+    /// Format version — see [`DATA_BUNDLE_SCHEMA_VERSION`].
+    pub schema_version: u32,
+    /// When the bundle was written.
+    pub exported_at: DateTime<Utc>,
+    pub settings: Settings,
+    pub stats: StatsSnapshot,
+    pub achievements: Vec<AchievementRecord>,
+    pub progress: PlayerProgress,
+}
+
+/// Why a bundle could not be loaded.
+#[derive(Debug, thiserror::Error)]
+pub enum BundleError {
+    #[error("could not read backup file: {0}")]
+    Io(#[from] io::Error),
+    #[error("backup file is not valid JSON: {0}")]
+    Parse(#[from] serde_json::Error),
+    #[error("backup was written by a newer app version (schema {found} > {supported})")]
+    UnsupportedVersion { found: u32, supported: u32 },
+}
+
+/// Default backup path: `<data dir>/<app dir>/ferrous-solitaire-backup.json`,
+/// or `None` when no data directory is available on this platform.
+pub fn data_bundle_path() -> Option<PathBuf> {
+    crate::data_dir().map(|d| d.join(crate::APP_DIR_NAME).join(DATA_BUNDLE_FILE_NAME))
+}
+
+/// Write `bundle` to `path` atomically (`.tmp` → rename), creating parent
+/// directories as needed. Mirrors the other save-file writers.
+pub fn save_bundle_to(path: &Path, bundle: &DataBundle) -> io::Result<()> {
+    if let Some(parent) = path.parent() {
+        fs::create_dir_all(parent)?;
+    }
+    let json = serde_json::to_string_pretty(bundle).map_err(io::Error::other)?;
+    let tmp = path.with_extension("json.tmp");
+    fs::write(&tmp, json.as_bytes())?;
+    fs::rename(&tmp, path)?;
+    Ok(())
+}
+
+/// Read and validate a bundle from `path`. Unlike the per-file loaders this
+/// does NOT default-on-error — an import silently replacing player data
+/// with defaults would be destructive, so every failure is surfaced.
+pub fn load_bundle_from(path: &Path) -> Result<DataBundle, BundleError> {
+    let data = fs::read(path)?;
+    let bundle: DataBundle = serde_json::from_slice(&data)?;
+    if bundle.schema_version > DATA_BUNDLE_SCHEMA_VERSION {
+        return Err(BundleError::UnsupportedVersion {
+            found: bundle.schema_version,
+            supported: DATA_BUNDLE_SCHEMA_VERSION,
+        });
+    }
+    Ok(bundle)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn sample_bundle() -> DataBundle {
+        DataBundle {
+            schema_version: DATA_BUNDLE_SCHEMA_VERSION,
+            exported_at: Utc::now(),
+            settings: Settings::default(),
+            stats: StatsSnapshot {
+                games_played: 7,
+                ..Default::default()
+            },
+            achievements: vec![],
+            progress: PlayerProgress::default(),
+        }
+    }
+
+    #[test]
+    fn round_trips_through_disk() {
+        let dir = std::env::temp_dir().join(format!("bundle_test_{}", std::process::id()));
+        let path = dir.join(DATA_BUNDLE_FILE_NAME);
+        let bundle = sample_bundle();
+        save_bundle_to(&path, &bundle).expect("save should succeed");
+        let loaded = load_bundle_from(&path).expect("load should succeed");
+        assert_eq!(loaded.schema_version, DATA_BUNDLE_SCHEMA_VERSION);
+        assert_eq!(loaded.stats.games_played, 7);
+        let _ = fs::remove_dir_all(&dir);
+    }
+
+    #[test]
+    fn rejects_newer_schema() {
+        let dir = std::env::temp_dir().join(format!("bundle_test_v_{}", std::process::id()));
+        let path = dir.join(DATA_BUNDLE_FILE_NAME);
+        let mut bundle = sample_bundle();
+        bundle.schema_version = DATA_BUNDLE_SCHEMA_VERSION + 1;
+        save_bundle_to(&path, &bundle).expect("save should succeed");
+        assert!(matches!(
+            load_bundle_from(&path),
+            Err(BundleError::UnsupportedVersion { .. })
+        ));
+        let _ = fs::remove_dir_all(&dir);
+    }
+
+    #[test]
+    fn missing_file_is_an_io_error() {
+        assert!(matches!(
+            load_bundle_from(Path::new("/nonexistent/backup.json")),
+            Err(BundleError::Io(_))
+        ));
+    }
+}

solitaire_engine/src/achievement_plugin.rs

@@ -67,6 +67,16 @@ pub struct AchievementsResource(pub Vec<AchievementRecord>);
 #[derive(Resource, Debug, Clone)]
 pub struct AchievementsStoragePath(pub Option<PathBuf>);
 
+/// Set wrapping the win-path achievement evaluator. It writes
+/// `AchievementsResource`/`ProgressResource` and emits unlock events; UI
+/// readers of those (HUD popovers, the stats/achievements panels) order
+/// themselves `.after(AchievementEval)`. The replay-completion evaluator is
+/// deliberately NOT a member: it runs after `AutoComplete`, and panel chains
+/// that need `.after(AchievementEval)` run before `AutoComplete` — putting
+/// both in one set would close an ordering cycle (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AchievementEval;
+
 pub struct AchievementPlugin {
     pub storage_path: Option<PathBuf>,
 }
@@ -119,9 +129,13 @@ impl Plugin for AchievementPlugin {
             .add_systems(
                 Update,
                 evaluate_on_win
+                    .in_set(AchievementEval)
                     .after(GameMutation)
                     .after(StatsUpdate)
-                    .after(ProgressUpdate),
+                    .after(ProgressUpdate)
+                    // The unlock/XP/level-up events it emits are drained by
+                    // the toast pipeline this frame (#143).
+                    .before(crate::animation_plugin::AnimFx),
             )
             // Achievement-onboarding cue: fires once after the player's very
             // first win to teach the Achievements panel exists. Must run
@@ -131,20 +145,50 @@ impl Plugin for AchievementPlugin {
                 Update,
                 fire_achievement_onboarding_toast
                     .after(GameMutation)
-                    .after(StatsUpdate),
+                    .after(StatsUpdate)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters)
+                    // Writes the one-shot onboarding flag into
+                    // SettingsResource: board painters re-read settings, so
+                    // land the write first; UiTextFx members read disjoint
+                    // settings fields (reduce-motion), so writer/reader
+                    // order there is provably irrelevant (#143).
+                    .before(crate::card_plugin::BoardVisuals)
+                    .ambiguous_with(crate::ui_theme::UiTextFx)
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             )
             // Open/close/tab handling moved to `you_hub_plugin`
             // (Phase E) — this plugin now owns body content + scroll.
-            .add_systems(Update, scroll_achievements_panel)
             .add_systems(
                 Update,
-                crate::ui_modal::touch_scroll_panel::<AchievementsScrollable>,
+                scroll_achievements_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            )
+            .add_systems(
+                Update,
+                crate::ui_modal::touch_scroll_panel::<AchievementsScrollable>
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
             )
             // Event-driven unlock: observe `ReplayPlaybackState` and unlock
             // `cinephile` the first time playback runs to natural completion.
             // Reads the resource via `Option<Res<_>>` so headless tests that
             // omit `ReplayPlaybackPlugin` still build.
-            .add_systems(Update, evaluate_cinephile_on_replay_completion);
+            .add_systems(
+                Update,
+                // Shares the unlock stream and AchievementsResource with
+                // evaluate_on_win; ordered after it and before the toast
+                // pipeline that drains the unlock events (#143).
+                evaluate_cinephile_on_replay_completion
+                    .after(evaluate_on_win)
+                    // The stats overlay's watch-replay button (ordered
+                    // before AutoComplete) writes ReplayPlaybackState this
+                    // system reads.
+                    .after(crate::auto_complete_plugin::AutoComplete)
+                    .before(crate::animation_plugin::AnimFx),
+            );
     }
 }
 

solitaire_engine/src/animation_plugin.rs

@@ -179,10 +179,13 @@ pub struct ToastStackRoot;
 pub struct ToastNode;
 
 /// Logical-pixel gap between the screen bottom and the toast stack,
-/// before safe-area insets. Clears the Phase F bottom action bar on
-/// touch (compact 44px buttons + primary 64px trio + bar padding);
-/// desktop's shorter bar needs less.
-const TOAST_STACK_BASE_BOTTOM_PX: f32 = if USE_TOUCH_UI_LAYOUT { 112.0 } else { 72.0 };
+/// before safe-area insets. Clears the floating glass tab bar on touch
+/// (its margin + height + breathing room); desktop's docked bar needs less.
+const TOAST_STACK_BASE_BOTTOM_PX: f32 = if USE_TOUCH_UI_LAYOUT {
+    crate::hud_plugin::tab_bar::TAB_BAR_CLEARANCE_PX
+} else {
+    72.0
+};
 
 /// Spawns the persistent [`ToastStackRoot`] container at startup.
 fn spawn_toast_stack_root(mut commands: Commands) {
@@ -227,6 +230,14 @@ fn adopt_toasts_into_stack(
 /// Drives all linear card animations (`CardAnim`), toast notifications, deal stagger, win cascade, and the auto-complete card-slide sequence.
 pub struct AnimationPlugin;
 
+/// Set wrapping this plugin's Update chain (card slide/cascade animation and
+/// the toast pipeline). Ordered after [`crate::card_animation::CardTweenFx`]
+/// on the shared visual spine — members write card `Transform`s, which every
+/// other painter set also touches — and after the toast/stat/progress writer
+/// sets so the toast handlers drain this frame's events (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnimFx;
+
 impl Plugin for AnimationPlugin {
     fn build(&self, app: &mut App) {
         // Register the events this plugin consumes so tests that don't include
@@ -250,12 +261,36 @@ impl Plugin for AnimationPlugin {
             .init_resource::<ToastQueue>()
             .init_resource::<ActiveToast>()
             .add_systems(Startup, (init_slide_duration, spawn_toast_stack_root))
+            .configure_sets(
+                Update,
+                AnimFx
+                    // Visual spine: …BoardVisuals < MarkerVisuals <
+                    // CardTweenFx < AnimFx < FeedbackFx (#143). GameMutation
+                    // ordering is inherited transitively.
+                    .after(crate::card_animation::CardTweenFx)
+                    .after(crate::table_plugin::MarkerVisuals)
+                    // Stats/progress must settle before the win/level-up
+                    // toast handlers read their events. (No edge against
+                    // InfoToastWriters: toast writers exist on both sides
+                    // of this set — enqueue_toasts drains via cursor and
+                    // joins the club instead; a toast surfacing one frame
+                    // later is invisible.)
+                    .after(crate::stats_plugin::StatsUpdate)
+                    .after(crate::progress_plugin::ProgressUpdate)
+                    .after(GameMutation)
+                    // HUD text pulses are disjoint from the card entities
+                    // this set animates (see UiTextFx × BoardVisuals, #143).
+                    .ambiguous_with(crate::ui_theme::UiTextFx),
+            )
             .add_systems(
                 Update,
                 (
                     advance_card_anims,
-                    sync_slide_duration,
-                    handle_win_cascade,
+                    // Both drain SettingsChangedEvent / read anim-speed
+                    // fields via cursor; a home deal-option edit surfacing
+                    // one frame later is invisible (#143).
+                    sync_slide_duration.ambiguous_with(crate::settings_plugin::SettingsAccess),
+                    handle_win_cascade.ambiguous_with(crate::settings_plugin::SettingsAccess),
                     handle_achievement_toast,
                     handle_levelup_toast,
                     handle_daily_goal_announcement_toast,
@@ -263,16 +298,23 @@ impl Plugin for AnimationPlugin {
                     handle_weekly_toast,
                     handle_time_attack_toast,
                     handle_challenge_toast,
-                    handle_settings_toast,
+                    handle_settings_toast.ambiguous_with(crate::settings_plugin::SettingsAccess),
                     handle_auto_complete_toast,
                     handle_xp_awarded_toast,
                     handle_move_rejected_toast,
                     handle_warning_toast,
                     tick_toasts,
-                    (enqueue_toasts, drive_toast_display).chain(),
+                    (
+                        enqueue_toasts
+                            .in_set(crate::game_plugin::InfoToastWriters)
+                            .ambiguous_with(crate::game_plugin::InfoToastWriters),
+                        drive_toast_display,
+                    )
+                        .chain(),
                     adopt_toasts_into_stack,
                 )
-                    .after(GameMutation),
+                    .chain()
+                    .in_set(AnimFx),
             );
     }
 }

solitaire_engine/src/assets/hud_icon_svg.rs

@@ -0,0 +1,127 @@
+//! SVG builders for the floating tab bar's action icons.
+//!
+//! The touch tab bar (`hud_plugin::tab_bar`) is icon-first, but the bundled
+//! FiraMono face has no icon glyphs (and the Geometric Shapes block U+25xx
+//! is missing on Android entirely), so the icons are authored here as tiny
+//! stroke-based SVGs and rasterised through the same `usvg`/`resvg` pipeline
+//! as the card themes (`assets::rasterize_svg`).
+//!
+//! Icons are drawn in **white** on a transparent background inside a
+//! 24-unit logical box; the spawn site tints them to the theme colour via
+//! `ImageNode::color` (a per-node multiply), so one texture serves every
+//! button state.
+
+use bevy::image::Image;
+use bevy::math::UVec2;
+
+use super::svg_loader::{SvgLoaderError, rasterize_svg};
+
+/// Rasterisation size for one tab-bar icon texture. Icons display at
+/// 24 logical px; 96 px texels keep them crisp at the Fold's 1.2 scale
+/// factor (and any future 3× phone) while staying trivially small.
+pub const HUD_ICON_TEXTURE_PX: u32 = 96;
+
+/// The five actions the floating touch tab bar can show.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum HudIcon {
+    /// Counter-clockwise "take back" arrow.
+    Undo,
+    /// Two offset card outlines — draw from the stock.
+    Draw,
+    /// Lightbulb — highlight a suggested move.
+    Hint,
+    /// Two vertical bars.
+    Pause,
+    /// Three-line hamburger — the floating menu button.
+    Menu,
+}
+
+impl HudIcon {
+    /// Build the icon's SVG document. All icons share one visual language:
+    /// 2-unit white strokes, round caps, transparent fill, 24-unit box.
+    pub fn svg(self) -> String {
+        let body = match self {
+            // Arrow head pointing left into a half-circle sweeping back
+            // over the top — the conventional undo mark.
+            HudIcon::Undo => concat!(
+                r##"<path d="M 8 5 L 4 9 L 8 13"/>"##,
+                r##"<path d="M 4 9 H 14 A 5.5 5.5 0 0 1 14 20 H 8"/>"##,
+            ),
+            // Back card peeks out behind the front card; the front card is
+            // drawn second so its stroke reads on top.
+            HudIcon::Draw => concat!(
+                r##"<rect x="8.5" y="3" width="11" height="15" rx="2"/>"##,
+                r##"<rect x="4" y="6.5" width="11" height="15" rx="2"/>"##,
+            ),
+            // Bulb dome with a flat lamp base beneath.
+            HudIcon::Hint => concat!(
+                r##"<path d="M 9 15.5 A 6.5 6.5 0 1 1 15 15.5 V 18 H 9 Z"/>"##,
+                r##"<path d="M 10 21 H 14"/>"##,
+            ),
+            HudIcon::Pause => concat!(
+                r##"<path d="M 9 6 V 18"/>"##,
+                r##"<path d="M 15 6 V 18"/>"##,
+            ),
+            HudIcon::Menu => concat!(
+                r##"<path d="M 4 6.5 H 20"/>"##,
+                r##"<path d="M 4 12 H 20"/>"##,
+                r##"<path d="M 4 17.5 H 20"/>"##,
+            ),
+        };
+        format!(
+            concat!(
+                r##"<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">"##,
+                r##"<g fill="none" stroke="#ffffff" stroke-width="2" "##,
+                r##"stroke-linecap="round" stroke-linejoin="round">{body}</g>"##,
+                r##"</svg>"##,
+            ),
+            body = body
+        )
+    }
+
+    /// Rasterise this icon into a Bevy [`Image`] at
+    /// [`HUD_ICON_TEXTURE_PX`] square.
+    pub fn rasterize(self) -> Result<Image, SvgLoaderError> {
+        rasterize_svg(self.svg().as_bytes(), UVec2::splat(HUD_ICON_TEXTURE_PX))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const ALL: [HudIcon; 5] = [
+        HudIcon::Undo,
+        HudIcon::Draw,
+        HudIcon::Hint,
+        HudIcon::Pause,
+        HudIcon::Menu,
+    ];
+
+    /// Every icon must survive the real usvg/resvg pipeline at the real
+    /// texture size — a malformed path here would otherwise only surface
+    /// as a blank button on device.
+    #[test]
+    fn every_icon_rasterizes_at_texture_size() {
+        for icon in ALL {
+            let img = icon.rasterize().expect("icon SVG must rasterise");
+            assert_eq!(img.width(), HUD_ICON_TEXTURE_PX, "{icon:?} width");
+            assert_eq!(img.height(), HUD_ICON_TEXTURE_PX, "{icon:?} height");
+        }
+    }
+
+    /// Rasterised icons must contain visible (non-transparent) pixels —
+    /// guards against a stroke accidentally drawn outside the viewBox.
+    #[test]
+    fn every_icon_has_visible_pixels() {
+        for icon in ALL {
+            let img = icon.rasterize().expect("icon SVG must rasterise");
+            let data = img.data.as_ref().expect("rasterised image has data");
+            let opaque = data.chunks_exact(4).filter(|px| px[3] > 0).count();
+            assert!(
+                opaque > 100,
+                "{icon:?} renders only {opaque} visible pixels"
+            );
+        }
+    }
+}

solitaire_engine/src/assets/mod.rs

@@ -5,6 +5,7 @@
 //! custom `AssetSource` implementations used by the theme system.
 
 pub mod card_face_svg;
+pub mod hud_icon_svg;
 pub mod icon_svg;
 pub mod sources;
 pub mod svg_loader;

solitaire_engine/src/card_animation/mod.rs

@@ -83,6 +83,14 @@ use tuning::update_input_platform;
 /// long as no single entity carries both `CardAnim` and `CardAnimation`.
 pub struct CardAnimationPlugin;
 
+/// Set wrapping this plugin's Update chain (curve tweens, hover/drag
+/// visuals). First anim stage on the visual spine: …BoardVisuals <
+/// MarkerVisuals < CardTweenFx < [`crate::animation_plugin::AnimFx`] <
+/// FeedbackFx — members write card `Transform`s, which every other painter
+/// set also touches (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct CardTweenFx;
+
 impl Plugin for CardAnimationPlugin {
     fn build(&self, app: &mut App) {
         // Register events and resources idempotently — double-registration is
@@ -115,7 +123,14 @@ impl Plugin for CardAnimationPlugin {
                     // still present in the same frame it was removed (deferred
                     // commands aren't applied until the next ApplyDeferred
                     // point), causing a 1-frame gap between every chain step.
-                    ApplyDeferred,
+                    //
+                    // `ambiguous_with_all`: an explicit sync point conflicts
+                    // (on `World`) with every unordered system in the
+                    // schedule. Only the flush of THIS chain's commands needs
+                    // ordering — the chain edges provide that; whether an
+                    // unrelated system's commands flush here or at the next
+                    // sync point is immaterial to it (#143).
+                    ApplyDeferred.ambiguous_with_all(),
                     // After each animation finishes, pop the next chain segment.
                     advance_animation_chains,
                     // Interaction visuals (run after animation for final positions).
@@ -123,10 +138,24 @@ impl Plugin for CardAnimationPlugin {
                     apply_hover_scale,
                     apply_drag_visual,
                     // Drain buffered inputs only when no animations remain.
-                    drain_input_buffer,
+                    // It re-emits buffered undo/new-game requests, so it
+                    // joins the self-ambiguous writer clubs (#143).
+                    drain_input_buffer
+                        .in_set(crate::game_plugin::UndoRequestWriters)
+                        .ambiguous_with(crate::game_plugin::UndoRequestWriters),
                 )
                     .chain()
-                    .after(GameMutation),
+                    .in_set(CardTweenFx),
+            )
+            .configure_sets(
+                Update,
+                CardTweenFx
+                    .after(GameMutation)
+                    .after(crate::table_plugin::MarkerVisuals)
+                    // HUD text pulses touch Transform on UI entities only —
+                    // disjoint from the card entities this set animates
+                    // (same rationale as UiTextFx × BoardVisuals, #143).
+                    .ambiguous_with(crate::ui_theme::UiTextFx),
             );
     }
 }

solitaire_engine/src/card_plugin/mod.rs

@@ -592,7 +592,9 @@ impl Plugin for CardPlugin {
                     tick_right_click_highlights,
                     clear_right_click_highlights_on_state_change,
                     clear_right_click_highlights_on_pause,
-                    tick_hint_highlight,
+                    // Reads only the anim-speed/reduce-motion flags; a frame
+                    // of lag is invisible (#143).
+                    tick_hint_highlight.ambiguous_with(crate::settings_plugin::SettingsAccess),
                     update_stock_empty_indicator,
                     update_stock_count_badge.run_if(resource_changed::<GameStateResource>),
                     collect_resize_events,

solitaire_engine/src/challenge_plugin.rs

@@ -11,8 +11,7 @@ use solitaire_data::{challenge_count, challenge_seed_for, save_progress_to};
 use crate::events::{
     GameWonEvent, InfoToastEvent, NewGameRequestEvent, StartChallengeRequestEvent,
 };
-use crate::game_plugin::GameMutation;
-use crate::progress_plugin::{ProgressResource, ProgressStoragePath, ProgressUpdate};
+use crate::progress_plugin::{ProgressResource, ProgressStoragePath};
 use crate::resources::GameStateResource;
 
 /// Minimum player level required to start a Challenge run.
@@ -38,8 +37,28 @@ impl Plugin for ChallengePlugin {
             .add_message::<StartChallengeRequestEvent>()
             .add_message::<InfoToastEvent>()
             // Run after ProgressUpdate so we don't fight ProgressPlugin's add_xp.
-            .add_systems(Update, advance_on_challenge_win.after(ProgressUpdate))
-            .add_systems(Update, handle_start_challenge_request.before(GameMutation));
+            // Ordering comes from the mode-completion chain configured in
+            // progress_plugin; the toast it emits joins the writer club
+            // drained by the toast pipeline this frame (#143).
+            .add_systems(
+                Update,
+                advance_on_challenge_win
+                    .in_set(crate::progress_plugin::ChallengeCompletion)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            )
+            // ModeStart places it between the stats abandon-recorder and
+            // GameMutation; it shares the new-game request/toast streams
+            // with the other writers (#143).
+            .add_systems(
+                Update,
+                handle_start_challenge_request
+                    .in_set(crate::game_plugin::ModeStart)
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            );
     }
 }
 

solitaire_engine/src/cheat_sheet_plugin.rs

@@ -0,0 +1,194 @@
+//! Hold-`/` hotkey cheat sheet (Phase J).
+//!
+//! While `/` is held on a keyboard platform, a lightweight overlay
+//! lists every binding from [`crate::hotkeys::HOTKEYS`] — the same
+//! table the onboarding slide teaches from, so the two can never
+//! disagree. Releasing the key hides it instantly; it never captures
+//! input, never pauses the game, and never spawns while a modal owns
+//! the screen (which also keeps it out of the seed-entry text field's
+//! way).
+//!
+//! Not a `spawn_modal` modal on purpose: modals are sticky and guarded;
+//! this is a momentary reference card, closer to a tooltip than a
+//! dialog.
+
+use bevy::input::ButtonInput;
+use bevy::prelude::*;
+
+use crate::font_plugin::FontResource;
+use crate::hotkeys::HOTKEYS;
+use crate::platform::SHOW_KEYBOARD_ACCELERATORS;
+use crate::ui_modal::ModalScrim;
+use crate::ui_theme::{
+    ACCENT_PRIMARY, BG_ELEVATED, BORDER_STRONG, HighContrastBorder, RADIUS_MD, TEXT_PRIMARY,
+    TEXT_SECONDARY, TYPE_BODY, TYPE_CAPTION, VAL_SPACE_1, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4,
+    Z_TOOLTIP,
+};
+
+/// Marker on the cheat-sheet overlay root.
+#[derive(Component, Debug)]
+pub struct CheatSheetOverlay;
+
+/// Registers the hold-`/` driver. Inert on touch-first builds.
+pub struct CheatSheetPlugin;
+
+impl Plugin for CheatSheetPlugin {
+    fn build(&self, app: &mut App) {
+        app.init_resource::<ButtonInput<KeyCode>>()
+            .add_systems(Update, drive_cheat_sheet);
+    }
+}
+
+/// Shows the overlay while `/` is held (and no modal owns the screen);
+/// hides it the frame the key releases.
+fn drive_cheat_sheet(
+    keys: Res<ButtonInput<KeyCode>>,
+    scrims: Query<(), With<ModalScrim>>,
+    existing: Query<Entity, With<CheatSheetOverlay>>,
+    font_res: Option<Res<FontResource>>,
+    mut commands: Commands,
+) {
+    if !SHOW_KEYBOARD_ACCELERATORS {
+        return;
+    }
+    let held = keys.pressed(KeyCode::Slash);
+    if held && existing.is_empty() && scrims.is_empty() {
+        spawn_cheat_sheet(&mut commands, font_res.as_deref());
+    } else if !held {
+        for entity in &existing {
+            commands.entity(entity).despawn();
+        }
+    }
+}
+
+fn spawn_cheat_sheet(commands: &mut Commands, font_res: Option<&FontResource>) {
+    let font_handle = font_res.map(|f| f.0.clone()).unwrap_or_default();
+    let font_header = TextFont {
+        font: font_handle.clone(),
+        font_size: TYPE_BODY,
+        ..default()
+    };
+    let font_keys = TextFont {
+        font: font_handle.clone(),
+        font_size: TYPE_CAPTION,
+        ..default()
+    };
+    let font_desc = TextFont {
+        font: font_handle,
+        font_size: TYPE_CAPTION,
+        ..default()
+    };
+
+    commands
+        .spawn((
+            CheatSheetOverlay,
+            Node {
+                position_type: PositionType::Absolute,
+                right: Val::Px(16.0),
+                top: Val::Percent(8.0),
+                flex_direction: FlexDirection::Column,
+                row_gap: VAL_SPACE_1,
+                padding: UiRect::all(VAL_SPACE_4),
+                border: UiRect::all(Val::Px(1.0)),
+                border_radius: BorderRadius::all(Val::Px(RADIUS_MD)),
+                max_height: Val::Percent(84.0),
+                overflow: Overflow::scroll_y(),
+                ..default()
+            },
+            BackgroundColor(BG_ELEVATED),
+            BorderColor::all(BORDER_STRONG),
+            HighContrastBorder::with_default(BORDER_STRONG),
+            GlobalZIndex(Z_TOOLTIP),
+        ))
+        .with_children(|panel| {
+            panel.spawn((
+                Text::new("Keyboard shortcuts"),
+                font_header.clone(),
+                TextColor(TEXT_PRIMARY),
+                Node {
+                    margin: UiRect::bottom(VAL_SPACE_2),
+                    ..default()
+                },
+            ));
+            for row in HOTKEYS {
+                panel
+                    .spawn(Node {
+                        flex_direction: FlexDirection::Row,
+                        column_gap: VAL_SPACE_3,
+                        ..default()
+                    })
+                    .with_children(|line| {
+                        line.spawn((
+                            Text::new(row.keys),
+                            font_keys.clone(),
+                            TextColor(ACCENT_PRIMARY),
+                            Node {
+                                min_width: Val::Px(110.0),
+                                ..default()
+                            },
+                        ));
+                        line.spawn((
+                            Text::new(row.description),
+                            font_desc.clone(),
+                            TextColor(TEXT_SECONDARY),
+                        ));
+                    });
+            }
+        });
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn app() -> App {
+        let mut app = App::new();
+        app.add_plugins(MinimalPlugins)
+            .add_plugins(CheatSheetPlugin);
+        app.update();
+        app
+    }
+
+    fn overlay_count(app: &mut App) -> usize {
+        app.world_mut()
+            .query::<&CheatSheetOverlay>()
+            .iter(app.world())
+            .count()
+    }
+
+    #[test]
+    fn holding_slash_shows_and_release_hides() {
+        let mut app = app();
+        app.world_mut()
+            .resource_mut::<ButtonInput<KeyCode>>()
+            .press(KeyCode::Slash);
+        app.update();
+        assert_eq!(overlay_count(&mut app), 1, "held / must show the sheet");
+        // Still held on later frames: exactly one overlay, no stacking.
+        app.update();
+        assert_eq!(overlay_count(&mut app), 1);
+
+        app.world_mut()
+            .resource_mut::<ButtonInput<KeyCode>>()
+            .release(KeyCode::Slash);
+        app.update();
+        app.update();
+        assert_eq!(overlay_count(&mut app), 0, "release must hide the sheet");
+    }
+
+    #[test]
+    fn suppressed_while_a_modal_is_open() {
+        let mut app = app();
+        app.world_mut().spawn(ModalScrim);
+        app.update();
+        app.world_mut()
+            .resource_mut::<ButtonInput<KeyCode>>()
+            .press(KeyCode::Slash);
+        app.update();
+        assert_eq!(
+            overlay_count(&mut app),
+            0,
+            "the sheet must not spawn over a modal (or into a text field)"
+        );
+    }
+}

solitaire_engine/src/contextual_tips_plugin.rs

@@ -0,0 +1,309 @@
+//! Contextual one-time tips (Phase I of the 2026-07 UI redesign).
+//!
+//! Everything the first-run onboarding doesn't cover is invisible until
+//! stumbled upon: hint cycling, the radial quick-action menu. These
+//! tips fire **from the situation, not a tour** — each exactly once,
+//! recorded in `Settings` like `shown_achievement_onboarding`:
+//!
+//! - **Stall tip** — after [`STALL_TIP_SECS`] with no board change in an
+//!   active game, an info toast points at Hint. A player staring at a
+//!   stuck board is the one moment the tip is welcome.
+//! - **Radial tip** — once a game reaches [`RADIAL_TIP_MIN_MOVES`] moves
+//!   (an engaged player) and the radial menu has never been opened, an
+//!   info toast teaches the long-press / right-click gesture. Opening
+//!   the radial organically marks the tip as unnecessary — it is never
+//!   shown to someone who already knows.
+//!
+//! Tips render through the queued [`InfoToastEvent`] path, so they share
+//! the unified toast stack and never interrupt play.
+
+use bevy::prelude::*;
+
+use solitaire_data::save_settings_to;
+
+use crate::events::{InfoToastEvent, StateChangedEvent};
+use crate::game_plugin::GameMutation;
+use crate::pause_plugin::PausedResource;
+use crate::platform::SHOW_KEYBOARD_ACCELERATORS;
+use crate::radial_menu::RightClickRadialState;
+use crate::resources::GameStateResource;
+use crate::settings_plugin::{SettingsResource, SettingsStoragePath};
+use crate::ui_modal::ModalScrim;
+
+/// Seconds without any board change before the stall tip fires.
+/// Long enough that normal thinking never triggers it; short enough to
+/// reach a genuinely stuck player before they quit.
+const STALL_TIP_SECS: f32 = 45.0;
+
+/// Move count at which an engaged player earns the radial-menu teach.
+const RADIAL_TIP_MIN_MOVES: u32 = 15;
+
+/// Stall-tip copy per platform input vocabulary.
+const STALL_TIP: &str = if SHOW_KEYBOARD_ACCELERATORS {
+    "Stuck? Press H for a hint."
+} else {
+    "Stuck? Tap Hint in the bottom bar for a suggested move."
+};
+
+/// Radial-tip copy per platform input vocabulary.
+const RADIAL_TIP: &str = if SHOW_KEYBOARD_ACCELERATORS {
+    "Tip: right-click a card for quick actions."
+} else {
+    "Tip: long-press a card for quick actions."
+};
+
+/// Seconds of board inactivity, frozen while paused / a modal is open,
+/// reset by every [`StateChangedEvent`].
+#[derive(Resource, Debug, Default)]
+pub struct StallClock(pub f32);
+
+/// Registers the stall clock and the two tip triggers.
+pub struct ContextualTipsPlugin;
+
+impl Plugin for ContextualTipsPlugin {
+    fn build(&self, app: &mut App) {
+        app.init_resource::<StallClock>()
+            .add_message::<InfoToastEvent>()
+            .add_message::<StateChangedEvent>()
+            .add_systems(
+                Update,
+                (
+                    tick_stall_clock,
+                    fire_stall_hint_tip
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
+                    observe_radial_menu_use,
+                    fire_radial_menu_tip
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
+                )
+                    .chain()
+                    .after(GameMutation),
+            );
+    }
+}
+
+/// Advances the stall clock; resets on any board change; freezes while
+/// paused, while a modal owns the screen, or when the game is over.
+fn tick_stall_clock(
+    time: Res<Time>,
+    mut state_events: MessageReader<StateChangedEvent>,
+    paused: Option<Res<PausedResource>>,
+    scrims: Query<(), With<ModalScrim>>,
+    game: Option<Res<GameStateResource>>,
+    mut clock: ResMut<StallClock>,
+) {
+    if state_events.read().next().is_some() {
+        clock.0 = 0.0;
+        return;
+    }
+    if paused.is_some_and(|p| p.0)
+        || !scrims.is_empty()
+        || game.as_ref().is_none_or(|g| g.0.is_won())
+    {
+        // Frozen, not reset: backgrounding into a menu mid-stall
+        // shouldn't restart the wait.
+        return;
+    }
+    clock.0 += time.delta_secs();
+}
+
+/// Fires the one-shot stall tip once the clock passes the threshold in
+/// a game the player has actually started (at least one move).
+fn fire_stall_hint_tip(
+    clock: Res<StallClock>,
+    game: Option<Res<GameStateResource>>,
+    mut settings: Option<ResMut<SettingsResource>>,
+    storage_path: Option<Res<SettingsStoragePath>>,
+    mut toast: MessageWriter<InfoToastEvent>,
+) {
+    let Some(s) = settings.as_mut() else { return };
+    if s.0.shown_stall_hint_tip || clock.0 < STALL_TIP_SECS {
+        return;
+    }
+    if game
+        .as_ref()
+        .is_none_or(|g| g.0.move_count() == 0 || g.0.is_won())
+    {
+        return;
+    }
+    toast.write(InfoToastEvent(STALL_TIP.to_string()));
+    s.0.shown_stall_hint_tip = true;
+    persist(storage_path.as_deref(), &s.0);
+}
+
+/// A player who opens the radial menu on their own doesn't need the
+/// teach — mark the tip done silently.
+fn observe_radial_menu_use(
+    radial: Option<Res<RightClickRadialState>>,
+    mut settings: Option<ResMut<SettingsResource>>,
+    storage_path: Option<Res<SettingsStoragePath>>,
+) {
+    let Some(radial) = radial else { return };
+    if !radial.is_active() {
+        return;
+    }
+    let Some(s) = settings.as_mut() else { return };
+    if s.0.shown_radial_menu_tip {
+        return;
+    }
+    s.0.shown_radial_menu_tip = true;
+    persist(storage_path.as_deref(), &s.0);
+}
+
+/// Fires the one-shot radial teach for an engaged player who has never
+/// opened the menu themselves.
+fn fire_radial_menu_tip(
+    game: Option<Res<GameStateResource>>,
+    mut settings: Option<ResMut<SettingsResource>>,
+    storage_path: Option<Res<SettingsStoragePath>>,
+    mut toast: MessageWriter<InfoToastEvent>,
+) {
+    let Some(s) = settings.as_mut() else { return };
+    if s.0.shown_radial_menu_tip {
+        return;
+    }
+    if game
+        .as_ref()
+        .is_none_or(|g| g.0.move_count() < RADIAL_TIP_MIN_MOVES || g.0.is_won())
+    {
+        return;
+    }
+    toast.write(InfoToastEvent(RADIAL_TIP.to_string()));
+    s.0.shown_radial_menu_tip = true;
+    persist(storage_path.as_deref(), &s.0);
+}
+
+fn persist(storage_path: Option<&SettingsStoragePath>, settings: &solitaire_data::Settings) {
+    if let Some(p) = storage_path
+        && let Some(path) = p.0.as_deref()
+        && let Err(e) = save_settings_to(path, settings)
+    {
+        warn!("contextual tips: failed to persist tip flag: {e}");
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use bevy::ecs::message::Messages;
+    use solitaire_core::{DrawStockConfig, game_state::GameState};
+    use solitaire_data::Settings;
+
+    fn app_with(settings: Settings, game: GameState) -> App {
+        let mut app = App::new();
+        app.add_plugins(MinimalPlugins)
+            .add_plugins(ContextualTipsPlugin);
+        app.insert_resource(SettingsResource(settings));
+        app.insert_resource(GameStateResource(game));
+        app.update();
+        app
+    }
+
+    fn info_toast_count(app: &App) -> usize {
+        let events = app.world().resource::<Messages<InfoToastEvent>>();
+        let mut cursor = events.get_cursor();
+        cursor.read(events).count()
+    }
+
+    fn started_game() -> GameState {
+        let mut game = GameState::new(7, DrawStockConfig::DrawOne);
+        game.draw().expect("draw from fresh deal");
+        game
+    }
+
+    #[test]
+    fn stall_tip_fires_once_past_threshold() {
+        let mut app = app_with(Settings::default(), started_game());
+        app.world_mut().resource_mut::<StallClock>().0 = STALL_TIP_SECS + 1.0;
+        app.update();
+
+        assert_eq!(info_toast_count(&app), 1, "stall tip must fire");
+        assert!(
+            app.world()
+                .resource::<SettingsResource>()
+                .0
+                .shown_stall_hint_tip,
+            "the tip flag must set so it never repeats"
+        );
+
+        app.world_mut().resource_mut::<StallClock>().0 = STALL_TIP_SECS + 30.0;
+        app.world_mut()
+            .resource_mut::<Messages<InfoToastEvent>>()
+            .clear();
+        app.update();
+        assert_eq!(info_toast_count(&app), 0, "the tip is one-shot");
+    }
+
+    #[test]
+    fn stall_tip_needs_a_started_unwon_game() {
+        // Untouched deal: staring at the launch screen is not a stall.
+        let mut app = app_with(
+            Settings::default(),
+            GameState::new(7, DrawStockConfig::DrawOne),
+        );
+        app.world_mut().resource_mut::<StallClock>().0 = STALL_TIP_SECS + 1.0;
+        app.update();
+        assert_eq!(info_toast_count(&app), 0, "no tip on an untouched deal");
+
+        // Won game: nothing to hint at.
+        let mut won = started_game();
+        won.set_test_won(true);
+        let mut app = app_with(Settings::default(), won);
+        app.world_mut().resource_mut::<StallClock>().0 = STALL_TIP_SECS + 1.0;
+        app.update();
+        assert_eq!(info_toast_count(&app), 0, "no tip on a won game");
+    }
+
+    #[test]
+    fn stall_clock_resets_on_state_change() {
+        let mut app = app_with(Settings::default(), started_game());
+        app.world_mut().resource_mut::<StallClock>().0 = 30.0;
+        app.world_mut().write_message(StateChangedEvent);
+        app.update();
+        assert_eq!(
+            app.world().resource::<StallClock>().0,
+            0.0,
+            "any board change must reset the stall clock"
+        );
+    }
+
+    #[test]
+    fn radial_tip_fires_for_engaged_player() {
+        let mut game = started_game();
+        game.set_test_move_count(RADIAL_TIP_MIN_MOVES);
+        let mut app = app_with(Settings::default(), game);
+        app.update();
+
+        assert_eq!(
+            info_toast_count(&app),
+            1,
+            "radial tip must fire at the move threshold"
+        );
+        assert!(
+            app.world()
+                .resource::<SettingsResource>()
+                .0
+                .shown_radial_menu_tip
+        );
+    }
+
+    #[test]
+    fn radial_tip_suppressed_after_organic_use() {
+        let mut game = started_game();
+        game.set_test_move_count(RADIAL_TIP_MIN_MOVES);
+        let mut app = app_with(
+            Settings {
+                shown_radial_menu_tip: true,
+                ..Settings::default()
+            },
+            game,
+        );
+        app.update();
+        assert_eq!(
+            info_toast_count(&app),
+            0,
+            "a player who used the radial menu never sees the teach"
+        );
+    }
+}

solitaire_engine/src/core_game_plugin.rs

@@ -14,14 +14,14 @@ use crate::platform::{
 };
 use crate::{
     AchievementPlugin, AnimationPlugin, AssetSourcesPlugin, AutoCompletePlugin,
-    CardAnimationPlugin, CardPlugin, ChallengePlugin, CursorPlugin, DailyChallengePlugin,
-    DiagnosticsHudPlugin, DifficultyPlugin, FeedbackAnimPlugin, FontPlugin, GamePlugin, HelpPlugin,
-    HomePlugin, HudPlugin, InputPlugin, OnboardingPlugin, PausePlugin, PlayBySeedPlugin,
-    ProfilePlugin, ProgressPlugin, RadialMenuPlugin, ReplayOverlayPlugin, ReplayPlaybackPlugin,
-    SafeAreaInsetsPlugin, SelectionPlugin, SettingsPlugin, SolutionPlaybackPlugin, SplashPlugin,
-    StatsPlugin, SyncProvider, TablePlugin, ThemePlugin, ThemeRegistryPlugin, TimeAttackPlugin,
-    TouchSelectionPlugin, UiFocusPlugin, UiModalPlugin, UiTooltipPlugin, WeeklyGoalsPlugin,
-    WinSummaryPlugin,
+    CardAnimationPlugin, CardPlugin, ChallengePlugin, CheatSheetPlugin, ContextualTipsPlugin,
+    CursorPlugin, DailyChallengePlugin, DiagnosticsHudPlugin, DifficultyPlugin, FeedbackAnimPlugin,
+    FontPlugin, GamePlugin, HelpPlugin, HomePlugin, HudPlugin, InputPlugin, OnboardingPlugin,
+    PausePlugin, PlayBySeedPlugin, ProfilePlugin, ProgressPlugin, RadialMenuPlugin,
+    ReplayOverlayPlugin, ReplayPlaybackPlugin, SafeAreaInsetsPlugin, SelectionPlugin,
+    SettingsPlugin, SolutionPlaybackPlugin, SplashPlugin, StatsPlugin, SyncProvider, TablePlugin,
+    ThemePlugin, ThemeRegistryPlugin, TimeAttackPlugin, TouchSelectionPlugin, UiFocusPlugin,
+    UiModalPlugin, UiTooltipPlugin, WeeklyGoalsPlugin, WhatsNewPlugin, WinSummaryPlugin,
 };
 #[cfg(not(target_arch = "wasm32"))]
 use crate::{
@@ -115,6 +115,9 @@ impl Plugin for CoreGamePlugin {
             .add_plugins(PausePlugin)
             .add_plugins(SettingsPlugin::default())
             .add_plugins(OnboardingPlugin)
+            .add_plugins(WhatsNewPlugin)
+            .add_plugins(ContextualTipsPlugin)
+            .add_plugins(CheatSheetPlugin)
             .add_plugins(WinSummaryPlugin)
             .add_plugins(UiModalPlugin)
             .add_plugins(UiFocusPlugin)

solitaire_engine/src/cursor_plugin.rs

@@ -76,12 +76,31 @@ pub struct CursorPlugin;
 
 impl Plugin for CursorPlugin {
     fn build(&self, app: &mut App) {
+        // All three read the DragState/game state the input chain and
+        // mutation systems settle, so they run after both. The highlight
+        // painters write card/overlay Sprites and join the visual spine
+        // ahead of the board painters; the cursor icon touches only the
+        // window cursor (#143).
         app.add_systems(
             Update,
             (
-                update_cursor_icon,
+                update_cursor_icon
+                    .after(crate::input_plugin::PointerInput)
+                    .after(crate::game_plugin::GameMutation)
+                    .after(crate::selection_plugin::SelectionFx)
+                    .before(crate::card_plugin::BoardVisuals),
+                (
                     update_drop_highlights.run_if(resource_changed::<DragState>),
                     update_drop_target_overlays,
+                )
+                    .chain()
+                    .after(crate::input_plugin::PointerInput)
+                    .after(crate::game_plugin::GameMutation)
+                    // Selection maintenance clears DragState and the hint
+                    // poll writes highlight sprites — both settle first.
+                    .after(crate::selection_plugin::SelectionFx)
+                    .after(crate::pending_hint::PendingHint)
+                    .before(crate::card_plugin::BoardVisuals),
             ),
         );
     }

solitaire_engine/src/daily_challenge_plugin.rs

@@ -24,8 +24,8 @@ use crate::events::{
     GameWonEvent, InfoToastEvent, NewGameRequestEvent, StartDailyChallengeRequestEvent,
     WarningToastEvent, XpAwardedEvent,
 };
-use crate::game_plugin::GameMutation;
-use crate::progress_plugin::{ProgressResource, ProgressStoragePath, ProgressUpdate};
+
+use crate::progress_plugin::{ProgressResource, ProgressStoragePath};
 use crate::resources::GameStateResource;
 #[cfg(not(target_arch = "wasm32"))]
 use crate::sync_plugin::SyncProviderResource;
@@ -124,17 +124,51 @@ impl Plugin for DailyChallengePlugin {
             .add_message::<StartDailyChallengeRequestEvent>()
             .add_message::<WarningToastEvent>()
             .add_message::<XpAwardedEvent>()
-            // record/award after the base ProgressUpdate so we don't fight
-            // ProgressPlugin's add_xp on the same frame.
-            .add_systems(Update, handle_daily_completion.after(ProgressUpdate))
-            .add_systems(Update, handle_start_daily_request.before(GameMutation))
-            .add_systems(Update, check_daily_expiry_warning)
-            .add_systems(Update, check_date_rollover);
+            // Ordering comes from the mode-completion chain configured in
+            // progress_plugin; the toast it emits joins the writer club
+            // drained by the toast pipeline this frame (#143).
+            .add_systems(
+                Update,
+                handle_daily_completion
+                    .in_set(crate::progress_plugin::DailyCompletion)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            )
+            // ModeStart places it between the stats abandon-recorder and
+            // GameMutation; it shares the new-game request/toast streams
+            // with the other writers (#143).
+            .add_systems(
+                Update,
+                handle_start_daily_request
+                    .in_set(crate::game_plugin::ModeStart)
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            )
+            // One chain for the DailyChallengeResource writers/readers:
+            // the local date rollover replaces today's challenge and the
+            // expiry warning reads it. Before ModeStart so a rollover
+            // lands before the start handler reads the seed this frame
+            // (#143).
+            .add_systems(
+                Update,
+                (
+                    check_date_rollover,
+                    check_daily_expiry_warning
+                        .in_set(crate::game_plugin::WarningToastWriters)
+                        .ambiguous_with(crate::game_plugin::WarningToastWriters),
+                )
+                    .chain()
+                    .before(crate::game_plugin::ModeStart),
+            );
 
         // Server-challenge fetch uses SyncProviderResource (reqwest), not available on wasm.
+        // The poll replaces DailyChallengeResource, so it heads the same
+        // pre-ModeStart timeline as the rollover/expiry chain above (#143).
         #[cfg(not(target_arch = "wasm32"))]
         app.add_systems(Startup, fetch_server_challenge)
-            .add_systems(Update, poll_server_challenge);
+            .add_systems(Update, poll_server_challenge.before(check_date_rollover));
     }
 }
 

solitaire_engine/src/difficulty_plugin.rs

@@ -21,7 +21,6 @@ use solitaire_core::game_state::{DifficultyLevel, GameMode};
 use solitaire_data::difficulty_seeds::seeds_for;
 
 use crate::events::{NewGameRequestEvent, StartDifficultyRequestEvent};
-use crate::game_plugin::GameMutation;
 
 // ---------------------------------------------------------------------------
 // Resources
@@ -77,7 +76,16 @@ impl Plugin for DifficultyPlugin {
         app.init_resource::<DifficultyIndexResource>()
             .add_message::<StartDifficultyRequestEvent>()
             .add_message::<NewGameRequestEvent>()
-            .add_systems(Update, handle_difficulty_request.before(GameMutation));
+            // ModeStart places it between the stats abandon-recorder and
+            // GameMutation; it shares the new-game request stream with the
+            // other writers (#143).
+            .add_systems(
+                Update,
+                handle_difficulty_request
+                    .in_set(crate::game_plugin::ModeStart)
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
+            );
     }
 }
 

solitaire_engine/src/events.rs

@@ -151,6 +151,18 @@ pub struct SyncLogoutRequestEvent;
 #[derive(Message, Debug, Clone, Copy, Default)]
 pub struct DeleteAccountRequestEvent;
 
+/// Request to export every JSON save into one local backup bundle
+/// (Phase M — sync transparency). Fired by the Account tab's "Export
+/// data" button; handled in the `Last` schedule by `settings_plugin`.
+#[derive(Message, Debug, Clone, Copy, Default)]
+pub struct DataExportRequestEvent;
+
+/// Request to restore every JSON save from the local backup bundle
+/// (Phase M — sync transparency). Fired by the Account tab's "Import
+/// data" button; handled in the `Last` schedule by `settings_plugin`.
+#[derive(Message, Debug, Clone, Copy, Default)]
+pub struct DataImportRequestEvent;
+
 /// Request to toggle the pause overlay. Fired by the HUD "Pause" button so
 /// the same toggle path runs whether the player presses `Esc` or clicks.
 /// Consumed by `pause_plugin::toggle_pause`, which honours the same drag /

solitaire_engine/src/feedback_anim_plugin.rs

@@ -49,10 +49,11 @@ use solitaire_core::klondike_adapter::foundation_from_slot;
 use solitaire_data::AnimSpeed;
 
 use crate::animation_plugin::CardAnim;
-use crate::card_plugin::CardEntity;
+use crate::card_animation::{MotionCurve, sample_curve};
+use crate::card_plugin::{CardEntity, CardEntityIndex};
 use crate::events::{
-    DrawRequestEvent, FoundationCompletedEvent, MoveRejectedEvent, MoveRequestEvent,
-    NewGameRequestEvent,
+    DrawRequestEvent, FoundationCompletedEvent, HintVisualEvent, MoveRejectedEvent,
+    MoveRequestEvent, NewGameRequestEvent, StateChangedEvent,
 };
 use crate::game_plugin::GameMutation;
 use crate::layout::LayoutResource;
@@ -197,6 +198,22 @@ pub fn deal_stagger_jitter(card_id: u32) -> f32 {
 /// animation systems.
 pub struct FeedbackAnimPlugin;
 
+/// Set wrapping the shake/settle/deal/flourish systems. Last anim stage on
+/// the visual spine: …MarkerVisuals < CardTweenFx <
+/// [`crate::animation_plugin::AnimFx`] < FeedbackFx. Runs after
+/// MarkerVisuals because the foundation flourish tints pile-marker sprites,
+/// which the marker painters also write; the tint must win within the frame
+/// (#143). GameMutation ordering is inherited transitively.
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct FeedbackFx;
+
+/// Set wrapping the hint-ghost chain (spawn → tick → despawn). Ghost
+/// entities are `Without<CardEntity>` sprites owned solely by this chain —
+/// systems that animate other entity domains (e.g. the win-summary camera
+/// shake) declare themselves `.ambiguous_with(HintGhostFx)` (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct HintGhostFx;
+
 impl Plugin for FeedbackAnimPlugin {
     fn build(&self, app: &mut App) {
         // Register the events this plugin consumes so it can run in isolation
@@ -207,23 +224,70 @@ impl Plugin for FeedbackAnimPlugin {
             .add_message::<MoveRejectedEvent>()
             .add_message::<NewGameRequestEvent>()
             .add_message::<FoundationCompletedEvent>()
+            .add_message::<HintVisualEvent>()
+            .add_message::<StateChangedEvent>()
             .add_message::<RequestRedraw>()
+            .configure_sets(
+                Update,
+                FeedbackFx
+                    .after(GameMutation)
+                    .after(crate::animation_plugin::AnimFx)
+                    // HUD text pulses are disjoint from the card/marker
+                    // entities this set animates (see UiTextFx ×
+                    // BoardVisuals, #143).
+                    .ambiguous_with(crate::ui_theme::UiTextFx),
+            )
             .add_systems(
                 Update,
                 (
-                    start_shake_anim.after(GameMutation),
+                    // Reads only the reduce-motion flag; a frame of lag is
+                    // invisible (#143).
+                    start_shake_anim.ambiguous_with(crate::settings_plugin::SettingsAccess),
                     tick_shake_anim,
-                    start_settle_anim.after(GameMutation),
+                    start_settle_anim,
                     // tick_foundation_flourish writes the full Transform.scale
                     // (Vec3); tick_settle_anim writes only scale.y on top of
                     // it. Ordering ensures the settle's y-only write always
                     // applies last so it wins on the ~0.15 s overlap when both
                     // components are present on the same King entity.
-                    tick_foundation_flourish.before(tick_settle_anim),
+                    tick_foundation_flourish,
                     tick_settle_anim,
-                    start_deal_anim.after(GameMutation),
-                    start_foundation_flourish.after(GameMutation),
-                ),
+                    start_deal_anim,
+                    start_foundation_flourish,
+                )
+                    .chain()
+                    .in_set(FeedbackFx),
+            )
+            // Hint ghost (Phase H): the spawn reads card Transform/Sprite,
+            // so it orders after the board painters; the tick only touches
+            // ghost entities (Without<CardEntity>) and stays conflict-free.
+            .add_systems(
+                Update,
+                (
+                    spawn_hint_ghost
+                        .after(GameMutation)
+                        .after(crate::card_plugin::BoardVisuals),
+                    tick_hint_ghosts,
+                    despawn_hint_ghosts_on_state_change.after(GameMutation),
+                )
+                    .chain()
+                    .in_set(HintGhostFx)
+                    // The spawn reads card Sprites the marker painters (theme
+                    // apply, pile highlights) also write — those settle first.
+                    // Ghost entities are Without<CardEntity> and never HUD
+                    // chrome, and the spawn reads only the reduce-motion flag
+                    // (frame-lag invisible) (#143).
+                    .after(crate::table_plugin::MarkerVisuals)
+                    // …and the card tweens/slides, whose Transform writes
+                    // the spawn snapshot must not race.
+                    .after(crate::card_animation::CardTweenFx)
+                    // FeedbackFx (deal slide, shake) is the last Transform
+                    // writer on the spine — the ghost snapshot reads after
+                    // the whole visual pipeline has settled.
+                    .after(FeedbackFx)
+                    .ambiguous_with(crate::ui_theme::UiTextFx)
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             );
     }
 }
@@ -664,6 +728,147 @@ fn pile_cards(
     }
 }
 
+// ---------------------------------------------------------------------------
+// Phase H — hint ghost-motion preview
+// ---------------------------------------------------------------------------
+
+/// Duration of one ghost glide from the hinted card to its destination.
+const HINT_GHOST_PASS_SECS: f32 = 0.7;
+/// How many glides one hint plays before the ghost despawns. Two reads
+/// as "this move, over there" without outstaying the 2 s static
+/// highlight it accompanies.
+const HINT_GHOST_PASSES: f32 = 2.0;
+/// Ghost translucency — clearly a projection, never mistakable for the
+/// real card.
+const HINT_GHOST_ALPHA: f32 = 0.45;
+/// Ghost render depth: above every settled pile (~1.04 max) and the
+/// in-flight `CardAnim` lift (50), below a dragged card (500).
+const HINT_GHOST_Z: f32 = 400.0;
+
+/// A translucent copy of the hinted card gliding to the suggested
+/// destination (Phase H). Purely decorative — despawned by timer, by a
+/// newer hint, or by any state change.
+#[derive(Component, Debug)]
+pub struct HintGhost {
+    start: Vec3,
+    target: Vec3,
+    elapsed: f32,
+}
+
+/// Normalised progress of the current glide pass, restarting from the
+/// source each pass. Pure for unit testing.
+fn hint_ghost_pass_t(elapsed: f32) -> f32 {
+    (elapsed % HINT_GHOST_PASS_SECS) / HINT_GHOST_PASS_SECS
+}
+
+/// Ghost alpha at `pass_t` — full strength for most of the glide, then
+/// fading over the last 20 % so the loop restart reads as a repeat
+/// rather than a teleport. Pure for unit testing.
+fn hint_ghost_alpha(pass_t: f32) -> f32 {
+    let fade_in_tail = ((pass_t - 0.8) / 0.2).clamp(0.0, 1.0);
+    HINT_GHOST_ALPHA * (1.0 - fade_in_tail)
+}
+
+/// Spawns the ghost when a hint fires. The static highlights (source
+/// card + gold destination pile) still spawn regardless; under
+/// reduce-motion they are the whole story and no ghost appears
+/// (`design-system.md` §Accessibility).
+#[allow(clippy::too_many_arguments)]
+fn spawn_hint_ghost(
+    mut events: MessageReader<HintVisualEvent>,
+    settings: Option<Res<SettingsResource>>,
+    index: Option<Res<CardEntityIndex>>,
+    layout: Option<Res<LayoutResource>>,
+    cards: Query<(&Transform, &Sprite), With<CardEntity>>,
+    existing: Query<Entity, With<HintGhost>>,
+    mut commands: Commands,
+) {
+    if events.is_empty() {
+        return;
+    }
+    if settings.is_some_and(|s| s.0.reduce_motion_mode) {
+        events.clear();
+        return;
+    }
+    let (Some(index), Some(layout)) = (index, layout) else {
+        events.clear();
+        return;
+    };
+    for ev in events.read() {
+        // A fresh hint replaces any ghost still in flight.
+        for entity in &existing {
+            commands.entity(entity).despawn();
+        }
+        let Some(card_entity) = index.get(&ev.source_card) else {
+            continue;
+        };
+        let Ok((transform, sprite)) = cards.get(card_entity) else {
+            continue;
+        };
+        let Some(&dest) = layout.0.pile_positions.get(&ev.dest_pile) else {
+            continue;
+        };
+        let start = transform.translation.truncate().extend(HINT_GHOST_Z);
+        let mut ghost_sprite = sprite.clone();
+        ghost_sprite.color = ghost_sprite.color.with_alpha(HINT_GHOST_ALPHA);
+        commands.spawn((
+            HintGhost {
+                start,
+                target: dest.extend(HINT_GHOST_Z),
+                elapsed: 0.0,
+            },
+            ghost_sprite,
+            Transform::from_translation(start),
+        ));
+    }
+}
+
+/// Advances every ghost: eased glide per pass, tail fade, despawn after
+/// [`HINT_GHOST_PASSES`]. Frozen while paused, like every other
+/// decorative animation.
+#[allow(clippy::type_complexity)]
+fn tick_hint_ghosts(
+    time: Res<Time>,
+    paused: Option<Res<PausedResource>>,
+    mut ghosts: Query<
+        (Entity, &mut HintGhost, &mut Transform, &mut Sprite),
+        (Without<CardEntity>, Without<PileMarker>),
+    >,
+    mut commands: Commands,
+) {
+    if paused.is_some_and(|p| p.0) {
+        return;
+    }
+    let dt = time.delta_secs();
+    for (entity, mut ghost, mut transform, mut sprite) in ghosts.iter_mut() {
+        ghost.elapsed += dt;
+        if ghost.elapsed >= HINT_GHOST_PASS_SECS * HINT_GHOST_PASSES {
+            commands.entity(entity).despawn();
+            continue;
+        }
+        let pass_t = hint_ghost_pass_t(ghost.elapsed);
+        let eased = sample_curve(MotionCurve::SmoothSnap, pass_t);
+        transform.translation = ghost.start.lerp(ghost.target, eased);
+        sprite.color = sprite.color.with_alpha(hint_ghost_alpha(pass_t));
+    }
+}
+
+/// A ghost previews a move against the *current* board; the moment the
+/// board changes (move, undo, draw, new game) it is stale and vanishes.
+fn despawn_hint_ghosts_on_state_change(
+    mut events: MessageReader<StateChangedEvent>,
+    ghosts: Query<Entity, With<HintGhost>>,
+    mut commands: Commands,
+) {
+    if events.is_empty() {
+        return;
+    }
+    events.clear();
+    for entity in &ghosts {
+        commands.entity(entity).despawn();
+    }
+}
+
 // ---------------------------------------------------------------------------
 // Unit tests (pure functions only — no Bevy world required)
 // ---------------------------------------------------------------------------
@@ -955,4 +1160,147 @@ mod tests {
             "FoundationFlourish must not be inserted under reduce-motion"
         );
     }
+
+    // -----------------------------------------------------------------------
+    // Phase H — hint ghost-motion preview
+    // -----------------------------------------------------------------------
+
+    #[test]
+    fn hint_ghost_pass_t_restarts_each_pass() {
+        assert_eq!(hint_ghost_pass_t(0.0), 0.0);
+        // Just past one full pass, progress wraps back near zero.
+        assert!(hint_ghost_pass_t(HINT_GHOST_PASS_SECS + 0.01) < 0.1);
+    }
+
+    #[test]
+    fn hint_ghost_alpha_fades_only_in_the_tail() {
+        assert_eq!(hint_ghost_alpha(0.0), HINT_GHOST_ALPHA);
+        assert_eq!(hint_ghost_alpha(0.79), HINT_GHOST_ALPHA);
+        assert!(hint_ghost_alpha(0.9) < HINT_GHOST_ALPHA);
+        assert!(hint_ghost_alpha(1.0).abs() < 1e-6);
+    }
+
+    /// App with one indexed card entity and a real layout, ready to
+    /// receive `HintVisualEvent`s.
+    fn ghost_app(reduce_motion: bool) -> (App, Card) {
+        use solitaire_core::{Deck, Rank, Suit};
+
+        let mut app = App::new();
+        app.add_plugins(MinimalPlugins)
+            .add_plugins(FeedbackAnimPlugin);
+        // Sibling systems in the plugin take GameStateResource
+        // non-optionally; give them a fresh deal.
+        app.insert_resource(GameStateResource(
+            solitaire_core::game_state::GameState::new(1, solitaire_core::DrawStockConfig::DrawOne),
+        ));
+        app.insert_resource(SettingsResource(solitaire_data::Settings {
+            reduce_motion_mode: reduce_motion,
+            ..Default::default()
+        }));
+
+        let card = Card::new(Deck::Deck1, Suit::Spades, Rank::Ace);
+        let entity = app
+            .world_mut()
+            .spawn((
+                CardEntity { card: card.clone() },
+                Sprite::default(),
+                Transform::from_xyz(-100.0, 40.0, 1.0),
+            ))
+            .id();
+        let mut index = CardEntityIndex::default();
+        index.0.insert(card.clone(), entity);
+        app.insert_resource(index);
+        app.insert_resource(LayoutResource(crate::layout::compute_layout(
+            Vec2::new(1280.0, 720.0),
+            0.0,
+            0.0,
+            true,
+        )));
+        app.update();
+        (app, card)
+    }
+
+    fn fire_hint(app: &mut App, card: Card) {
+        use solitaire_core::Tableau;
+        app.world_mut().write_message(HintVisualEvent {
+            source_card: card,
+            dest_pile: KlondikePile::Tableau(Tableau::Tableau2),
+        });
+        app.update();
+    }
+
+    fn ghost_count(app: &mut App) -> usize {
+        app.world_mut()
+            .query::<&HintGhost>()
+            .iter(app.world())
+            .count()
+    }
+
+    #[test]
+    fn hint_event_spawns_one_ghost_at_the_source_card() {
+        let (mut app, card) = ghost_app(false);
+        fire_hint(&mut app, card);
+
+        assert_eq!(ghost_count(&mut app), 1, "hint must spawn one ghost");
+        let transform = app
+            .world_mut()
+            .query_filtered::<&Transform, With<HintGhost>>()
+            .single(app.world())
+            .expect("ghost transform");
+        // The tick system may have advanced the ghost by one real-time
+        // frame already; assert it is still essentially at the source.
+        assert!(
+            transform
+                .translation
+                .truncate()
+                .distance(Vec2::new(-100.0, 40.0))
+                < 5.0,
+            "ghost must start at the hinted card, got {:?}",
+            transform.translation
+        );
+        assert_eq!(transform.translation.z, HINT_GHOST_Z);
+    }
+
+    #[test]
+    fn hint_ghost_suppressed_under_reduce_motion() {
+        let (mut app, card) = ghost_app(true);
+        fire_hint(&mut app, card);
+
+        assert_eq!(
+            ghost_count(&mut app),
+            0,
+            "no ghost may spawn under reduce-motion; the static highlight is the whole story"
+        );
+    }
+
+    #[test]
+    fn state_change_despawns_the_ghost() {
+        let (mut app, card) = ghost_app(false);
+        fire_hint(&mut app, card);
+        assert_eq!(ghost_count(&mut app), 1);
+
+        app.world_mut().write_message(StateChangedEvent);
+        app.update();
+        app.update();
+
+        assert_eq!(
+            ghost_count(&mut app),
+            0,
+            "a board change makes the previewed move stale — the ghost must vanish"
+        );
+    }
+
+    #[test]
+    fn second_hint_replaces_the_first_ghost() {
+        let (mut app, card) = ghost_app(false);
+        fire_hint(&mut app, card.clone());
+        fire_hint(&mut app, card);
+        app.update();
+
+        assert_eq!(
+            ghost_count(&mut app),
+            1,
+            "re-hinting must replace the in-flight ghost, not stack a second"
+        );
+    }
 }

solitaire_engine/src/game_plugin/mod.rs

@@ -99,6 +99,38 @@ pub struct DrawRequestWriters;
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct InfoToastWriters;
 
+/// Self-ambiguous club for writers of `MoveRequestEvent` (drag drops, stock
+/// clicks, radial menu, selection keys, replay step button). Consumers drain
+/// the whole queue — append order is meaningless (#143). Same rules as
+/// [`NewGameRequestWriters`]: do NOT hang ordering edges off this set.
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MoveRequestWriters;
+
+/// Self-ambiguous club for writers of `WarningToastEvent` (daily-expiry
+/// warning, leaderboard opt-in/out failure polls). The toast pipeline
+/// drains the whole queue — append order is meaningless (#143). Same
+/// rules as [`InfoToastWriters`].
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WarningToastWriters;
+
+/// Set + self-ambiguous club for the mode-start request handlers (challenge,
+/// daily, time-attack, play-by-seed, difficulty). Each drains its own
+/// request stream and resets `GameStateResource` for its mode; only one
+/// stream carries an event on any real frame, so member order is irrelevant
+/// (club), while the set as a whole runs between the stats abandon-recorder
+/// ([`crate::stats_plugin::AbandonRecord`], which must read the old game
+/// first) and [`GameMutation`] (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ModeStart;
+
+/// Set wrapping `GamePlugin`'s pre-mutation game-state spine (elapsed-time
+/// tick, settings sync, restore prompt). Sits between
+/// [`crate::settings_plugin::SettingsMutation`] and [`GameMutation`]; other
+/// pre-mutation readers of `GameStateResource` (e.g. the stats
+/// abandon-recorder) order themselves `.after(PreMutation)` (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PreMutation;
+
 /// Persistence path for the in-progress game state file. `None` disables I/O.
 #[derive(Resource, Debug, Clone)]
 pub struct GameStatePath(pub Option<PathBuf>);
@@ -267,7 +299,14 @@ impl Plugin for GamePlugin {
                     .in_set(InfoToastWriters)
                     .ambiguous_with(InfoToastWriters),
             )
-            .add_systems(Update, record_replay_on_win.after(GameMutation))
+            .add_systems(
+                Update,
+                record_replay_on_win
+                    .after(GameMutation)
+                    // Before the playback skip-recorder (which runs after
+                    // AutoComplete) — both touch RecordingReplay (#143).
+                    .before(crate::auto_complete_plugin::AutoComplete),
+            )
             .add_systems(
                 Update,
                 (
@@ -301,9 +340,20 @@ impl Plugin for GamePlugin {
                         .ambiguous_with(NewGameRequestWriters),
                 )
                     .chain()
+                    .in_set(PreMutation),
+            )
+            .configure_sets(
+                Update,
+                PreMutation
                     .after(crate::settings_plugin::SettingsMutation)
                     .before(GameMutation),
             )
+            .configure_sets(
+                Update,
+                ModeStart
+                    .after(crate::stats_plugin::AbandonRecord)
+                    .before(GameMutation),
+            )
             .init_resource::<AutoSaveTimer>()
             .add_systems(Update, auto_save_game_state.after(GameMutation))
             .add_systems(Last, save_game_state_on_exit);

solitaire_engine/src/help_plugin.rs

@@ -54,12 +54,23 @@ impl Plugin for HelpPlugin {
             .add_message::<TouchInput>()
             .add_systems(
                 Update,
-                (
-                    toggle_help_screen,
-                    handle_help_close_button,
-                    scroll_help_panel,
-                    crate::ui_modal::touch_scroll_panel::<HelpScrollable>,
-                ),
+                (toggle_help_screen, handle_help_close_button)
+                    .chain()
+                    // FocusKeys consumes Esc after the modal handlers
+                    // (mirrors toggle_settings_screen, #143).
+                    .before(crate::ui_focus::FocusKeys),
+            )
+            .add_systems(
+                Update,
+                scroll_help_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            )
+            .add_systems(
+                Update,
+                crate::ui_modal::touch_scroll_panel::<HelpScrollable>
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
             );
     }
 }

solitaire_engine/src/home_plugin.rs

@@ -334,19 +334,45 @@ impl Plugin for HomePlugin {
                     spawn_home_on_launch,
                     toggle_home_screen,
                     attach_focusable_to_home_mode_cards,
-                    handle_home_card_click,
-                    handle_home_new_game_hero,
+                    handle_home_card_click
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
+                    handle_home_new_game_hero
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
                     handle_home_cancel_button,
-                    handle_home_profile_chip,
+                    handle_home_profile_chip
+                        .in_set(crate::profile_plugin::ProfileToggleWriters)
+                        .ambiguous_with(crate::profile_plugin::ProfileToggleWriters),
                     handle_home_draw_mode_buttons,
                     handle_home_winnable_toggle,
                     handle_home_deal_options_toggle,
-                    handle_home_difficulty_chip_click,
-                    handle_home_digit_keys,
+                    handle_home_difficulty_chip_click
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
+                    handle_home_digit_keys
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                        .before(crate::ui_focus::FocusKeys),
                 )
-                    .chain(),
+                    .chain()
+                    // The home context repaints from this frame's settled
+                    // progress/stats/achievements; settings access joins the
+                    // screen-plugin club (#143).
+                    .after(crate::progress_plugin::ProgressUpdate)
+                    .after(crate::stats_plugin::StatsUpdate)
+                    .after(crate::achievement_plugin::AchievementEval)
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             )
-            .add_systems(Update, scroll_home_panel);
+            .add_systems(
+                Update,
+                scroll_home_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            );
     }
 }
 
@@ -480,6 +506,10 @@ fn persist_last_mode(
 ///   owns the launch beat; Home appearing underneath it stacked two
 ///   modals (Phase H fix; spotted in the v0.44.0 emulator smoke). Home
 ///   spawns on the first frame after the player finishes or skips.
+/// * The What's-new card (Phase I) must have had its beat —
+///   [`crate::whats_new_plugin::WhatsNewPending`] released — so an
+///   upgrade's release notes get read before the mode picker lands on
+///   top of them.
 /// * `HomeScreen` must not already exist (defensive — e.g. the player
 ///   pressed `M` between ticks).
 /// * `LaunchHomeShown` flips to `true` after the first spawn so this
@@ -494,6 +524,7 @@ fn spawn_home_on_launch(
     restore_prompts: Query<(), With<crate::game_plugin::RestorePromptScreen>>,
     pending_restore: Option<Res<crate::game_plugin::PendingRestoredGame>>,
     onboarding: Query<(), With<crate::onboarding_plugin::OnboardingScreen>>,
+    whats_new: Option<Res<crate::whats_new_plugin::WhatsNewPending>>,
     existing: Query<(), With<HomeScreen>>,
     sources: HomeSpawnSources,
     mut deal_expanded: ResMut<DealOptionsExpanded>,
@@ -503,6 +534,7 @@ fn spawn_home_on_launch(
         || !restore_prompts.is_empty()
         || pending_restore.as_ref().is_some_and(|p| p.0.is_some())
         || !onboarding.is_empty()
+        || whats_new.as_ref().is_some_and(|w| w.0)
         || sources
             .settings
             .as_ref()

solitaire_engine/src/hotkeys.rs

@@ -0,0 +1,169 @@
+//! Single source of truth for the desktop keyboard bindings (Phase J).
+//!
+//! Two static hotkey tables had already diverged (onboarding's slide
+//! and Help's controls reference); every future drift multiplies. This
+//! module owns THE table: the onboarding slide renders the
+//! [`HotkeyRow::essential`] subset, the hold-`/` cheat sheet
+//! ([`crate::cheat_sheet_plugin`]) renders everything.
+//!
+//! The table is hand-maintained but **pinned by test** against the
+//! handlers that actually consume each key — adding a binding without
+//! updating this table (or vice versa) is designed to fail review, not
+//! runtime. A registry generated from the input systems themselves is
+//! the eventual ideal; this is the honest 90 % at 1 % of the cost.
+
+/// One row of the hotkey table.
+#[derive(Debug, Clone, Copy)]
+pub struct HotkeyRow {
+    /// Display form of the key(s), e.g. `"D / Space"`.
+    pub keys: &'static str,
+    /// One-line action description.
+    pub description: &'static str,
+    /// `true` for the beginner-relevant subset the onboarding slide
+    /// shows; the cheat sheet always shows every row.
+    pub essential: bool,
+}
+
+/// Every desktop keyboard binding, in teaching order.
+pub const HOTKEYS: &[HotkeyRow] = &[
+    HotkeyRow {
+        keys: "D / Space",
+        description: "Draw from stock",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "U",
+        description: "Undo last move (hold to repeat)",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "H",
+        description: "Hint (repeat to cycle alternatives)",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "Tab → Enter",
+        description: "Pick a card; arrows pick where; Enter to drop",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "N",
+        description: "New Classic game",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "M",
+        description: "Open Home (then 1–6 to pick a mode)",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "Esc",
+        description: "Pause / resume; close the top dialog",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "F1",
+        description: "Help / controls",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "S",
+        description: "Stats & progression",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "A",
+        description: "Achievements",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "O",
+        description: "Settings",
+        essential: true,
+    },
+    HotkeyRow {
+        keys: "P",
+        description: "Profile",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "L",
+        description: "Leaderboard",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "C",
+        description: "Daily Challenge",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "Z",
+        description: "Zen mode",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "X",
+        description: "Challenge mode",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "T",
+        description: "Time Attack",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "G",
+        description: "Give up the current deal",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "[ / ]",
+        description: "Volume down / up",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "F11",
+        description: "Toggle fullscreen",
+        essential: false,
+    },
+    HotkeyRow {
+        keys: "/ (hold)",
+        description: "This cheat sheet",
+        essential: false,
+    },
+];
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn table_is_populated_and_well_formed() {
+        assert!(!HOTKEYS.is_empty());
+        for row in HOTKEYS {
+            assert!(!row.keys.trim().is_empty(), "empty keys cell");
+            assert!(
+                !row.description.trim().is_empty(),
+                "empty description for {}",
+                row.keys
+            );
+        }
+    }
+
+    #[test]
+    fn essential_subset_is_a_teachable_size() {
+        let essentials = HOTKEYS.iter().filter(|r| r.essential).count();
+        assert!(
+            (6..=12).contains(&essentials),
+            "the onboarding slide wants a skimmable essential set, got {essentials}"
+        );
+    }
+
+    #[test]
+    fn keys_cells_are_unique() {
+        let mut seen = std::collections::HashSet::new();
+        for row in HOTKEYS {
+            assert!(seen.insert(row.keys), "duplicate hotkey row: {}", row.keys);
+        }
+    }
+}

solitaire_engine/src/hud_plugin/fx.rs

@@ -109,12 +109,19 @@ pub(super) fn apply_action_fade(
 /// Visual feedback for every action button — paints idle / hover / pressed
 /// states by mutating `BackgroundColor` whenever the interaction state
 /// changes. One query covers all action buttons via the shared
-/// `ActionButton` marker.
+/// `ActionButton` marker. Glass tab-bar buttons are excluded: they carry
+/// their own per-button colour triple and are painted by
+/// `paint_glass_tab_buttons` instead (this system's opaque `ACTION_BTN_*`
+/// fills would destroy the translucent glass look).
 #[allow(clippy::type_complexity)]
 pub(super) fn paint_action_buttons(
     mut buttons: Query<
         (&Interaction, &mut BackgroundColor),
-        (With<ActionButton>, Changed<Interaction>),
+        (
+            With<ActionButton>,
+            Without<GlassTabButton>,
+            Changed<Interaction>,
+        ),
     >,
 ) {
     for (interaction, mut bg) in &mut buttons {

solitaire_engine/src/hud_plugin/mod.rs

@@ -12,11 +12,13 @@ use bevy::window::WindowResized;
 mod fx;
 mod interaction;
 mod spawn;
+pub(crate) mod tab_bar;
 mod updates;
 
 pub use fx::*;
 use interaction::*;
 use spawn::*;
+use tab_bar::*;
 use updates::*;
 
 // On wasm32 AvatarPlugin is gated out; define a placeholder type so the
@@ -515,13 +517,31 @@ impl Plugin for HudPlugin {
                 Update,
                 (restore_hud_on_modal, apply_hud_visibility)
                     .chain()
-                    .before(LayoutSystem::UpdateOnResize),
+                    .before(LayoutSystem::UpdateOnResize)
+                    // Toggles Visibility on HUD chrome roots only — joins
+                    // the chrome club (#143).
+                    .in_set(UiTextFx)
+                    .ambiguous_with(UiTextFx),
             )
             .add_systems(
                 Update,
                 (
-                    update_hud_avatar.after(crate::settings_plugin::SettingsMutation),
-                    handle_avatar_button.ambiguous_with(HudButtons),
+                    update_hud_avatar
+                        // Same-frame-exact after the settings spine, so NOT
+                        // a SettingsAccess member — but the club's readers
+                        // and the home deal-option writers touch settings
+                        // fields the avatar never reads (#143).
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess)
+                        .after(crate::settings_plugin::SettingsMutation)
+                        // Two more settings writers arrived with the wider
+                        // ambiguity cluster: the pause overlay's draw-mode
+                        // toggle and the achievement onboarding flag (#143).
+                        .after(crate::pause_plugin::PauseMutation)
+                        .after(crate::game_plugin::InfoToastWriters),
+                    handle_avatar_button
+                        .ambiguous_with(HudButtons)
+                        .in_set(crate::profile_plugin::ProfileToggleWriters)
+                        .ambiguous_with(crate::profile_plugin::ProfileToggleWriters),
                 ),
             )
             .add_systems(
@@ -536,7 +556,11 @@ impl Plugin for HudPlugin {
             // the board painters that resize card/label text (#143).
             .add_systems(
                 Update,
-                update_hud_typography.after(crate::card_plugin::BoardVisuals),
+                update_hud_typography
+                    .after(crate::card_plugin::BoardVisuals)
+                    // Writes HUD TextFont only — chrome club (#143).
+                    .in_set(UiTextFx)
+                    .ambiguous_with(UiTextFx),
             )
             .add_systems(
                 Update,
@@ -549,16 +573,26 @@ impl Plugin for HudPlugin {
                     .after(GameMutation)
                     .in_set(UiTextFx)
                     .ambiguous_with(UiTextFx)
-                    .ambiguous_with(crate::card_plugin::BoardVisuals),
+                    .ambiguous_with(crate::card_plugin::BoardVisuals)
+                    // Reads only the reduce-motion flag; a frame of lag is
+                    // invisible (#143).
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             )
             .add_systems(
                 Update,
                 (start_streak_flourish, advance_streak_flourish)
                     .chain()
                     .after(GameMutation)
+                    // Reads the streak-milestone events StatsUpdate emits.
+                    .after(crate::stats_plugin::StatsUpdate)
                     .in_set(UiTextFx)
                     .ambiguous_with(UiTextFx)
-                    .ambiguous_with(crate::card_plugin::BoardVisuals),
+                    .ambiguous_with(crate::card_plugin::BoardVisuals)
+                    // Reads only the reduce-motion flag; a frame of lag is
+                    // invisible (#143).
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             )
             .add_systems(
                 Update,
@@ -582,19 +616,48 @@ impl Plugin for HudPlugin {
                     handle_help_button,
                     handle_hint_button
                         .after(GameMutation)
+                        // A press cancels/spawns the solver task before
+                        // this frame's drop/poll pass (#143).
+                        .before(crate::pending_hint::PendingHint)
                         .in_set(crate::game_plugin::InfoToastWriters)
                         .ambiguous_with(crate::game_plugin::InfoToastWriters),
-                    handle_modes_button,
+                    // The modes/menu popovers repaint the player level from
+                    // ProgressResource — read it after this frame's XP award
+                    // settles (#143).
+                    handle_modes_button
+                        .after(crate::progress_plugin::ProgressUpdate)
+                        .after(crate::achievement_plugin::AchievementEval),
                     handle_mode_option_click
                         .in_set(NewGameRequestWriters)
                         .ambiguous_with(NewGameRequestWriters),
                     handle_modes_backdrop_click,
                     close_modes_popover_on_escape,
                     handle_menu_button,
-                    handle_menu_option_click,
+                    handle_menu_option_click
+                        .after(crate::progress_plugin::ProgressUpdate)
+                        .after(crate::achievement_plugin::AchievementEval)
+                        .in_set(crate::profile_plugin::ProfileToggleWriters)
+                        .ambiguous_with(crate::profile_plugin::ProfileToggleWriters),
                     handle_menu_backdrop_click,
                     close_menu_popover_on_escape,
                     paint_action_buttons,
+                    paint_glass_tab_buttons,
+                    drive_tab_expansion,
+                    // Writes tab-label TextColor and reads TextFont — entity-
+                    // disjoint from the UiTextFx readout writers (tab labels
+                    // vs HUD readouts), which Bevy can't prove, so declare it.
+                    animate_tab_expansion
+                        .ambiguous_with(UiTextFx)
+                        // Tab-label fonts are never card/corner-label fonts.
+                        .ambiguous_with(crate::card_plugin::BoardVisuals)
+                        // Reads only reduce-motion; a frame of lag is
+                        // invisible, so it joins the settings-reader club.
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
+                    // Reads only reduce-motion — settings-reader club (#143).
+                    duck_tab_bar_during_drag
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
                 )
                     .chain()
                     .in_set(HudButtons)

solitaire_engine/src/hud_plugin/spawn.rs

@@ -360,6 +360,7 @@ pub(super) fn handle_avatar_button(
 pub(super) fn spawn_action_buttons(
     font_res: Option<Res<FontResource>>,
     windows: Query<&Window>,
+    images: Option<ResMut<Assets<Image>>>,
     mut commands: Commands,
 ) {
     let action_font_size =
@@ -370,9 +371,18 @@ pub(super) fn spawn_action_buttons(
         ..default()
     };
 
-    // Bottom bar: full-width, centered, sits above the gesture-navigation zone.
+    // Touch layout: the floating glass tab bar (pill + circular Menu).
+    // `Assets<Image>` is absent under `MinimalPlugins`; `rasterize_into`
+    // returning `None` switches the bar to its text-fallback form.
+    if USE_TOUCH_UI_LAYOUT {
+        let icons = images.and_then(|mut imgs| TabIcons::rasterize_into(&mut imgs));
+        spawn_glass_tab_bar(&mut commands, &font, icons.as_ref());
+        return;
+    }
+
+    // Desktop bottom bar: full-width, centered, docked to the bottom edge.
     // `SafeAreaAnchoredBottom` applies the correct logical-pixel inset once
-    // Android reports it (frames 1-3); initial value is 0.0.
+    // the platform reports it; initial value is 0.0.
     commands
         .spawn((
             Node {
@@ -400,73 +410,10 @@ pub(super) fn spawn_action_buttons(
             HudActionBar,
         ))
         .with_children(|row| {
-            if USE_TOUCH_UI_LAYOUT {
-                spawn_touch_action_bar(row, &font);
-            } else {
             spawn_desktop_action_bar(row, &font);
-            }
         });
 }
 
-/// Phase F touch action bar — five buttons, three of them big.
-///
-/// The core gameplay trio (**Undo · Draw · Hint**) gets enlarged
-/// thumb-reach targets; Menu and Pause stay compact at the edges. The
-/// utility actions the desktop bar carries are reachable elsewhere on
-/// touch and are deliberately absent here: Help lives in Menu → System,
-/// mode switching lives on the Home screen (Phase B), and New Game is
-/// Home's hero button. Draw duplicates the stock-pile tap so the most
-/// frequent action of all no longer requires reaching the top half of a
-/// tall folded screen.
-pub(super) fn spawn_touch_action_bar(row: &mut ChildSpawnerCommands, font: &TextFont) {
-    // The trailing `order` argument feeds `Focusable { group: Hud, order }`
-    // so Tab (external keyboard) cycles the bar in visual reading order.
-    spawn_action_button(
-        row,
-        MenuButton,
-        "Menu",
-        None,
-        "Open Home, Stats, Achievements, Profile, Settings, or Leaderboard.",
-        font,
-        0,
-        TEXT_SECONDARY,
-    );
-    spawn_primary_action_button(
-        row,
-        UndoButton,
-        "Undo",
-        "Take back your last move. Hold to keep undoing. Costs points and blocks No Undo.",
-        font,
-        1,
-    );
-    spawn_primary_action_button(
-        row,
-        DrawButton,
-        "Draw",
-        "Draw from the stock — same as tapping the deck.",
-        font,
-        2,
-    );
-    spawn_primary_action_button(
-        row,
-        HintButton,
-        TOUCH_HINT_LABEL,
-        "Highlight a suggested move. Cycles through alternatives on repeat taps.",
-        font,
-        3,
-    );
-    spawn_action_button(
-        row,
-        PauseButton,
-        "Pause",
-        None,
-        "Pause the game and freeze the timer.",
-        font,
-        4,
-        TEXT_SECONDARY,
-    );
-}
-
 /// Desktop action bar — unchanged by Phase F (decision 5: the touch bar
 /// is touch-only). All seven actions, uniform sizing.
 pub(super) fn spawn_desktop_action_bar(row: &mut ChildSpawnerCommands, font: &TextFont) {
@@ -585,44 +532,9 @@ pub(super) fn spawn_action_button<M: Component>(
     );
 }
 
-/// Enlarged variant for the touch bar's core gameplay trio (Phase F):
-/// bigger padding / minimum target and a scaled-up label so Undo, Draw,
-/// and Hint read (and hit) as the primary actions. Hotkey chips are
-/// irrelevant on touch, so the variant takes none.
-pub(super) fn spawn_primary_action_button<M: Component>(
-    row: &mut ChildSpawnerCommands,
-    marker: M,
-    label: &str,
-    tooltip: &'static str,
-    font: &TextFont,
-    order: i32,
-) {
-    let (pad, min_w, min_h) = primary_action_button_metrics();
-    let primary_font = TextFont {
-        font: font.font.clone(),
-        // 1.35× the bar's responsive size, capped so landscape tablets
-        // don't blow the row height out.
-        font_size: (font.font_size * 1.35).min(24.0),
-        ..default()
-    };
-    spawn_action_button_sized(
-        row,
-        marker,
-        label,
-        None,
-        tooltip,
-        &primary_font,
-        order,
-        TEXT_PRIMARY,
-        pad,
-        min_w,
-        min_h,
-    );
-}
-
-/// Shared body of [`spawn_action_button`] / [`spawn_primary_action_button`]
-/// — one place owns the component set so `paint_action_buttons`, tooltips,
-/// and the focus ring treat every bar button identically.
+/// Shared body of [`spawn_action_button`] — one place owns the component
+/// set so `paint_action_buttons`, tooltips, and the focus ring treat every
+/// bar button identically.
 #[allow(clippy::too_many_arguments)]
 fn spawn_action_button_sized<M: Component>(
     row: &mut ChildSpawnerCommands,

solitaire_engine/src/hud_plugin/tab_bar.rs

@@ -0,0 +1,529 @@
+//! Floating "liquid glass" touch tab bar — layout and animation.
+//!
+//! Replaces the docked full-width touch action bar (Phase F) with an
+//! iOS-26-style floating arrangement: a pill of icon buttons hovering
+//! above the bottom edge, plus a detached circular Menu button to its
+//! right. The *visual treatment* (translucent sheen, specular rim, drop
+//! shadow) lives in [`crate::ui_glass`]; this module owns only geometry,
+//! button wiring, and the expand/collapse label animation, so the glass
+//! material can be swapped without touching layout.
+//!
+//! Interaction compatibility: every button keeps the same marker
+//! components as the old bar (`UndoButton`, `DrawButton`, …) plus
+//! `ActionButton`, `Button`, `Tooltip`, and `Focusable`, so the click
+//! handlers, tooltips, focus ring, and the tap-to-toggle chrome guard in
+//! `interaction.rs` all work unchanged.
+//!
+//! Expansion model (user decision, 2026-07-15): **Draw** — the most
+//! frequent action — is the persistently-expanded "active" pill showing
+//! icon + label; the other buttons are icon-only and reveal their label
+//! with a width-animated slide while pressed.
+
+use super::*;
+use crate::assets::hud_icon_svg::HudIcon;
+use crate::ui_glass::{GLASS_BORDER_PX, glass_surface};
+use crate::ui_theme::{ACCENT_PRIMARY_HOVER, SPACE_3};
+use bevy::text::{LineBreak, TextLayout};
+use bevy::ui::{Overflow, UiTransform, Val2};
+
+use crate::resources::DragState;
+use crate::safe_area::SafeAreaInsets;
+
+/// Height of both the pill and the circular Menu button, in logical px.
+/// 64 keeps the inner 48-px buttons comfortably past the 44-px touch
+/// floor with 8 px of glass around them.
+pub(crate) const TAB_BAR_HEIGHT: f32 = 64.0;
+
+/// Gap between the bar and the bottom screen edge (the "floating" margin;
+/// the Android gesture-bar inset is added on top by `SafeAreaAnchoredBottom`).
+const TAB_BAR_MARGIN: f32 = SPACE_3;
+
+/// Vertical space UI stacked above the bar (the toast stack) must clear:
+/// floating margin + bar height + one spacing step of breathing room.
+pub(crate) const TAB_BAR_CLEARANCE_PX: f32 = TAB_BAR_MARGIN + TAB_BAR_HEIGHT + SPACE_2;
+
+/// Diameter of a button inside the pill (and its fully-round radius ×2).
+const TAB_BUTTON_SIZE: f32 = 48.0;
+
+/// Displayed icon size in logical px (texture is rasterised larger; see
+/// `assets::hud_icon_svg::HUD_ICON_TEXTURE_PX`).
+const TAB_ICON_PX: f32 = 24.0;
+
+/// FiraMono glyph advance as a fraction of font size. The bar is
+/// monospace-only, so `chars × advance × font_size` is the exact label
+/// width — the same ratio `action_bar_font_size` documents.
+const FIRA_ADVANCE: f32 = 0.62;
+
+/// Gap between an icon and its revealed label, folded into the animated
+/// wrapper width so it collapses together with the text.
+const LABEL_LEAD_PX: f32 = SPACE_2;
+
+/// Idle fill of an inactive icon button — fully transparent so the pill's
+/// glass shows through untouched.
+const GLASS_BTN_IDLE: Color = Color::srgba(1.0, 1.0, 1.0, 0.0);
+/// Hover fill of an inactive icon button (desktop pointer / DPAD focus).
+const GLASS_BTN_HOVER: Color = Color::srgba(1.0, 1.0, 1.0, 0.08);
+/// Pressed fill of an inactive icon button.
+const GLASS_BTN_PRESSED: Color = Color::srgba(1.0, 1.0, 1.0, 0.14);
+/// Pressed state of the active (accent-filled) pill — darker than idle so
+/// the press reads as the surface receding, mirroring `BG_ELEVATED_PRESSED`.
+const GLASS_ACTIVE_PRESSED: Color = Color::srgb(0.55, 0.22, 0.22);
+
+/// Idle / hovered / pressed fills for one tab-bar button. Presence of this
+/// component also routes the button to `paint_glass_tab_buttons` instead of
+/// the legacy `paint_action_buttons` (which excludes it).
+#[derive(Component, Debug)]
+pub struct GlassTabButton {
+    idle: Color,
+    hovered: Color,
+    pressed: Color,
+}
+
+/// Animated label-reveal state, on the clipping wrapper node between the
+/// button and its `Text` label. `progress` ∈ [0, 1] maps to wrapper width
+/// via [`expansion_width`]; `target` is where it is heading.
+#[derive(Component, Debug)]
+pub struct TabLabelWrap {
+    /// Current reveal amount, 0 = collapsed, 1 = fully expanded.
+    pub progress: f32,
+    /// Reveal amount the animation is moving towards.
+    pub target: f32,
+    /// `true` keeps the label expanded regardless of interaction —
+    /// the persistent Draw pill, and every button in text-fallback mode.
+    persistent: bool,
+    /// Label length; width is recomputed from the live font size each
+    /// frame so viewport-driven font rescales stay correct.
+    label_chars: usize,
+    /// Last width written to the node, to skip no-op layout writes.
+    last_width: f32,
+}
+
+/// Marker on the label `Text` inside a [`TabLabelWrap`].
+#[derive(Component, Debug)]
+pub struct TabLabel;
+
+/// Duck-away state on the bar container: while a card drag is committed
+/// the whole bar slides below the screen edge so it never occludes a
+/// drop target on the bottom tableau rows, then slides back on release.
+/// `progress` ∈ [0, 1]; 1 = fully off-screen.
+#[derive(Component, Debug)]
+pub struct TabBarDuck {
+    /// Current slide amount, animated by [`duck_tab_bar_during_drag`].
+    pub progress: f32,
+}
+
+/// Extra slide distance past the bar's own height so its drop shadow
+/// (16 px blur + 6 px offset) also clears the screen edge.
+const DUCK_SHADOW_ALLOWANCE_PX: f32 = 24.0;
+
+/// Rasterised icon textures for the five tab-bar actions.
+pub(super) struct TabIcons {
+    undo: Handle<Image>,
+    draw: Handle<Image>,
+    hint: Handle<Image>,
+    pause: Handle<Image>,
+    menu: Handle<Image>,
+}
+
+impl TabIcons {
+    /// Rasterise all five icons into `images`. Returns `None` (and warns)
+    /// if any icon fails — the caller then falls back to text-only labels,
+    /// so a bad SVG degrades the look, never the playability.
+    pub(super) fn rasterize_into(images: &mut Assets<Image>) -> Option<Self> {
+        let mut add = |icon: HudIcon| match icon.rasterize() {
+            Ok(img) => Some(images.add(img)),
+            Err(e) => {
+                warn!("tab_bar: failed to rasterise {icon:?} icon: {e}");
+                None
+            }
+        };
+        Some(Self {
+            undo: add(HudIcon::Undo)?,
+            draw: add(HudIcon::Draw)?,
+            hint: add(HudIcon::Hint)?,
+            pause: add(HudIcon::Pause)?,
+            menu: add(HudIcon::Menu)?,
+        })
+    }
+}
+
+/// Wrapper width in logical px for a label of `chars` monospace glyphs at
+/// `font_size`, revealed to `progress`. Pure so the animation curve is
+/// unit-testable without an app.
+pub(super) fn expansion_width(chars: usize, font_size: f32, progress: f32) -> f32 {
+    progress.clamp(0.0, 1.0) * (LABEL_LEAD_PX + chars as f32 * font_size * FIRA_ADVANCE)
+}
+
+/// Advance `progress` towards `target` by one frame of `dt` seconds.
+/// Linear tween over `MOTION_SLIDE_SECS`, snapping when reduce-motion is
+/// active. Pure for the same reason as [`expansion_width`].
+pub(super) fn step_expansion(progress: f32, target: f32, dt: f32, reduce_motion: bool) -> f32 {
+    if reduce_motion {
+        return target;
+    }
+    let max_step = dt / crate::ui_theme::MOTION_SLIDE_SECS;
+    progress + (target - progress).clamp(-max_step, max_step)
+}
+
+/// Spawns the floating glass tab bar: one full-width invisible flex row
+/// (carrying the `HudActionBar` marker so chrome show/hide keeps working)
+/// centring the glass pill and the detached circular Menu button.
+///
+/// `icons: None` (rasteriser unavailable, e.g. `MinimalPlugins` tests, or
+/// an SVG regression) switches every button to text-fallback: labels stay
+/// expanded so the bar remains fully usable without textures.
+pub(super) fn spawn_glass_tab_bar(
+    commands: &mut Commands,
+    font: &TextFont,
+    icons: Option<&TabIcons>,
+) {
+    let text_fallback = icons.is_none();
+    commands
+        .spawn((
+            Node {
+                position_type: PositionType::Absolute,
+                bottom: Val::Px(TAB_BAR_MARGIN),
+                left: Val::Px(0.0),
+                width: Val::Percent(100.0),
+                flex_direction: FlexDirection::Row,
+                justify_content: JustifyContent::Center,
+                align_items: AlignItems::Center,
+                column_gap: VAL_SPACE_3,
+                ..default()
+            },
+            ZIndex(Z_HUD),
+            SafeAreaAnchoredBottom {
+                base_bottom: TAB_BAR_MARGIN,
+            },
+            HudActionBar,
+            TabBarDuck { progress: 0.0 },
+            UiTransform::IDENTITY,
+        ))
+        .with_children(|bar| {
+            // The main pill: Undo · [Draw] · Hint · Pause.
+            bar.spawn((
+                Node {
+                    height: Val::Px(TAB_BAR_HEIGHT),
+                    flex_direction: FlexDirection::Row,
+                    align_items: AlignItems::Center,
+                    padding: UiRect::axes(Val::Px(SPACE_2), Val::Px(0.0)),
+                    column_gap: Val::Px(4.0),
+                    border: UiRect::all(Val::Px(GLASS_BORDER_PX)),
+                    border_radius: BorderRadius::all(Val::Px(TAB_BAR_HEIGHT / 2.0)),
+                    ..default()
+                },
+                glass_surface(),
+            ))
+            .with_children(|pill| {
+                spawn_tab_button(
+                    pill,
+                    UndoButton,
+                    "Undo",
+                    "Take back your last move. Hold to keep undoing. Costs points and blocks No Undo.",
+                    font,
+                    0,
+                    icons.map(|i| i.undo.clone()),
+                    false,
+                    text_fallback,
+                );
+                spawn_tab_button(
+                    pill,
+                    DrawButton,
+                    "Draw",
+                    "Draw from the stock — same as tapping the deck.",
+                    font,
+                    1,
+                    icons.map(|i| i.draw.clone()),
+                    true,
+                    text_fallback,
+                );
+                spawn_tab_button(
+                    pill,
+                    HintButton,
+                    TOUCH_HINT_LABEL,
+                    "Highlight a suggested move. Cycles through alternatives on repeat taps.",
+                    font,
+                    2,
+                    icons.map(|i| i.hint.clone()),
+                    false,
+                    text_fallback,
+                );
+                spawn_tab_button(
+                    pill,
+                    PauseButton,
+                    "Pause",
+                    "Pause the game and freeze the timer.",
+                    font,
+                    3,
+                    icons.map(|i| i.pause.clone()),
+                    false,
+                    text_fallback,
+                );
+            });
+
+            // The detached circular Menu button, same glass material.
+            bar.spawn((
+                MenuButton,
+                ActionButton,
+                Button,
+                GlassTabButton {
+                    idle: GLASS_BTN_IDLE,
+                    hovered: GLASS_BTN_HOVER,
+                    pressed: GLASS_BTN_PRESSED,
+                },
+                Tooltip::new(
+                    "Open Home, Stats, Achievements, Profile, Settings, or Leaderboard.",
+                ),
+                Focusable {
+                    group: FocusGroup::Hud,
+                    order: 4,
+                },
+                Node {
+                    width: Val::Px(TAB_BAR_HEIGHT),
+                    height: Val::Px(TAB_BAR_HEIGHT),
+                    justify_content: JustifyContent::Center,
+                    align_items: AlignItems::Center,
+                    border: UiRect::all(Val::Px(GLASS_BORDER_PX)),
+                    border_radius: BorderRadius::all(Val::Px(TAB_BAR_HEIGHT / 2.0)),
+                    ..default()
+                },
+                BackgroundColor(GLASS_BTN_IDLE),
+                glass_surface(),
+            ))
+            .with_children(|circle| {
+                if let Some(icons) = icons {
+                    spawn_tab_icon(circle, icons.menu.clone(), TEXT_PRIMARY);
+                } else {
+                    // Text fallback: a menu glyph-free label keeps the
+                    // button discoverable without any texture.
+                    circle.spawn((
+                        Text::new("Menu"),
+                        TextLayout::new_with_linebreak(LineBreak::NoWrap),
+                        font.clone(),
+                        TextColor(TEXT_PRIMARY),
+                    ));
+                }
+            });
+        });
+}
+
+/// Spawns one button inside the pill: icon, then the width-animated label
+/// wrapper. `active` gives the accent-filled persistent pill (Draw);
+/// `text_fallback` pins every label open when icons are unavailable.
+#[allow(clippy::too_many_arguments)]
+fn spawn_tab_button<M: Component>(
+    pill: &mut ChildSpawnerCommands,
+    marker: M,
+    label: &str,
+    tooltip: &'static str,
+    font: &TextFont,
+    order: i32,
+    icon: Option<Handle<Image>>,
+    active: bool,
+    text_fallback: bool,
+) {
+    let (idle, hovered, pressed) = if active {
+        (ACCENT_PRIMARY, ACCENT_PRIMARY_HOVER, GLASS_ACTIVE_PRESSED)
+    } else {
+        (GLASS_BTN_IDLE, GLASS_BTN_HOVER, GLASS_BTN_PRESSED)
+    };
+    let icon_tint = if active { TEXT_PRIMARY } else { TEXT_SECONDARY };
+    let persistent = active || text_fallback;
+    let start = if persistent { 1.0 } else { 0.0 };
+    let chars = label.chars().count();
+
+    pill.spawn((
+        marker,
+        ActionButton,
+        Button,
+        GlassTabButton {
+            idle,
+            hovered,
+            pressed,
+        },
+        Tooltip::new(tooltip),
+        Focusable {
+            group: FocusGroup::Hud,
+            order,
+        },
+        Node {
+            height: Val::Px(TAB_BUTTON_SIZE),
+            min_width: Val::Px(TAB_BUTTON_SIZE),
+            flex_direction: FlexDirection::Row,
+            justify_content: JustifyContent::Center,
+            align_items: AlignItems::Center,
+            padding: UiRect::axes(Val::Px(SPACE_3), Val::Px(0.0)),
+            border_radius: BorderRadius::all(Val::Px(TAB_BUTTON_SIZE / 2.0)),
+            ..default()
+        },
+        BackgroundColor(idle),
+    ))
+    .with_children(|b| {
+        if let Some(handle) = icon {
+            spawn_tab_icon(b, handle, icon_tint);
+        }
+        // The clipping wrapper the animation drives. Label text sits
+        // left-anchored inside, so growing the width reveals it
+        // left-to-right and shrinking clips it from the right.
+        b.spawn((
+            TabLabelWrap {
+                progress: start,
+                target: start,
+                persistent,
+                label_chars: chars,
+                last_width: f32::NAN,
+            },
+            Node {
+                overflow: Overflow::clip(),
+                width: Val::Px(expansion_width(chars, font.font_size, start)),
+                height: Val::Percent(100.0),
+                align_items: AlignItems::Center,
+                justify_content: JustifyContent::FlexEnd,
+                ..default()
+            },
+        ))
+        .with_children(|wrap| {
+            let mut color = TEXT_PRIMARY;
+            color.set_alpha(start);
+            wrap.spawn((
+                TabLabel,
+                ActionButtonLabel,
+                Text::new(label),
+                TextLayout::new_with_linebreak(LineBreak::NoWrap),
+                font.clone(),
+                TextColor(color),
+            ));
+        });
+    });
+}
+
+/// One fixed-size tinted icon node.
+fn spawn_tab_icon(parent: &mut ChildSpawnerCommands, handle: Handle<Image>, tint: Color) {
+    parent.spawn((
+        ImageNode {
+            color: tint,
+            ..ImageNode::new(handle)
+        },
+        Node {
+            width: Val::Px(TAB_ICON_PX),
+            height: Val::Px(TAB_ICON_PX),
+            flex_shrink: 0.0,
+            ..default()
+        },
+    ));
+}
+
+/// Sets each label wrapper's animation target from its button's
+/// interaction state: persistent wrappers pin to 1, the rest expand while
+/// pressed or hovered and collapse on release.
+pub(super) fn drive_tab_expansion(
+    buttons: Query<(&Interaction, &Children), With<GlassTabButton>>,
+    mut wraps: Query<&mut TabLabelWrap>,
+) {
+    for (interaction, children) in &buttons {
+        for child in children.iter() {
+            let Ok(mut wrap) = wraps.get_mut(child) else {
+                continue;
+            };
+            let target = if wrap.persistent || !matches!(interaction, Interaction::None) {
+                1.0
+            } else {
+                0.0
+            };
+            // Bypass change detection on no-ops so `animate_tab_expansion`
+            // and layout stay idle while nothing moves.
+            if wrap.target != target {
+                wrap.target = target;
+            }
+        }
+    }
+}
+
+/// Advances every label reveal towards its target and writes the wrapper
+/// width + label alpha. Width is derived from the label's *live* font size,
+/// so the Fold's posture-change font rescale re-widens expanded labels
+/// automatically. Node writes are skipped when the width is unchanged to
+/// avoid dirtying UI layout every frame.
+pub(super) fn animate_tab_expansion(
+    time: Res<Time>,
+    settings: Option<Res<SettingsResource>>,
+    mut wraps: Query<(&mut TabLabelWrap, &mut Node, &Children)>,
+    mut labels: Query<(&TextFont, &mut TextColor), With<TabLabel>>,
+) {
+    let reduce_motion = settings.as_deref().is_some_and(|s| s.0.reduce_motion_mode);
+    let dt = time.delta_secs();
+    for (mut wrap, mut node, children) in &mut wraps {
+        for child in children.iter() {
+            let Ok((font, mut text_color)) = labels.get_mut(child) else {
+                continue;
+            };
+            let next = step_expansion(wrap.progress, wrap.target, dt, reduce_motion);
+            let width = expansion_width(wrap.label_chars, font.font_size, next);
+            // `!=` (not epsilon) is deliberate: last_width starts NaN so the
+            // first frame always writes, and equal floats mean a true no-op.
+            if next != wrap.progress || width != wrap.last_width {
+                wrap.progress = next;
+                wrap.last_width = width;
+                node.width = Val::Px(width);
+                text_color.0.set_alpha(next);
+            }
+            break;
+        }
+    }
+}
+
+/// Slides the bar off the bottom edge while a card drag is committed and
+/// back once it ends. Effectively touch-only: the desktop docked bar
+/// never carries [`TabBarDuck`], so the query is empty there.
+///
+/// The slide animates `UiTransform::translation` (a render-time offset,
+/// +y = down) rather than `Node::bottom`, for two reasons: layout is
+/// never dirtied mid-drag (the whole point is not to cost frames while
+/// the player is dragging), and `Node::bottom` is owned by the safe-area
+/// anchor system — two writers on one field would fight.
+pub(super) fn duck_tab_bar_during_drag(
+    time: Res<Time>,
+    settings: Option<Res<SettingsResource>>,
+    drag: Option<Res<DragState>>,
+    insets: Option<Res<SafeAreaInsets>>,
+    windows: Query<&Window>,
+    mut bars: Query<(&mut TabBarDuck, &mut UiTransform), With<HudActionBar>>,
+) {
+    let target = if drag.as_deref().is_some_and(|d| d.committed) {
+        1.0
+    } else {
+        0.0
+    };
+    let reduce_motion = settings.as_deref().is_some_and(|s| s.0.reduce_motion_mode);
+    let dt = time.delta_secs();
+    // Physical-px inset → logical, same conversion the safe-area anchors
+    // apply (CLAUDE.md §10): the bar sits `inset` above its base position,
+    // so the slide must cover that extra travel to fully clear the edge.
+    let scale = windows.iter().next().map_or(1.0, |w| w.scale_factor());
+    let inset_logical = insets.as_deref().map_or(0.0, |i| i.bottom / scale);
+    let slide_px = TAB_BAR_CLEARANCE_PX + inset_logical + DUCK_SHADOW_ALLOWANCE_PX;
+    for (mut duck, mut transform) in &mut bars {
+        let next = step_expansion(duck.progress, target, dt, reduce_motion);
+        if next == duck.progress && duck.progress == target {
+            continue;
+        }
+        duck.progress = next;
+        transform.translation = Val2::px(0.0, next * slide_px);
+    }
+}
+
+/// Idle / hover / pressed feedback for glass tab buttons — the glass
+/// counterpart of `paint_action_buttons`, using each button's own colour
+/// triple so the accent-filled active pill and the transparent icon
+/// buttons share one system.
+pub(super) fn paint_glass_tab_buttons(
+    mut buttons: Query<(&Interaction, &GlassTabButton, &mut BackgroundColor), Changed<Interaction>>,
+) {
+    for (interaction, style, mut bg) in &mut buttons {
+        bg.0 = match interaction {
+            Interaction::Pressed => style.pressed,
+            Interaction::Hovered => style.hovered,
+            Interaction::None => style.idle,
+        };
+    }
+}

solitaire_engine/src/hud_plugin/tests.rs

@@ -907,6 +907,10 @@ fn hud_focus_only_engages_when_button_hovered() {
 /// Bare app (no `HudPlugin`) so bar-content assertions count only the
 /// buttons the tested spawn function creates — `headless_app` would
 /// pre-spawn the platform-default bar and pollute the counts.
+///
+/// The touch branch spawns the glass tab bar with `icons: None`
+/// (`MinimalPlugins` has no `Assets<Image>`), which exercises the
+/// text-fallback path — same markers, labels pinned expanded.
 fn bar_only_app(touch: bool) -> App {
     let mut app = App::new();
     app.add_plugins(MinimalPlugins);
@@ -914,13 +918,13 @@ fn bar_only_app(touch: bool) -> App {
     let font = TextFont::default();
     let world = app.world_mut();
     let mut commands = world.commands();
-    commands.spawn(Node::default()).with_children(|row| {
     if touch {
-            spawn_touch_action_bar(row, &font);
+        spawn_glass_tab_bar(&mut commands, &font, None);
     } else {
+        commands.spawn(Node::default()).with_children(|row| {
             spawn_desktop_action_bar(row, &font);
-        }
         });
+    }
     app.update();
     app
 }
@@ -933,7 +937,7 @@ fn count_buttons<C: Component>(app: &mut App) -> usize {
 }
 
 #[test]
-fn touch_action_bar_has_thumb_trio_plus_menu_and_pause() {
+fn touch_tab_bar_has_thumb_trio_plus_menu_and_pause() {
     let mut app = bar_only_app(true);
 
     assert_eq!(count_buttons::<UndoButton>(&mut app), 1);
@@ -949,6 +953,130 @@ fn touch_action_bar_has_thumb_trio_plus_menu_and_pause() {
     assert_eq!(count_buttons::<NewGameButton>(&mut app), 0);
 }
 
+/// The glass bar floats: its container must carry a bottom margin (not be
+/// docked at 0) both before and after safe-area insets arrive.
+#[test]
+fn glass_tab_bar_floats_above_bottom_edge() {
+    let mut app = bar_only_app(true);
+    let world = app.world_mut();
+    let mut q = world.query_filtered::<(&Node, &SafeAreaAnchoredBottom), With<HudActionBar>>();
+    let (node, anchor) = q.single(world).expect("glass bar container exists");
+    assert!(anchor.base_bottom > 0.0, "bar must float, not dock");
+    assert_eq!(node.bottom, Val::Px(anchor.base_bottom));
+}
+
+/// Draw is the persistently-expanded active pill (user decision
+/// 2026-07-15); with `icons: None` every wrapper is pinned expanded via
+/// text fallback, so instead assert on the *persistent* flag's effect:
+/// all wrappers spawn at full reveal and target full reveal.
+#[test]
+fn glass_tab_bar_text_fallback_pins_labels_expanded() {
+    let mut app = bar_only_app(true);
+    let world = app.world_mut();
+    let mut q = world.query::<&TabLabelWrap>();
+    let wraps: Vec<_> = q.iter(world).collect();
+    assert_eq!(wraps.len(), 4, "Undo/Draw/Hint/Pause each carry a wrapper");
+    for wrap in wraps {
+        assert_eq!(wrap.progress, 1.0);
+        assert_eq!(wrap.target, 1.0);
+    }
+}
+
+/// Focus order must match visual reading order: pill buttons left to
+/// right, then the detached Menu circle.
+#[test]
+fn glass_tab_bar_focus_order_reads_left_to_right() {
+    let mut app = bar_only_app(true);
+
+    for (f, expected) in [
+        (focusable_for::<UndoButton>(&mut app), 0),
+        (focusable_for::<DrawButton>(&mut app), 1),
+        (focusable_for::<HintButton>(&mut app), 2),
+        (focusable_for::<PauseButton>(&mut app), 3),
+        (focusable_for::<MenuButton>(&mut app), 4),
+    ] {
+        assert_eq!(f.group, FocusGroup::Hud);
+        assert_eq!(f.order, expected);
+    }
+}
+
+/// `expansion_width` is the single source of truth for the label reveal:
+/// zero when collapsed, lead + monospace advance when expanded, linear
+/// in between.
+#[test]
+fn expansion_width_is_linear_in_progress() {
+    assert_eq!(expansion_width(4, 16.0, 0.0), 0.0);
+    let full = expansion_width(4, 16.0, 1.0);
+    assert!(full > 4.0 * 16.0 * 0.62, "full width includes the lead gap");
+    let half = expansion_width(4, 16.0, 0.5);
+    assert!((half - full / 2.0).abs() < f32::EPSILON * 100.0);
+    // Out-of-range progress clamps rather than extrapolating.
+    assert_eq!(expansion_width(4, 16.0, 1.5), full);
+}
+
+/// While a committed drag is active the bar must slide down (positive
+/// `UiTransform` y — off-screen) and return to identity once the drag
+/// ends. Manual time steps make the tween deterministic.
+#[test]
+fn tab_bar_ducks_during_committed_drag_and_returns() {
+    use crate::resources::DragState;
+    use bevy::ui::UiTransform;
+
+    let mut app = bar_only_app(true);
+    set_manual_time_step(&mut app, 0.05);
+    app.add_systems(Update, duck_tab_bar_during_drag);
+    app.insert_resource(DragState {
+        committed: true,
+        ..default()
+    });
+
+    let translation_y_px = |app: &mut App| -> f32 {
+        let world = app.world_mut();
+        let mut q = world.query_filtered::<&UiTransform, With<HudActionBar>>();
+        let t = q.single(world).expect("bar carries UiTransform");
+        match t.translation.y {
+            Val::Px(px) => px,
+            other => panic!("duck must write Val::Px, got {other:?}"),
+        }
+    };
+
+    // 0.18s slide at 0.05s/frame: fully ducked within 5 frames.
+    app.update();
+    app.update();
+    let mid = translation_y_px(&mut app);
+    assert!(mid > 0.0, "bar must start sliding down: {mid}");
+    for _ in 0..5 {
+        app.update();
+    }
+    let ducked = translation_y_px(&mut app);
+    assert!(
+        ducked > TAB_BAR_CLEARANCE_PX,
+        "fully ducked bar must clear its own floating footprint: {ducked}"
+    );
+
+    // Drag ends → bar slides back to identity.
+    app.world_mut().resource_mut::<DragState>().committed = false;
+    for _ in 0..8 {
+        app.update();
+    }
+    assert_eq!(translation_y_px(&mut app), 0.0);
+}
+
+/// The tween must move at the `MOTION_SLIDE_SECS` rate, never overshoot,
+/// and snap instantly under reduce-motion.
+#[test]
+fn step_expansion_tweens_and_respects_reduce_motion() {
+    // One 60 fps frame covers 1/(0.18*60) ≈ 9.3% of the reveal.
+    let one_frame = step_expansion(0.0, 1.0, 1.0 / 60.0, false);
+    assert!(one_frame > 0.0 && one_frame < 0.2);
+    // A huge dt clamps at the target instead of overshooting.
+    assert_eq!(step_expansion(0.0, 1.0, 10.0, false), 1.0);
+    // Collapse works symmetrically.
+    assert!(step_expansion(1.0, 0.0, 1.0 / 60.0, false) < 1.0);
+    // Reduce-motion snaps regardless of dt.
+    assert_eq!(step_expansion(0.0, 1.0, 0.0, true), 1.0);
+}
+
 #[test]
 fn desktop_action_bar_keeps_all_seven_and_no_draw() {
     let mut app = bar_only_app(false);

solitaire_engine/src/hud_plugin/updates.rs

@@ -573,20 +573,6 @@ pub(super) fn action_button_metrics() -> (UiRect, Val, Val) {
     }
 }
 
-/// Metrics for the touch bar's enlarged Undo / Draw / Hint trio (Phase F).
-/// 96×64 px targets — comfortably past the 44 px accessibility floor and
-/// big enough to hit one-handed without looking. Only the touch layout
-/// spawns primary buttons, so no desktop branch is needed; the desktop
-/// values exist purely so host-side tests can exercise the touch spawn
-/// path with sensible numbers.
-pub(super) fn primary_action_button_metrics() -> (UiRect, Val, Val) {
-    (
-        UiRect::axes(Val::Px(10.0), Val::Px(8.0)),
-        Val::Px(96.0),
-        Val::Px(64.0),
-    )
-}
-
 pub(super) fn spawn_action_button_label(
     parent: &mut ChildSpawnerCommands,
     label: &str,

solitaire_engine/src/input_plugin/mod.rs

@@ -58,6 +58,14 @@ use crate::touch_selection_plugin::TouchSelectionState;
 use crate::ui_theme::{MOTION_DRAG_REJECT_SECS, STATE_SUCCESS, STATE_WARNING};
 use solitaire_core::DrawStockConfig;
 
+/// Set wrapping the core pointer/keyboard input chain (clicks, drags, touch,
+/// hotkeys). Runs between [`crate::game_plugin::PreMutation`] (it reads the
+/// ticked game state) and [`crate::selection_plugin::SelectionKeySet`] (the
+/// selection keys check `DragState::is_idle`); request events it emits are
+/// consumed at `GameMutation` in the same frame (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PointerInput;
+
 /// System-set labels used to anchor external systems relative to the touch
 /// drag pipeline without duplicating the internal chain ordering.
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
@@ -143,7 +151,13 @@ impl Plugin for InputPlugin {
                     // `.chain()` still orders them relative to each other.
                     handle_keyboard_core
                         .in_set(crate::game_plugin::DrawRequestWriters)
-                        .ambiguous_with(crate::game_plugin::DrawRequestWriters),
+                        .ambiguous_with(crate::game_plugin::DrawRequestWriters)
+                        // N/Z/X/… and U also feed the shared new-game and
+                        // undo request streams (#143).
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                        .in_set(crate::game_plugin::UndoRequestWriters)
+                        .ambiguous_with(crate::game_plugin::UndoRequestWriters),
                     handle_keyboard_hint,
                     handle_keyboard_forfeit,
                     handle_stock_click
@@ -159,29 +173,61 @@ impl Plugin for InputPlugin {
                     end_drag.before(GameMutation),
                     // Touch drag pipeline (parallel path through DragState).
                     touch_start_drag.in_set(TouchDragSet::AfterStartDrag),
-                    touch_follow_drag,
+                    // Moves the dragged card's Transform; UiTextFx members
+                    // animate chrome entities only — disjoint domains Bevy
+                    // can't prove (#143).
+                    touch_follow_drag.ambiguous_with(crate::ui_theme::UiTextFx),
                     handle_double_tap, // before touch_end_drag: reads drag state pre-clear
                     touch_end_drag
                         .after(TouchDragSet::BeforeEndDrag)
                         .before(GameMutation),
+                    // Reads StateChangedEvent via cursor — a reset one frame
+                    // after the mutation is invisible (the cycle index only
+                    // matters on the next H press), so it rides at the end
+                    // of the input chain instead of chasing every
+                    // StateChanged writer (#143).
+                    // It also drains the new-game request stream via its own
+                    // cursor, so it joins the writer club the same way
+                    // enqueue_toasts does (#143).
+                    reset_hint_cycle_on_state_change
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
                 )
-                    .chain(),
+                    .chain()
+                    .in_set(PointerInput),
             )
-            .add_systems(Update, reset_hint_cycle_on_state_change);
+            .configure_sets(
+                Update,
+                PointerInput
+                    .after(crate::game_plugin::PreMutation)
+                    .before(crate::selection_plugin::SelectionKeySet)
+                    .before(crate::ui_focus::FocusKeys),
+            );
         // F11 fullscreen toggle is desktop-only; Android windows are always full-screen.
+        // It writes only `Window.mode`; no system reads the mode, and the
+        // geometry change it triggers arrives via WindowResized events on a
+        // later frame — order against Window readers is provably irrelevant
+        // (#143).
         #[cfg(not(target_os = "android"))]
-        app.add_systems(Update, handle_fullscreen);
+        app.add_systems(Update, handle_fullscreen.ambiguous_with_all());
         app
             // Async hint pipeline: state-change drop runs before the
             // poll system so a move applied this frame cancels any
-            // in-flight task before its result can be surfaced.
+            // in-flight task before its result can be surfaced. The poll
+            // emits the hint toast and the pile-highlight event the board
+            // painters consume this frame (#143).
             .add_systems(
                 Update,
                 (
                     crate::pending_hint::drop_pending_hint_on_state_change,
-                    crate::pending_hint::poll_pending_hint_task,
+                    crate::pending_hint::poll_pending_hint_task
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
                 )
-                    .chain(),
+                    .chain()
+                    .in_set(crate::pending_hint::PendingHint)
+                    .after(GameMutation)
+                    .before(crate::auto_complete_plugin::AutoComplete),
             );
     }
 }
@@ -215,6 +261,7 @@ fn handle_keyboard_core(
     keys: Res<ButtonInput<KeyCode>>,
     paused: Option<Res<PausedResource>>,
     progress: Option<Res<ProgressResource>>,
+    drag: Res<DragState>,
     mut ev: CoreKeyboardMessages<'_>,
     mut time_attack: Option<ResMut<TimeAttackResource>>,
     selection: Option<Res<SelectionState>>,
@@ -227,6 +274,19 @@ fn handle_keyboard_core(
         return;
     }
 
+    // Mutual exclusion with pointer drags — mirrors `handle_selection_keys`.
+    // Undo / draw / new-game during an active mouse or touch drag would fire
+    // a StateChangedEvent whose card re-sync inserts a `CardAnim` on the
+    // dragged cards, fighting `follow_drag`'s per-frame Transform writes and
+    // leaving `DragState` origin indices stale against the mutated state.
+    // The keyboard-drag sentinel may proceed: `clear_selection_on_state_change`
+    // already drops that lift cleanly when the state moves.
+    if !drag.is_idle()
+        && drag.active_touch_id != Some(crate::selection_plugin::KEYBOARD_DRAG_TOUCH_ID)
+    {
+        return;
+    }
+
     // During replay playback (Playing or Completed) all game-input shortcuts
     // are suppressed. The replay overlay owns Space (pause/resume) and the
     // arrow keys (step). Letting game input through would mutate
@@ -473,11 +533,19 @@ pub fn emit_hint_visuals(
 fn handle_keyboard_forfeit(
     keys: Res<ButtonInput<KeyCode>>,
     paused: Option<Res<PausedResource>>,
+    drag: Res<DragState>,
     mut requests: MessageWriter<ForfeitRequestEvent>,
 ) {
     if paused.is_some_and(|p| p.0) {
         return;
     }
+    // Same pointer-drag exclusion as `handle_keyboard_core` — forfeiting
+    // mid-drag would mutate the game state under the dragged cards.
+    if !drag.is_idle()
+        && drag.active_touch_id != Some(crate::selection_plugin::KEYBOARD_DRAG_TOUCH_ID)
+    {
+        return;
+    }
     if !keys.just_pressed(KeyCode::KeyG) {
         return;
     }

solitaire_engine/src/input_plugin/tests.rs

@@ -817,3 +817,123 @@ fn pressing_h_spawns_pending_hint_task() {
         "pressing H must spawn an async hint task",
     );
 }
+
+// -----------------------------------------------------------------------
+// Pointer-drag / keyboard mutual exclusion.
+//
+// A state mutation fired while `follow_drag` is writing the dragged cards'
+// transforms every frame would make the card re-sync insert a `CardAnim`
+// on the same entities (two systems fighting over `Transform`) and leave
+// `DragState`'s origin indices stale. `handle_keyboard_core` and
+// `handle_keyboard_forfeit` therefore swallow game-mutating shortcuts
+// while a mouse or touch drag is live, mirroring `handle_selection_keys`.
+// The keyboard-lift sentinel is exempt: `clear_selection_on_state_change`
+// drops that lift cleanly when the state moves.
+// -----------------------------------------------------------------------
+
+fn keyboard_core_app() -> App {
+    let mut app = App::new();
+    app.add_plugins(MinimalPlugins);
+    app.add_message::<UndoRequestEvent>();
+    app.add_message::<NewGameRequestEvent>();
+    app.add_message::<InfoToastEvent>();
+    app.add_message::<DrawRequestEvent>();
+    app.add_message::<StartZenRequestEvent>();
+    app.init_resource::<ButtonInput<KeyCode>>();
+    app.init_resource::<DragState>();
+    app.add_systems(Update, handle_keyboard_core);
+    app
+}
+
+fn press_key(app: &mut App, key: KeyCode) {
+    let mut input = app.world_mut().resource_mut::<ButtonInput<KeyCode>>();
+    input.release(key);
+    input.clear();
+    input.press(key);
+}
+
+fn message_count<M: Message>(app: &App) -> usize {
+    let messages = app.world().resource::<Messages<M>>();
+    let mut cursor = messages.get_cursor();
+    cursor.read(messages).count()
+}
+
+fn set_drag(app: &mut App, active_touch_id: Option<u64>) {
+    let mut drag = app.world_mut().resource_mut::<DragState>();
+    drag.cards = vec![Card::new(Deck::Deck1, Suit::Clubs, Rank::Two)];
+    drag.committed = true;
+    drag.active_touch_id = active_touch_id;
+}
+
+#[test]
+fn u_key_fires_undo_when_no_drag_active() {
+    let mut app = keyboard_core_app();
+    press_key(&mut app, KeyCode::KeyU);
+    app.update();
+    assert_eq!(
+        message_count::<UndoRequestEvent>(&app),
+        1,
+        "U with an idle DragState must fire UndoRequestEvent",
+    );
+}
+
+#[test]
+fn u_key_ignored_during_committed_mouse_drag() {
+    let mut app = keyboard_core_app();
+    set_drag(&mut app, None); // mouse drag
+    press_key(&mut app, KeyCode::KeyU);
+    app.update();
+    assert_eq!(
+        message_count::<UndoRequestEvent>(&app),
+        0,
+        "U during a mouse drag must be swallowed",
+    );
+}
+
+#[test]
+fn draw_key_ignored_during_touch_drag() {
+    let mut app = keyboard_core_app();
+    set_drag(&mut app, Some(7)); // real touch id
+    press_key(&mut app, KeyCode::KeyD);
+    app.update();
+    assert_eq!(
+        message_count::<DrawRequestEvent>(&app),
+        0,
+        "D during a touch drag must be swallowed",
+    );
+}
+
+#[test]
+fn u_key_allowed_during_keyboard_lift() {
+    let mut app = keyboard_core_app();
+    set_drag(
+        &mut app,
+        Some(crate::selection_plugin::KEYBOARD_DRAG_TOUCH_ID),
+    );
+    press_key(&mut app, KeyCode::KeyU);
+    app.update();
+    assert_eq!(
+        message_count::<UndoRequestEvent>(&app),
+        1,
+        "the keyboard-lift sentinel must not block core shortcuts",
+    );
+}
+
+#[test]
+fn g_key_forfeit_ignored_during_mouse_drag() {
+    let mut app = App::new();
+    app.add_plugins(MinimalPlugins);
+    app.add_message::<ForfeitRequestEvent>();
+    app.init_resource::<ButtonInput<KeyCode>>();
+    app.init_resource::<DragState>();
+    app.add_systems(Update, handle_keyboard_forfeit);
+
+    set_drag(&mut app, None);
+    press_key(&mut app, KeyCode::KeyG);
+    app.update();
+    assert_eq!(
+        message_count::<ForfeitRequestEvent>(&app),
+        0,
+        "G during a mouse drag must be swallowed",
+    );
+}

solitaire_engine/src/leaderboard_plugin.rs

@@ -24,13 +24,13 @@ use crate::font_plugin::FontResource;
 use crate::settings_plugin::{SettingsResource, SettingsStoragePath};
 use crate::sync_plugin::SyncProviderResource;
 use crate::ui_modal::{
-    ButtonVariant, ModalScrim, ScrimDismissible, spawn_modal, spawn_modal_actions,
-    spawn_modal_button, spawn_modal_header,
+    ButtonVariant, ModalScrim, ScrimDismissible, spawn_empty_state, spawn_modal,
+    spawn_modal_actions, spawn_modal_button, spawn_modal_header,
 };
 use crate::ui_theme::{
-    ACCENT_PRIMARY, BG_ELEVATED, BORDER_SUBTLE, RADIUS_SM, STATE_INFO, TEXT_DISABLED, TEXT_PRIMARY,
-    TEXT_SECONDARY, TYPE_BODY, TYPE_BODY_LG, TYPE_CAPTION, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4,
-    Z_MODAL_PANEL, Z_PAUSE_DIALOG,
+    ACCENT_PRIMARY, BG_ELEVATED, BORDER_SUBTLE, RADIUS_SM, TEXT_DISABLED, TEXT_PRIMARY,
+    TEXT_SECONDARY, TYPE_BODY, TYPE_CAPTION, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4, Z_MODAL_PANEL,
+    Z_PAUSE_DIALOG,
 };
 
 // ---------------------------------------------------------------------------
@@ -158,18 +158,38 @@ impl Plugin for LeaderboardPlugin {
                     poll_leaderboard_fetch,
                     update_leaderboard_panel,
                     handle_opt_in_button,
-                    poll_opt_in_task,
+                    // The polls share the warning-toast stream with the
+                    // daily-expiry check (drained wholesale, #143).
+                    poll_opt_in_task
+                        .in_set(crate::game_plugin::WarningToastWriters)
+                        .ambiguous_with(crate::game_plugin::WarningToastWriters),
                     handle_opt_out_button,
-                    poll_opt_out_task,
+                    poll_opt_out_task
+                        .in_set(crate::game_plugin::WarningToastWriters)
+                        .ambiguous_with(crate::game_plugin::WarningToastWriters),
                     handle_set_display_name_button,
                     handle_display_name_text_input,
                     handle_display_name_confirm,
                     handle_display_name_cancel,
-                    update_leaderboard_public_name_label,
+                    // Writes one marker-filtered Text label — disjoint from
+                    // the HUD/stats text painters (UiTextFx club, #143).
+                    update_leaderboard_public_name_label
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
                 )
-                    .chain(),
+                    .chain()
+                    // Opt-in state and display name live in
+                    // SettingsResource — the whole chain joins the
+                    // screen-plugin settings club (#143).
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess),
             )
-            .add_systems(Update, scroll_leaderboard_panel);
+            .add_systems(
+                Update,
+                scroll_leaderboard_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            );
     }
 }
 
@@ -536,11 +556,6 @@ fn spawn_leaderboard_screen(
             font_size: TYPE_CAPTION,
             ..default()
         };
-        let font_status = TextFont {
-            font: font_handle.clone(),
-            font_size: TYPE_BODY_LG,
-            ..default()
-        };
         let font_row = TextFont {
             font: font_handle.clone(),
             font_size: TYPE_BODY,
@@ -647,30 +662,31 @@ fn spawn_leaderboard_screen(
         .with_children(|body| {
             match data {
                 LeaderboardResource::Idle => {
-                    body.spawn((
-                        Text::new("Fetching\u{2026}"),
-                        font_status.clone(),
-                        TextColor(STATE_INFO),
-                    ));
+                    spawn_empty_state(
+                        body,
+                        "\u{21BB}",
+                        "Fetching the leaderboard\u{2026}",
+                        None,
+                        font_res,
+                    );
                 }
                 LeaderboardResource::Error(_) => {
-                    body.spawn((
-                        Text::new("Couldn't reach the leaderboard. Try again later."),
-                        font_status.clone(),
-                        TextColor(TEXT_SECONDARY),
-                    ));
+                    spawn_empty_state(
+                        body,
+                        "!",
+                        "Couldn't reach the leaderboard.",
+                        Some("Try again later."),
+                        font_res,
+                    );
                 }
                 LeaderboardResource::Loaded(rows) if rows.is_empty() => {
-                    body.spawn((
-                        Text::new("Be the first on the leaderboard."),
-                        font_status.clone(),
-                        TextColor(TEXT_PRIMARY),
-                    ));
-                    body.spawn((
-                        Text::new("Win a game and opt in to appear here."),
-                        font_row.clone(),
-                        TextColor(TEXT_SECONDARY),
-                    ));
+                    spawn_empty_state(
+                        body,
+                        "\u{2660}",
+                        "Be the first on the leaderboard.",
+                        Some("Win a game and opt in to appear here."),
+                        font_res,
+                    );
                 }
                 LeaderboardResource::Loaded(rows) => {
                     // Column headers

solitaire_engine/src/lib.rs

@@ -15,6 +15,8 @@ pub mod avatar_plugin;
 pub mod card_animation;
 pub mod card_plugin;
 pub mod challenge_plugin;
+pub mod cheat_sheet_plugin;
+pub mod contextual_tips_plugin;
 pub mod core_game_plugin;
 pub mod cursor_plugin;
 pub mod daily_challenge_plugin;
@@ -26,6 +28,7 @@ pub mod font_plugin;
 pub mod game_plugin;
 pub mod help_plugin;
 pub mod home_plugin;
+pub mod hotkeys;
 pub mod hud_plugin;
 pub mod input_plugin;
 pub mod layout;
@@ -60,10 +63,12 @@ pub mod theme_store_plugin;
 pub mod time_attack_plugin;
 pub mod touch_selection_plugin;
 pub mod ui_focus;
+pub mod ui_glass;
 pub mod ui_modal;
 pub mod ui_theme;
 pub mod ui_tooltip;
 pub mod weekly_goals_plugin;
+pub mod whats_new_plugin;
 pub mod win_summary_plugin;
 pub mod you_hub_plugin;
 
@@ -93,6 +98,8 @@ pub use card_plugin::{
 pub use challenge_plugin::{
     CHALLENGE_UNLOCK_LEVEL, ChallengeAdvancedEvent, ChallengePlugin, challenge_progress_label,
 };
+pub use cheat_sheet_plugin::{CheatSheetOverlay, CheatSheetPlugin};
+pub use contextual_tips_plugin::ContextualTipsPlugin;
 pub use core_game_plugin::CoreGamePlugin;
 pub use cursor_plugin::CursorPlugin;
 pub use daily_challenge_plugin::{
@@ -194,6 +201,7 @@ pub use ui_modal::{
 };
 pub use ui_tooltip::{Tooltip, UiTooltipPlugin};
 pub use weekly_goals_plugin::{WeeklyGoalCompletedEvent, WeeklyGoalsPlugin};
+pub use whats_new_plugin::{WhatsNewPending, WhatsNewPlugin, WhatsNewScreen};
 pub use win_summary_plugin::{
     ScreenShakeResource, SessionAchievements, WinSummaryPending, WinSummaryPlugin, format_win_time,
 };

solitaire_engine/src/onboarding_plugin.rs

@@ -84,66 +84,11 @@ struct OnboardingSkipButton;
 pub struct OnboardingSlideIndex(pub u8);
 
 // ---------------------------------------------------------------------------
-// Slide data — hotkey rows are taken verbatim from `help_plugin.rs` so the
-// two screens stay in sync without a shared abstraction.
+// Slide data — the hotkey slide renders the essential subset of the
+// shared table in `crate::hotkeys` (Phase J unified the previously
+// diverging copies here and in help_plugin).
 // ---------------------------------------------------------------------------
 
-/// A single `key — description` pair shown on slide 3.
-#[cfg(not(target_os = "android"))]
-struct HotkeyRow {
-    keys: &'static str,
-    description: &'static str,
-}
-
-/// Most-used shortcuts from the `help_plugin` canonical list.
-///
-/// Updating the list in `help_plugin.rs` should be mirrored here. The
-/// ARCHITECTURE.md decision log calls out that we copy values rather than
-/// refactor the help plugin.
-#[cfg(not(target_os = "android"))]
-const HOTKEYS: &[HotkeyRow] = &[
-    HotkeyRow {
-        keys: "D / Space",
-        description: "Draw from stock",
-    },
-    HotkeyRow {
-        keys: "U",
-        description: "Undo last move",
-    },
-    HotkeyRow {
-        keys: "Tab → Enter",
-        description: "Pick a card; arrows pick where; Enter to drop",
-    },
-    HotkeyRow {
-        keys: "N",
-        description: "New Classic game",
-    },
-    HotkeyRow {
-        keys: "M",
-        description: "Open Mode Launcher (then 1–5 to pick)",
-    },
-    HotkeyRow {
-        keys: "S",
-        description: "Stats & progression",
-    },
-    HotkeyRow {
-        keys: "A",
-        description: "Achievements",
-    },
-    HotkeyRow {
-        keys: "O",
-        description: "Settings",
-    },
-    HotkeyRow {
-        keys: "Esc",
-        description: "Pause / resume",
-    },
-    HotkeyRow {
-        keys: "F1",
-        description: "Help / controls",
-    },
-];
-
 // ---------------------------------------------------------------------------
 // Plugin
 // ---------------------------------------------------------------------------
@@ -153,11 +98,25 @@ pub struct OnboardingPlugin;
 
 impl Plugin for OnboardingPlugin {
     fn build(&self, app: &mut App) {
-        app.init_resource::<OnboardingSlideIndex>()
-            .add_systems(Update, spawn_if_first_run)
-            .add_systems(
+        app.init_resource::<OnboardingSlideIndex>().add_systems(
             Update,
-                (handle_onboarding_buttons, handle_onboarding_keyboard).chain(),
+            // One chain: all three touch the slide index and the
+            // first-run flag in SettingsResource. Club membership
+            // declares the settings access disjoint from the other
+            // screen plugins'; the keyboard handler runs before
+            // FocusKeys like every other Esc consumer (#143).
+            (
+                spawn_if_first_run,
+                handle_onboarding_buttons,
+                handle_onboarding_keyboard.before(crate::ui_focus::FocusKeys),
+            )
+                .chain()
+                // Before the settings spine: the first-run flag write
+                // lands before every same-frame settings reader (they
+                // all sit at or after SettingsMutation transitively).
+                .before(crate::settings_plugin::SettingsMutation)
+                .in_set(crate::settings_plugin::SettingsAccess)
+                .ambiguous_with(crate::settings_plugin::SettingsAccess),
         );
     }
 }
@@ -313,6 +272,10 @@ fn complete_onboarding(
     despawn_screen(commands, screens);
     if let Some(s) = settings {
         s.0.first_run_complete = true;
+        // A fresh install has nothing "new" to announce — stamp the
+        // running release so the What's-new card (Phase I) only ever
+        // fires after an actual upgrade.
+        s.0.last_seen_whats_new = crate::whats_new_plugin::current_release_version();
         persist(path.map(|p| &p.0), &s.0);
     }
 }
@@ -442,8 +405,10 @@ fn spawn_slide_hotkeys(commands: &mut Commands, font_res: Option<&FontResource>)
     spawn_modal(commands, OnboardingScreen, Z_ONBOARDING, |card| {
         spawn_modal_header(card, "Keyboard shortcuts", font_res);
 
-        // Vertical list of `key — description` rows, same chip style as HelpScreen.
-        for row in HOTKEYS {
+        // Vertical list of `key — description` rows, same chip style as
+        // HelpScreen. Essential subset only — the full table lives on
+        // the hold-`/` cheat sheet.
+        for row in crate::hotkeys::HOTKEYS.iter().filter(|r| r.essential) {
             card.spawn(Node {
                 flex_direction: FlexDirection::Row,
                 align_items: AlignItems::Center,
@@ -822,22 +787,15 @@ mod tests {
     }
 
     // -----------------------------------------------------------------------
-    // Hotkey list is non-empty (guards against accidental truncation)
+    // Hotkey slide renders a non-empty essential subset (the table's own
+    // integrity tests live in `crate::hotkeys`)
     // -----------------------------------------------------------------------
 
     #[test]
-    fn hotkey_list_is_non_empty() {
-        assert!(!HOTKEYS.is_empty(), "HOTKEYS must not be empty");
-    }
-
-    #[test]
-    fn all_hotkey_rows_have_non_empty_fields() {
-        for row in HOTKEYS {
-            assert!(!row.keys.is_empty(), "hotkey key field must not be empty");
+    fn hotkey_slide_subset_is_non_empty() {
         assert!(
-                !row.description.is_empty(),
-                "hotkey description must not be empty"
+            crate::hotkeys::HOTKEYS.iter().any(|r| r.essential),
+            "the onboarding slide needs at least one essential hotkey"
         );
     }
-    }
 }

solitaire_engine/src/pause_plugin.rs

@@ -104,6 +104,15 @@ pub fn draw_mode_label(mode: DrawStockConfig) -> &'static str {
 /// to disk, and routes the Forfeit confirm-modal flow.
 pub struct PausePlugin;
 
+/// Set wrapping every system that mutates [`PausedResource`] or drives the
+/// pause/forfeit modal flow. Runs as one deterministic chain between
+/// [`crate::settings_plugin::SettingsMutation`] (the pause overlay's
+/// draw-mode toggle writes `SettingsResource`) and
+/// [`crate::game_plugin::GameMutation`], so every system ordered after
+/// `GameMutation` observes this frame's pause state transitively (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PauseMutation;
+
 impl Plugin for PausePlugin {
     fn build(&self, app: &mut App) {
         // add_message is idempotent — other plugins may register these
@@ -116,28 +125,55 @@ impl Plugin for PausePlugin {
             .add_message::<crate::events::ShowSolutionRequestEvent>()
             .add_message::<InfoToastEvent>()
             .init_resource::<PausedResource>()
+            .configure_sets(
+                Update,
+                PauseMutation
+                    .after(crate::settings_plugin::SettingsMutation)
+                    // Before the pre-mutation game-state spine: the elapsed
+                    // timer must observe this frame's pause transition, and
+                    // the draw-mode toggle's settings write must land before
+                    // sync_settings_to_game forwards it.
+                    .before(crate::game_plugin::PreMutation)
+                    .before(crate::game_plugin::GameMutation)
+                    // toggle_pause must see SelectionState *before*
+                    // handle_selection_keys clears it, so it can skip Escape
+                    // when a card is selected. The other members mutate
+                    // PausedResource, which the selection keys read.
+                    .before(SelectionKeySet)
+                    // HUD buttons read PausedResource (e.g. hint is inert
+                    // while paused) — order them after this frame's pause
+                    // transition.
+                    .before(crate::hud_plugin::HudButtons),
+            )
             .add_systems(
                 Update,
                 (
-                    // toggle_pause must see SelectionState *before* handle_selection_keys
-                    // clears it, so it can skip Escape when a card is selected.
-                    // It must also run *before* handle_forfeit_keyboard so the
-                    // ForfeitConfirmScreen is still alive when toggle_pause's
-                    // early-return guard checks for it — otherwise an Esc that
-                    // closes the forfeit modal would also open pause in the
-                    // same frame.
+                    // toggle_pause must run *before* handle_forfeit_keyboard
+                    // so the ForfeitConfirmScreen is still alive when
+                    // toggle_pause's early-return guard checks for it —
+                    // otherwise an Esc that closes the forfeit modal would
+                    // also open pause in the same frame. The chain preserves
+                    // that edge and makes the whole pause/forfeit flow
+                    // deterministic (all members share PausedResource and
+                    // the forfeit message streams).
+                    // Reads only motion/display settings fields — disjoint
+                    // from the screen-plugin club's writes (#143).
                     toggle_pause
-                        .before(SelectionKeySet)
-                        .before(handle_forfeit_keyboard),
-                    handle_pause_draw_buttons,
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
+                    auto_resume_on_overlay,
+                    handle_pause_draw_buttons
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
                     handle_pause_resume_button,
                     handle_pause_forfeit_button,
                     handle_pause_solution_button,
                     handle_forfeit_request,
-                    handle_forfeit_confirm_buttons,
                     handle_forfeit_keyboard,
-                    auto_resume_on_overlay,
-                ),
+                    handle_forfeit_confirm_buttons,
+                )
+                    .chain()
+                    .in_set(PauseMutation),
             );
     }
 }

solitaire_engine/src/pending_hint.rs

@@ -39,6 +39,13 @@ use crate::resources::{GameStateResource, HintCycleIndex};
 /// emits the hint visuals once the task completes. At most one task
 /// is ever in flight: a fresh H press while a previous task is
 /// running drops the previous task and queues the new one.
+/// Set wrapping the async hint pipeline (state-change drop → poll). The
+/// HUD hint button orders `.before` it so a press cancels/spawns before
+/// this frame's poll; the drag-highlight painters order `.after` it so
+/// the hint sprite writes are settled (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PendingHint;
+
 #[derive(Resource, Default)]
 pub struct PendingHintTask {
     /// `Some` while the solver is still working on a verdict.

solitaire_engine/src/play_by_seed_plugin.rs

@@ -115,10 +115,27 @@ impl Plugin for PlayBySeedPlugin {
                 Update,
                 (
                     handle_open_dialog,
-                    handle_text_input,
-                    tick_debounce_and_spawn_solver_task,
-                    poll_solver_task,
-                    handle_confirm,
+                    // Writes the marker-filtered seed-dialog Text nodes —
+                    // disjoint from the other text painters (UiTextFx
+                    // club, #143).
+                    handle_text_input
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    tick_debounce_and_spawn_solver_task
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx)
+                        // Reads deal settings for the solver spawn; a frame
+                        // of lag is invisible (#143).
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
+                    poll_solver_task
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    // Shares the new-game request stream with the other
+                    // writers (drained wholesale at GameMutation, #143).
+                    handle_confirm
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
                     handle_cancel,
                 )
                     .chain()

solitaire_engine/src/profile_plugin.rs

@@ -60,6 +60,14 @@ pub struct DailyCalendarDot {
 /// [`spawn_profile_body`] for this tab's content.
 pub struct ProfilePlugin;
 
+/// Self-ambiguous club for writers of
+/// [`crate::events::ToggleProfileRequestEvent`] (HUD avatar button, home
+/// profile chip, HUD menu option). The You-hub reader drains the whole
+/// queue, so writer append order is irrelevant; `you_hub_plugin` orders
+/// its open/tab handling after the club (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ProfileToggleWriters;
+
 /// Marker on the scrollable body Node inside the Profile modal.
 ///
 /// The Profile panel renders sync info, progression (incl. 14-day
@@ -82,7 +90,12 @@ impl Plugin for ProfilePlugin {
             .add_message::<MouseWheel>()
             // Open/close/tab handling moved to `you_hub_plugin`
             // (Phase E) — this plugin now owns body content + scroll.
-            .add_systems(Update, scroll_profile_panel);
+            .add_systems(
+                Update,
+                scroll_profile_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            );
     }
 }
 

solitaire_engine/src/progress_plugin.rs

@@ -37,6 +37,21 @@ pub struct LevelUpEvent {
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ProgressUpdate;
 
+/// Set for `challenge_plugin::advance_on_challenge_win`. See the
+/// mode-completion chain configured in `ProgressPlugin::build` (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ChallengeCompletion;
+
+/// Set for `daily_challenge_plugin::handle_daily_completion`. See the
+/// mode-completion chain configured in `ProgressPlugin::build` (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct DailyCompletion;
+
+/// Set for `weekly_goals_plugin::evaluate_weekly_goals`. See the
+/// mode-completion chain configured in `ProgressPlugin::build` (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WeeklyGoalsEval;
+
 /// Bevy plugin that awards XP on `GameWonEvent`, persists `PlayerProgress`,
 /// and emits `LevelUpEvent` whenever a win crosses a level boundary.
 ///
@@ -74,7 +89,27 @@ impl Plugin for ProgressPlugin {
             .add_message::<GameWonEvent>()
             .add_systems(
                 Update,
-                award_xp_on_win.after(GameMutation).in_set(ProgressUpdate),
+                award_xp_on_win
+                    .after(GameMutation)
+                    .in_set(ProgressUpdate)
+                    // Base win XP lands before the mode bonuses so the
+                    // level-up attribution is stable.
+                    .before(ChallengeCompletion),
+            )
+            // Mode-completion evaluators, pinned in one explicit chain
+            // INSIDE ProgressUpdate — every `.after(ProgressUpdate)`
+            // reader then sees fully-settled progress. Each evaluator
+            // drains GameWonEvent via its own cursor and writes disjoint
+            // ProgressResource fields plus XP, but a daily win also counts
+            // toward weekly goals, so two members can fire on the same
+            // frame — we pin an order rather than argue the XP/level-up
+            // event stream is commutative (#143).
+            .configure_sets(
+                Update,
+                (ChallengeCompletion, DailyCompletion, WeeklyGoalsEval)
+                    .chain()
+                    .in_set(ProgressUpdate)
+                    .after(GameMutation),
             );
     }
 }

solitaire_engine/src/radial_menu.rs

@@ -185,16 +185,31 @@ impl Plugin for RadialMenuPlugin {
             // Tests inject `RadialCursorOverride` themselves; production
             // never touches it. We do not `init_resource` here so the
             // cursor-from-window path is the default.
+            // The radial gesture reacts to pointer state the drag pipeline
+            // settles, and its release handler feeds the shared move
+            // request stream consumed at GameMutation this frame, so the
+            // chain sits between PointerInput and GameMutation. The redraw
+            // reads settings (reduce-motion) where a frame of lag is
+            // invisible — SettingsAccess club (#143).
             .add_systems(
                 Update,
                 (
                     radial_open_on_right_click,
                     radial_open_on_long_press,
                     radial_track_cursor,
-                    radial_handle_release_or_cancel,
-                    radial_redraw_overlay,
+                    radial_handle_release_or_cancel
+                        .in_set(crate::game_plugin::MoveRequestWriters)
+                        .ambiguous_with(crate::game_plugin::MoveRequestWriters),
+                    radial_redraw_overlay
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
                 )
-                    .chain(),
+                    .chain()
+                    .after(crate::input_plugin::PointerInput)
+                    // Selection keys also touch DragState (mutual pointer/
+                    // keyboard exclusion) — keys settle first.
+                    .after(crate::selection_plugin::SelectionKeySet)
+                    .before(crate::game_plugin::GameMutation),
             );
     }
 }

solitaire_engine/src/replay_overlay/mod.rs

@@ -464,25 +464,71 @@ impl Plugin for ReplayOverlayPlugin {
                 Update,
                 (
                     react_to_state_change,
-                    update_banner_label,
-                    update_progress_text,
-                    update_floating_progress_chip,
-                    update_scrub_fill,
-                    update_move_log_header,
-                    update_move_log_active_row,
-                    update_move_log_prev_rows,
-                    update_move_log_next_rows,
-                    update_mini_tableau_foundations,
-                    update_mini_tableau_stock_waste,
-                    update_pause_button_label,
+                    // Marker-filtered Text/Node repaints — each owns one
+                    // disjoint overlay marker, so they join the UiTextFx
+                    // club alongside the HUD text painters (#143).
+                    update_banner_label
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_progress_text
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_floating_progress_chip
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_scrub_fill
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_move_log_header
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_move_log_active_row
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_move_log_prev_rows
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_move_log_next_rows
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_mini_tableau_foundations
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_mini_tableau_stock_waste
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    update_pause_button_label
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
                     handle_pause_button,
-                    handle_step_button,
+                    // Step/scrub dispatch into the shared move/draw/undo
+                    // request streams (drained wholesale at GameMutation),
+                    // so they join the writer clubs (#143).
+                    handle_step_button
+                        .in_set(crate::game_plugin::MoveRequestWriters)
+                        .ambiguous_with(crate::game_plugin::MoveRequestWriters)
+                        .in_set(crate::game_plugin::DrawRequestWriters)
+                        .ambiguous_with(crate::game_plugin::DrawRequestWriters),
                     handle_pause_keyboard,
                     handle_stop_keyboard,
-                    handle_arrow_keyboard,
+                    handle_arrow_keyboard
+                        .in_set(crate::game_plugin::MoveRequestWriters)
+                        .ambiguous_with(crate::game_plugin::MoveRequestWriters)
+                        .in_set(crate::game_plugin::UndoRequestWriters)
+                        .ambiguous_with(crate::game_plugin::UndoRequestWriters)
+                        .in_set(crate::game_plugin::DrawRequestWriters)
+                        .ambiguous_with(crate::game_plugin::DrawRequestWriters),
                     handle_stop_button,
                 )
-                    .chain(),
+                    .chain()
+                    // After the playback driver so painters render the
+                    // post-tick state; before GameMutation so the step /
+                    // scrub events are consumed this frame. Click handlers
+                    // writing ReplayPlaybackState stay at the end of the
+                    // chain — a press is observed by react_to_state_change
+                    // next frame (state-driven loop, see above) (#143).
+                    .after(crate::replay_playback::ReplayPlayback)
+                    .before(crate::game_plugin::GameMutation),
             );
     }
 }

solitaire_engine/src/replay_playback.rs

@@ -550,6 +550,14 @@ fn fire_state_changed_on_completion(
     *last_was_completed = now_completed;
 }
 
+/// Set wrapping the replay playback driver chain (tick → auto-clear →
+/// completion `StateChangedEvent`). The tick feeds `MoveRequestEvent` /
+/// `DrawRequestEvent` into this frame's [`GameMutation`], so the set sits
+/// on the pre-mutation spine; the overlay UI (`replay_overlay`) orders
+/// itself after this set so its painters render the post-tick state (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ReplayPlayback;
+
 /// Bevy plugin that initialises [`ReplayPlaybackState`] and drives
 /// playback ticks, completion linger, and the recording-pause guard.
 ///
@@ -562,18 +570,46 @@ impl Plugin for ReplayPlaybackPlugin {
     fn build(&self, app: &mut App) {
         app.init_resource::<ReplayPlaybackState>()
             .add_message::<StateChangedEvent>()
+            .configure_sets(
+                Update,
+                ReplayPlayback
+                    .after(crate::game_plugin::PreMutation)
+                    // Input first: a stop/pause press or a drag-emitted
+                    // request this frame is observed before the tick fires
+                    // the next scripted move (#143).
+                    .after(crate::input_plugin::PointerInput)
+                    .before(GameMutation),
+            )
             .add_systems(
                 Update,
                 (
-                    tick_replay_playback,
+                    // The tick shares the move/draw request streams with the
+                    // pointer/keyboard writers (drained wholesale at
+                    // GameMutation) and reads playback speed from settings.
+                    tick_replay_playback
+                        .in_set(crate::game_plugin::MoveRequestWriters)
+                        .ambiguous_with(crate::game_plugin::MoveRequestWriters)
+                        .in_set(crate::game_plugin::DrawRequestWriters)
+                        .ambiguous_with(crate::game_plugin::DrawRequestWriters)
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
                     auto_clear_completed_replay,
+                    // Chained before GameMutation: explicit order against the
+                    // mutation systems' StateChangedEvent writes; readers
+                    // drain the whole queue after GameMutation.
                     fire_state_changed_on_completion,
                 )
-                    .chain(),
+                    .chain()
+                    .in_set(ReplayPlayback),
             )
             .add_systems(
                 Update,
-                record_replay_skip_during_playback.after(GameMutation),
+                record_replay_skip_during_playback
+                    .after(GameMutation)
+                    // After AutoComplete so the stats overlay's watch-replay
+                    // handler (which resets ReplayPlaybackState) and the
+                    // win-path recorder have both settled (#143).
+                    .after(crate::auto_complete_plugin::AutoComplete),
             );
     }
 }

solitaire_engine/src/resources.rs

@@ -102,6 +102,25 @@ pub enum SyncStatus {
 #[derive(Resource, Debug, Clone, Default)]
 pub struct SyncStatusResource(pub SyncStatus);
 
+/// Outcome of the most recent successful sync merge (Phase M — sync
+/// transparency). `None` until the first pull of the session resolves.
+///
+/// The Account tab renders the conflict details; the sync poller emits a
+/// one-line toast summary when `conflicts` is non-empty.
+#[derive(Resource, Debug, Clone, Default)]
+pub struct SyncConflictLog(pub Option<SyncMergeSummary>);
+
+/// Timestamp + per-field conflict list captured from
+/// [`solitaire_sync::merge`] after a pull resolves.
+#[derive(Debug, Clone)]
+pub struct SyncMergeSummary {
+    /// When the merge resolved.
+    pub at: DateTime<Utc>,
+    /// Fields that could not be merged deterministically (best-effort
+    /// resolution already applied — see `solitaire_sync::merge`).
+    pub conflicts: Vec<solitaire_sync::ConflictReport>,
+}
+
 /// Tracks which hint the player is currently cycling through.
 ///
 /// Incremented on each H press so repeated presses reveal different moves.

solitaire_engine/src/safe_area.rs

@@ -73,11 +73,29 @@ impl Plugin for SafeAreaInsetsPlugin {
             .init_resource::<SafeAreaInsets>()
             .add_systems(
                 Update,
+                (
+                    // All three write Node padding on disjoint chrome roots
+                    // (top anchors / bottom anchors / modal scrims); chained
+                    // for a deterministic pass, and they join the UiTextFx
+                    // chrome club — anchored roots are never the label/
+                    // tooltip/readout entities the other members touch,
+                    // which Bevy can't prove from the queries (#143).
                     (
                         apply_safe_area_anchors,
                         apply_safe_area_bottom_anchors,
                         apply_safe_area_to_modal_scrims,
-                    on_app_resumed,
+                    )
+                        .chain()
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx)
+                        // UiScale is written on the settings mutator spine.
+                        .after(crate::settings_plugin::SettingsMutation),
+                    // Emits a synthetic WindowResized on resume only; every
+                    // reader drains the queue via cursor, and a resume
+                    // already spans hundreds of ms, so whether the synthetic
+                    // event lands this frame or next is invisible — same
+                    // argument as handle_fullscreen (#143).
+                    on_app_resumed.ambiguous_with_all(),
                 ),
             );
 
@@ -101,9 +119,10 @@ impl Plugin for SafeAreaInsetsPlugin {
 fn apply_safe_area_anchors(
     insets: Res<SafeAreaInsets>,
     windows: Query<&Window>,
+    ui_scale: Option<Res<UiScale>>,
     mut q: Query<(&SafeAreaAnchoredTop, &mut Node)>,
 ) {
-    if !insets.is_changed() {
+    if !insets.is_changed() && !ui_scale.as_ref().is_some_and(|s| s.is_changed()) {
         return;
     }
     // Android's WindowInsets API returns physical pixels; Bevy UI's Val::Px
@@ -119,19 +138,31 @@ fn apply_safe_area_anchors(
         );
     }
     let top_logical = raw_top.min(max_inset);
+    // `bevy::ui::UiScale` (Phase K) multiplies every Val::Px at layout
+    // time. `base_top` is UI chrome and SHOULD scale with the rest of
+    // the interface, but the system-bar inset is physical reality —
+    // pre-divide it so the post-multiplication offset stays exact.
+    let ui = effective_ui_scale(ui_scale.as_deref());
     for (anchor, mut node) in &mut q {
-        node.top = Val::Px(anchor.base_top + top_logical);
+        node.top = Val::Px(anchor.base_top + top_logical / ui);
     }
 }
 
+/// The live UI scale, defensively clamped — a zero or negative scale
+/// would flip or destroy the inset math.
+fn effective_ui_scale(ui_scale: Option<&UiScale>) -> f32 {
+    ui_scale.map_or(1.0, |s| s.0.max(0.1))
+}
+
 /// Re-applies `base_bottom + insets.bottom / scale` to every entity carrying
 /// [`SafeAreaAnchoredBottom`] whenever [`SafeAreaInsets`] changes.
 fn apply_safe_area_bottom_anchors(
     insets: Res<SafeAreaInsets>,
     windows: Query<&Window>,
+    ui_scale: Option<Res<UiScale>>,
     mut q: Query<(&SafeAreaAnchoredBottom, &mut Node)>,
 ) {
-    if !insets.is_changed() {
+    if !insets.is_changed() && !ui_scale.as_ref().is_some_and(|s| s.is_changed()) {
         return;
     }
     let scale = windows.iter().next().map_or(1.0, |w| w.scale_factor());
@@ -144,8 +175,12 @@ fn apply_safe_area_bottom_anchors(
         );
     }
     let bottom_logical = raw_bottom.min(max_inset);
+    // See `apply_safe_area_anchors`: the physical inset is pre-divided
+    // by the UI scale so a 90% setting can't sink the action bar into
+    // the gesture zone (and 130% doesn't over-inset it).
+    let ui = effective_ui_scale(ui_scale.as_deref());
     for (anchor, mut node) in &mut q {
-        node.bottom = Val::Px(anchor.base_bottom + bottom_logical);
+        node.bottom = Val::Px(anchor.base_bottom + bottom_logical / ui);
     }
 }
 
@@ -163,19 +198,23 @@ fn apply_safe_area_bottom_anchors(
 fn apply_safe_area_to_modal_scrims(
     insets: Res<SafeAreaInsets>,
     windows: Query<&Window>,
+    ui_scale: Option<Res<UiScale>>,
     mut scrims: Query<&mut Node, With<ModalScrim>>,
     new_scrims: Query<(), (With<ModalScrim>, Added<ModalScrim>)>,
 ) {
     let has_new = !new_scrims.is_empty();
-    if !insets.is_changed() && !has_new {
+    if !insets.is_changed() && !has_new && !ui_scale.as_ref().is_some_and(|s| s.is_changed()) {
         return;
     }
     let scale = windows.iter().next().map_or(1.0, |w| w.scale_factor());
     let window_height = windows.iter().next().map_or(800.0, |w| w.height());
     // Clamp each inset to 25% of screen height so an unexpectedly large OS
     // value can't push the modal card off the visible area entirely.
-    let top_logical = (insets.top / scale).min(window_height * 0.25);
-    let bottom_logical = (insets.bottom / scale).min(window_height * 0.25);
+    // Physical insets are pre-divided by the UI scale — see
+    // `apply_safe_area_anchors`.
+    let ui = effective_ui_scale(ui_scale.as_deref());
+    let top_logical = (insets.top / scale).min(window_height * 0.25) / ui;
+    let bottom_logical = (insets.bottom / scale).min(window_height * 0.25) / ui;
     for mut node in &mut scrims {
         // Set both edges so the scrim's content box equals the usable area
         // between the status bar and the gesture/navigation bar. With

solitaire_engine/src/schedule_checks.rs

@@ -23,14 +23,43 @@ mod tests {
     use bevy::ecs::schedule::{LogLevel, ScheduleBuildSettings};
     use bevy::prelude::*;
 
+    use crate::achievement_plugin::AchievementPlugin;
+    use crate::animation_plugin::AnimationPlugin;
     use crate::auto_complete_plugin::AutoCompletePlugin;
+    use crate::card_animation::CardAnimationPlugin;
     use crate::card_plugin::CardPlugin;
+    use crate::challenge_plugin::ChallengePlugin;
+    use crate::cursor_plugin::CursorPlugin;
+    use crate::daily_challenge_plugin::DailyChallengePlugin;
+    use crate::difficulty_plugin::DifficultyPlugin;
+    use crate::feedback_anim_plugin::FeedbackAnimPlugin;
     use crate::game_plugin::GamePlugin;
+    use crate::help_plugin::HelpPlugin;
+    use crate::home_plugin::HomePlugin;
     use crate::hud_plugin::HudPlugin;
+    use crate::input_plugin::InputPlugin;
+    use crate::leaderboard_plugin::LeaderboardPlugin;
+    use crate::onboarding_plugin::OnboardingPlugin;
+    use crate::pause_plugin::PausePlugin;
+    use crate::play_by_seed_plugin::PlayBySeedPlugin;
+    use crate::profile_plugin::ProfilePlugin;
+    use crate::progress_plugin::ProgressPlugin;
+    use crate::radial_menu::RadialMenuPlugin;
+    use crate::replay_overlay::ReplayOverlayPlugin;
+    use crate::replay_playback::ReplayPlaybackPlugin;
+    use crate::safe_area::SafeAreaInsetsPlugin;
+    use crate::selection_plugin::SelectionPlugin;
     use crate::settings_plugin::SettingsPlugin;
+    use crate::splash_plugin::SplashPlugin;
+    use crate::stats_plugin::StatsPlugin;
     use crate::table_plugin::TablePlugin;
+    use crate::time_attack_plugin::TimeAttackPlugin;
+    use crate::touch_selection_plugin::TouchSelectionPlugin;
     use crate::ui_focus::UiFocusPlugin;
     use crate::ui_modal::UiModalPlugin;
+    use crate::ui_tooltip::UiTooltipPlugin;
+    use crate::weekly_goals_plugin::WeeklyGoalsPlugin;
+    use crate::win_summary_plugin::WinSummaryPlugin;
 
     /// The backlog (302 pairs on 2026-07-06) was burned down to ZERO the
     /// same day (#143, PRs #146–#149) — this is now a hard gate. If your
@@ -51,7 +80,40 @@ mod tests {
             .add_plugins(AutoCompletePlugin)
             .add_plugins(UiModalPlugin)
             .add_plugins(UiFocusPlugin)
-            .add_plugins(SettingsPlugin::headless());
+            .add_plugins(SettingsPlugin::headless())
+            // Batch: game-adjacent plugins (all already exercised headless
+            // by the engine behaviour tests).
+            .add_plugins(ProgressPlugin::headless())
+            .add_plugins(StatsPlugin::headless())
+            .add_plugins(AchievementPlugin::headless())
+            .add_plugins(SelectionPlugin)
+            .add_plugins(AnimationPlugin)
+            .add_plugins(CardAnimationPlugin)
+            .add_plugins(FeedbackAnimPlugin)
+            .add_plugins(PausePlugin)
+            // Batch: screen/overlay plugins.
+            .add_plugins(HomePlugin::headless())
+            .add_plugins(WinSummaryPlugin)
+            .add_plugins(SplashPlugin)
+            .add_plugins(HelpPlugin)
+            .add_plugins(OnboardingPlugin)
+            .add_plugins(ProfilePlugin)
+            .add_plugins(LeaderboardPlugin)
+            // Batch: mode/replay/input plugins.
+            .add_plugins(ChallengePlugin)
+            .add_plugins(DailyChallengePlugin)
+            .add_plugins(TimeAttackPlugin)
+            .add_plugins(WeeklyGoalsPlugin)
+            .add_plugins(PlayBySeedPlugin)
+            .add_plugins(DifficultyPlugin)
+            .add_plugins(ReplayPlaybackPlugin)
+            .add_plugins(ReplayOverlayPlugin)
+            .add_plugins(RadialMenuPlugin)
+            .add_plugins(InputPlugin)
+            .add_plugins(TouchSelectionPlugin)
+            .add_plugins(UiTooltipPlugin)
+            .add_plugins(CursorPlugin)
+            .add_plugins(SafeAreaInsetsPlugin);
         app.init_resource::<ButtonInput<KeyCode>>();
         app
     }

solitaire_engine/src/selection_plugin.rs

@@ -134,6 +134,14 @@ impl KeyboardDragState {
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct SelectionKeySet;
 
+/// Set wrapping the post-mutation selection maintenance chain (clearing the
+/// selection on state change, painting the highlight). Runs between
+/// [`crate::game_plugin::GameMutation`] and
+/// [`crate::card_plugin::BoardVisuals`] so the painters read the settled
+/// selection/drag state (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SelectionFx;
+
 /// Marker component placed on the outline sprite used as the keyboard-selection
 /// highlight.
 ///
@@ -158,14 +166,35 @@ impl Plugin for SelectionPlugin {
                 (
                     handle_selection_keys
                         .in_set(SelectionKeySet)
-                        .before(GameMutation),
-                    clear_selection_on_state_change.after(GameMutation),
-                    update_selection_highlight.after(GameMutation).run_if(
+                        .before(GameMutation)
+                        // Enter-to-move feeds the shared move request
+                        // stream (drained wholesale at GameMutation, #143).
+                        .in_set(crate::game_plugin::MoveRequestWriters)
+                        .ambiguous_with(crate::game_plugin::MoveRequestWriters),
+                    (
+                        clear_selection_on_state_change,
+                        update_selection_highlight.run_if(
                             resource_changed::<SelectionState>
                                 .or(resource_changed::<KeyboardDragState>)
                                 .or(resource_changed::<GameStateResource>),
                         ),
+                    )
+                        .chain()
+                        .in_set(SelectionFx),
                 ),
+            )
+            .configure_sets(
+                Update,
+                SelectionFx
+                    .after(GameMutation)
+                    .before(crate::card_plugin::BoardVisuals),
+            )
+            .configure_sets(
+                Update,
+                // Selection reads GameStateResource (legal destinations) —
+                // run after the pre-mutation spine that ticks/mutates it
+                // (#143).
+                SelectionKeySet.after(crate::game_plugin::PreMutation),
             );
     }
 }

solitaire_engine/src/settings_plugin/data_transfer.rs

@@ -0,0 +1,139 @@
+//! Phase M (sync transparency): local backup export/import.
+//!
+//! Runs in the `Last` schedule — the export snapshot is taken after the
+//! whole frame settles, and the import's resource rewrites become visible
+//! to every Update system on the next frame, keeping this rare bulk
+//! operation off the annotated Update spine entirely.
+
+use bevy::prelude::*;
+use chrono::Utc;
+use solitaire_data::{DataBundle, data_bundle_path, load_bundle_from, save_bundle_to};
+
+use crate::achievement_plugin::{AchievementsResource, AchievementsStoragePath};
+use crate::events::{
+    DataExportRequestEvent, DataImportRequestEvent, InfoToastEvent, WarningToastEvent,
+};
+use crate::progress_plugin::{ProgressResource, ProgressStoragePath};
+use crate::stats_plugin::{StatsResource, StatsStoragePath};
+
+use super::{SettingsChangedEvent, SettingsResource, SettingsStoragePath};
+
+/// Drains the export/import request streams and performs the file IO.
+///
+/// The bundle is small (a few KB of JSON), so the write happens inline
+/// rather than on the async pool — one synchronous write per explicit
+/// button press, never per frame.
+#[allow(clippy::too_many_arguments)]
+pub(super) fn handle_data_transfer(
+    mut exports: MessageReader<DataExportRequestEvent>,
+    mut imports: MessageReader<DataImportRequestEvent>,
+    mut settings: ResMut<SettingsResource>,
+    settings_path: Res<SettingsStoragePath>,
+    stats: Option<ResMut<StatsResource>>,
+    stats_path: Option<Res<StatsStoragePath>>,
+    achievements: Option<ResMut<AchievementsResource>>,
+    achievements_path: Option<Res<AchievementsStoragePath>>,
+    progress: Option<ResMut<ProgressResource>>,
+    progress_path: Option<Res<ProgressStoragePath>>,
+    mut settings_changed: MessageWriter<SettingsChangedEvent>,
+    mut info_toast: MessageWriter<InfoToastEvent>,
+    mut warning_toast: MessageWriter<WarningToastEvent>,
+) {
+    let export_requested = exports.read().next().is_some();
+    let import_requested = imports.read().next().is_some();
+    if !export_requested && !import_requested {
+        return;
+    }
+    // The bundle lives next to settings.json (same app data dir in
+    // production); deriving it from the injected settings path keeps
+    // tests off the real platform directory.
+    let path = settings_path
+        .0
+        .as_ref()
+        .map(|p| p.with_file_name(solitaire_data::transfer::DATA_BUNDLE_FILE_NAME))
+        .or_else(data_bundle_path);
+    let Some(path) = path else {
+        warning_toast.write(WarningToastEvent(
+            "No data directory available on this platform".to_string(),
+        ));
+        return;
+    };
+
+    // An import in the same frame as an export would race on the file;
+    // real UI can't produce both, but be deterministic anyway: export
+    // first, then import reads what was just written (a no-op restore).
+    if export_requested {
+        let bundle = DataBundle {
+            schema_version: solitaire_data::DATA_BUNDLE_SCHEMA_VERSION,
+            exported_at: Utc::now(),
+            settings: settings.0.clone(),
+            stats: stats.as_ref().map(|s| s.0.clone()).unwrap_or_default(),
+            achievements: achievements
+                .as_ref()
+                .map(|a| a.0.clone())
+                .unwrap_or_default(),
+            progress: progress.as_ref().map(|p| p.0.clone()).unwrap_or_default(),
+        };
+        match save_bundle_to(&path, &bundle) {
+            Ok(()) => {
+                info_toast.write(InfoToastEvent(format!(
+                    "Data exported to {}",
+                    path.display()
+                )));
+            }
+            Err(e) => {
+                warn!("data export failed: {e}");
+                warning_toast.write(WarningToastEvent(format!("Export failed: {e}")));
+            }
+        }
+    }
+
+    if import_requested {
+        match load_bundle_from(&path) {
+            Ok(bundle) => {
+                settings.0 = bundle.settings;
+                if let Some(target) = &settings_path.0
+                    && let Err(e) = solitaire_data::save_settings_to(target, &settings.0)
+                {
+                    warn!("import: failed to persist settings: {e}");
+                }
+                // Settings appliers (theme, audio, layout) react to the
+                // change event exactly as if edited in the panel.
+                settings_changed.write(SettingsChangedEvent(settings.0.clone()));
+
+                if let Some(mut s) = stats {
+                    s.0 = bundle.stats;
+                    if let Some(target) = stats_path.as_ref().and_then(|p| p.0.as_ref())
+                        && let Err(e) = solitaire_data::save_stats_to(target, &s.0)
+                    {
+                        warn!("import: failed to persist stats: {e}");
+                    }
+                }
+                if let Some(mut a) = achievements {
+                    a.0 = bundle.achievements;
+                    if let Some(target) = achievements_path.as_ref().and_then(|p| p.0.as_ref())
+                        && let Err(e) = solitaire_data::save_achievements_to(target, &a.0)
+                    {
+                        warn!("import: failed to persist achievements: {e}");
+                    }
+                }
+                if let Some(mut p) = progress {
+                    p.0 = bundle.progress;
+                    if let Some(target) = progress_path.as_ref().and_then(|pp| pp.0.as_ref())
+                        && let Err(e) = solitaire_data::save_progress_to(target, &p.0)
+                    {
+                        warn!("import: failed to persist progress: {e}");
+                    }
+                }
+                info_toast.write(InfoToastEvent(format!(
+                    "Backup from {} restored",
+                    bundle.exported_at.format("%Y-%m-%d %H:%M UTC")
+                )));
+            }
+            Err(e) => {
+                warn!("data import failed: {e}");
+                warning_toast.write(WarningToastEvent(format!("Import failed: {e}")));
+            }
+        }
+    }
+}

solitaire_engine/src/settings_plugin/input.rs

@@ -353,6 +353,14 @@ pub(super) fn handle_settings_buttons(
                     **t = on_off_label(settings.0.reduce_motion_mode);
                 }
             }
+            SettingsButton::ToggleReduceTransparency => {
+                settings.0.reduce_transparency_mode = !settings.0.reduce_transparency_mode;
+                persist(&path, &settings.0);
+                changed.write(SettingsChangedEvent(settings.0.clone()));
+                // Text refreshed by `update_reduce_transparency_text`; the
+                // glass chrome itself follows via `update_glass_surfaces`
+                // next frame.
+            }
             SettingsButton::ToggleTouchInputMode => {
                 use solitaire_data::settings::TouchInputMode;
                 settings.0.touch_input_mode = match settings.0.touch_input_mode {
@@ -363,6 +371,14 @@ pub(super) fn handle_settings_buttons(
                 changed.write(SettingsChangedEvent(settings.0.clone()));
                 // Text refreshed by `update_touch_input_mode_text` next frame.
             }
+            SettingsButton::CycleUiScale => {
+                settings.0.ui_scale = next_ui_scale(settings.0.ui_scale);
+                persist(&path, &settings.0);
+                changed.write(SettingsChangedEvent(settings.0.clone()));
+                // Text refreshed by `update_ui_scale_text`; the live
+                // `bevy::ui::UiScale` resource follows via
+                // `sync_ui_scale_resource` next frame.
+            }
             SettingsButton::ToggleWinnableDealsOnly => {
                 settings.0.winnable_deals_only = !settings.0.winnable_deals_only;
                 persist(&path, &settings.0);
@@ -417,6 +433,9 @@ pub(super) fn handle_settings_buttons(
             SettingsButton::OpenThemeStore => {
                 // Handled by `handle_sync_buttons`.
             }
+            SettingsButton::ExportData | SettingsButton::ImportData => {
+                // Handled by `handle_sync_buttons`.
+            }
             SettingsButton::Done => {
                 screen.0 = false;
             }
@@ -444,14 +463,18 @@ pub(super) fn handle_tab_buttons(
 }
 
 /// Handles sync-related settings buttons: Sync Now, Connect, Disconnect,
-/// and Delete Account. Split from `handle_settings_buttons` to stay within
-/// Bevy's 16-parameter system limit.
+/// Delete Account, and the Phase M Export/Import data pair. Split from
+/// `handle_settings_buttons` to stay within Bevy's 16-parameter system
+/// limit.
+#[allow(clippy::too_many_arguments)]
 pub(super) fn handle_sync_buttons(
     interaction_query: Query<(&Interaction, &SettingsButton), Changed<Interaction>>,
     mut manual_sync: MessageWriter<ManualSyncRequestEvent>,
     mut configure_sync: MessageWriter<SyncConfigureRequestEvent>,
     mut logout_sync: MessageWriter<SyncLogoutRequestEvent>,
     mut delete_account: MessageWriter<DeleteAccountRequestEvent>,
+    mut export_data: MessageWriter<crate::events::DataExportRequestEvent>,
+    mut import_data: MessageWriter<crate::events::DataImportRequestEvent>,
     #[cfg(not(target_arch = "wasm32"))] mut open_theme_store: MessageWriter<
         crate::events::ThemeStoreOpenRequestEvent,
     >,
@@ -484,6 +507,12 @@ pub(super) fn handle_sync_buttons(
             SettingsButton::DeleteAccount => {
                 delete_account.write(DeleteAccountRequestEvent);
             }
+            SettingsButton::ExportData => {
+                export_data.write(crate::events::DataExportRequestEvent);
+            }
+            SettingsButton::ImportData => {
+                import_data.write(crate::events::DataImportRequestEvent);
+            }
             _ => {}
         }
     }

solitaire_engine/src/settings_plugin/mod.rs

@@ -25,6 +25,7 @@ use crate::events::{
 use crate::resources::SettingsScrollPos;
 use crate::theme::ThemeThumbnailPair;
 
+mod data_transfer;
 mod input;
 mod ui;
 mod updates;
@@ -87,6 +88,19 @@ pub struct SettingsChangedEvent(pub Settings);
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct SettingsMutation;
 
+/// Self-ambiguous club for the screen/overlay systems that touch
+/// [`SettingsResource`] (onboarding first-run flag, home difficulty/draw
+/// chips, leaderboard opt-in and display name, pause draw toggle, splash
+/// reduce-motion reads, …). Each accessor touches its own disjoint fields,
+/// and the modal-stacking guard means at most one of these screens is
+/// interactive at a time — same-frame access order is provably irrelevant,
+/// so members declare `.in_set(SettingsAccess).ambiguous_with(SettingsAccess)`
+/// (#143). [`SettingsMutation`] is nested inside the club (its members keep
+/// their internal chain). Do NOT add members whose settings read must be
+/// same-frame-exact; order those `.after(SettingsMutation)` instead.
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SettingsAccess;
+
 /// Marker on the root Settings panel entity.
 #[derive(Component, Debug)]
 pub struct SettingsPanel;
@@ -111,6 +125,12 @@ struct ThemeText;
 #[derive(Component, Debug)]
 struct SyncStatusText;
 
+/// Marks the headline `Text` node of the last-merge summary in the
+/// Account tab (Phase M — sync transparency). Tests query it to assert
+/// the summary rendered.
+#[derive(Component, Debug)]
+pub(super) struct SyncMergeSummaryText;
+
 /// Marks the `Text` node showing the active card-back index.
 #[derive(Component, Debug)]
 struct CardBackText;
@@ -135,10 +155,18 @@ struct HighContrastText;
 #[derive(Component, Debug)]
 struct ReduceMotionText;
 
+/// Marks the `Text` node showing the current reduce-transparency state.
+#[derive(Component, Debug)]
+struct ReduceTransparencyText;
+
 /// Marks the `Text` node showing the current touch input mode state.
 #[derive(Component, Debug)]
 struct TouchInputModeText;
 
+/// Marks the `Text` node showing the current UI scale percentage.
+#[derive(Component, Debug)]
+struct UiScaleText;
+
 /// Marks the `Text` node showing the live tooltip-delay value.
 #[derive(Component, Debug)]
 struct TooltipDelayText;
@@ -273,10 +301,18 @@ enum SettingsButton {
     /// non-essential motion (card-slide animations become instant
     /// snaps) per `design-system.md` §Accessibility (#3).
     ToggleReduceMotion,
+    /// Toggle the [`Settings::reduce_transparency_mode`] flag — swaps
+    /// translucent glass chrome (the floating touch tab bar) for opaque
+    /// fills so table content never bleeds through UI text.
+    ToggleReduceTransparency,
     /// Toggle [`Settings::touch_input_mode`] between `OneTap`
     /// (auto-move on tap, default) and `TapToSelect` (first tap selects
     /// a card/stack, second tap on a target pile moves it).
     ToggleTouchInputMode,
+    /// Cycle [`Settings::ui_scale`] through 90 % → 100 % → 115 % →
+    /// 130 % → 90 %. Applied live via `bevy::ui::UiScale`; the table
+    /// stays window-fit (Phase K).
+    CycleUiScale,
     /// Toggle the [`Settings::winnable_deals_only`] flag. When on, new
     /// random Classic-mode deals are filtered through
     /// [`solitaire_core::game_state::GameState::solve_fresh_deal`] until one is provably
@@ -305,6 +341,10 @@ enum SettingsButton {
     DisconnectSync,
     /// Open the account-deletion confirmation modal.
     DeleteAccount,
+    /// Write every JSON save into one backup bundle (Phase M).
+    ExportData,
+    /// Restore every JSON save from the backup bundle (Phase M).
+    ImportData,
     Done,
     /// Select a specific card-back by index from the picker row.
     SelectCardBack(usize),
@@ -353,7 +393,9 @@ impl SettingsButton {
             // run before continuing to the picker rows.
             SettingsButton::ToggleHighContrast => 61,
             SettingsButton::ToggleReduceMotion => 62,
-            SettingsButton::ToggleTouchInputMode => 63,
+            SettingsButton::ToggleReduceTransparency => 63,
+            SettingsButton::ToggleTouchInputMode => 64,
+            SettingsButton::CycleUiScale => 65,
             // Picker rows — every swatch in a row shares the row's
             // priority so entity-index tiebreaking yields left → right.
             SettingsButton::SelectCardBack(_) => 70,
@@ -368,6 +410,8 @@ impl SettingsButton {
             SettingsButton::ConnectSync => 91,
             SettingsButton::DisconnectSync => 92,
             SettingsButton::DeleteAccount => 93,
+            SettingsButton::ExportData => 94,
+            SettingsButton::ImportData => 95,
             // Done is tagged by `attach_focusable_to_modal_buttons` and
             // never reaches `attach_focusable_to_settings_buttons`; the
             // value here is only a fallback for completeness.
@@ -421,6 +465,15 @@ impl Plugin for SettingsPlugin {
             .add_message::<SyncConfigureRequestEvent>()
             .add_message::<SyncLogoutRequestEvent>()
             .add_message::<DeleteAccountRequestEvent>()
+            .add_message::<crate::events::DataExportRequestEvent>()
+            .add_message::<crate::events::DataImportRequestEvent>()
+            // Idempotent — the sync plugin also registers it; needed here
+            // so the transfer handler's failure toasts work headless.
+            .add_message::<crate::events::WarningToastEvent>()
+            // Bulk backup/restore lives in Last: the export snapshot is
+            // taken post-frame and an import's rewrites surface next
+            // frame — keeps the rare path off the annotated Update spine.
+            .add_systems(Last, data_transfer::handle_data_transfer)
             .add_message::<ToggleSettingsRequestEvent>()
             .add_message::<crate::events::ThemeStoreOpenRequestEvent>()
             .add_message::<InfoToastEvent>()
@@ -441,7 +494,12 @@ impl Plugin for SettingsPlugin {
                 Update,
                 SettingsMutation
                     .after(crate::layout::LayoutSystem::UpdateOnResize)
-                    .before(crate::game_plugin::GameMutation),
+                    .before(crate::game_plugin::GameMutation)
+                    // Nested in the club: members keep their chain, but
+                    // their pairs against other screen-plugin settings
+                    // accessors are declared irrelevant (#143).
+                    .in_set(SettingsAccess)
+                    .ambiguous_with(SettingsAccess),
             )
             .add_systems(
                 Update,
@@ -449,6 +507,11 @@ impl Plugin for SettingsPlugin {
                     handle_volume_keys,
                     record_window_geometry_changes,
                     persist_window_geometry_after_debounce,
+                    // State sync, not UI — runs even under `headless()`
+                    // so the live `bevy::ui::UiScale` always mirrors the
+                    // setting; rides the mutator spine so it is ordered
+                    // after every settings writer this frame.
+                    sync_ui_scale_resource,
                 )
                     .chain()
                     .in_set(SettingsMutation),
@@ -459,8 +522,12 @@ impl Plugin for SettingsPlugin {
                     toggle_settings_screen
                         .before(crate::ui_focus::FocusKeys)
                         .ambiguous_with(crate::hud_plugin::HudButtons),
-                    scroll_settings_panel,
-                    crate::ui_modal::touch_scroll_panel::<SettingsPanelScrollable>,
+                    scroll_settings_panel
+                        .in_set(crate::ui_modal::PanelScroll)
+                        .ambiguous_with(crate::ui_modal::PanelScroll),
+                    crate::ui_modal::touch_scroll_panel::<SettingsPanelScrollable>
+                        .in_set(crate::ui_modal::PanelScroll)
+                        .ambiguous_with(crate::ui_modal::PanelScroll),
                 )
                     .chain(),
             );
@@ -492,6 +559,7 @@ impl Plugin for SettingsPlugin {
                     update_high_contrast_backgrounds.run_if(resource_changed::<SettingsResource>),
                     update_reduce_motion_text,
                     update_touch_input_mode_text,
+                    update_ui_scale_text,
                     update_tooltip_delay_text,
                     update_time_bonus_multiplier_text,
                     update_replay_move_interval_text,
@@ -499,6 +567,16 @@ impl Plugin for SettingsPlugin {
                     update_smart_default_size_text,
                 ),
             );
+            app.add_systems(
+                Update,
+                (
+                    update_reduce_transparency_text,
+                    // Guards internally on settings-change / newly added
+                    // glass — `Added<GlassSurface>` can't be expressed as
+                    // a resource run condition.
+                    update_glass_surfaces,
+                ),
+            );
             app.add_systems(
                 Update,
                 (

solitaire_engine/src/settings_plugin/tests.rs

@@ -736,3 +736,150 @@ fn scroll_clamps_offset_to_zero_at_top() {
         "scrolling past top must clamp to 0, got {offset}"
     );
 }
+
+// ---------------------------------------------------------------------------
+// Phase K: UI scale
+// ---------------------------------------------------------------------------
+
+#[test]
+fn ui_scale_steps_cycle_and_wrap() {
+    assert_eq!(next_ui_scale(0.9), 1.0);
+    assert_eq!(next_ui_scale(1.0), 1.15);
+    assert_eq!(next_ui_scale(1.15), 1.3);
+    assert_eq!(next_ui_scale(1.3), 0.9, "the cycle must wrap");
+    // A hand-edited in-between value advances to the next larger step.
+    assert_eq!(next_ui_scale(1.05), 1.15);
+}
+
+#[test]
+fn ui_scale_label_formats_as_percent() {
+    assert_eq!(ui_scale_label(0.9), "90%");
+    assert_eq!(ui_scale_label(1.0), "100%");
+    assert_eq!(ui_scale_label(1.15), "115%");
+    assert_eq!(ui_scale_label(1.3), "130%");
+}
+
+#[test]
+fn ui_scale_setting_syncs_the_bevy_resource() {
+    let mut app = headless_app();
+    app.insert_resource(UiScale(1.0));
+    app.world_mut()
+        .resource_mut::<SettingsResource>()
+        .0
+        .ui_scale = 1.3;
+    app.update();
+
+    assert!(
+        (app.world().resource::<UiScale>().0 - 1.3).abs() < f32::EPSILON,
+        "Settings::ui_scale must drive bevy::ui::UiScale"
+    );
+}
+
+#[test]
+fn ui_scale_out_of_range_sanitizes_on_load() {
+    use solitaire_data::settings::{UI_SCALE_MAX, UI_SCALE_MIN};
+
+    let wild = Settings {
+        ui_scale: 5.0,
+        ..Settings::default()
+    }
+    .sanitized();
+    assert_eq!(wild.ui_scale, UI_SCALE_MAX);
+
+    let tiny = Settings {
+        ui_scale: 0.1,
+        ..Settings::default()
+    }
+    .sanitized();
+    assert_eq!(tiny.ui_scale, UI_SCALE_MIN);
+}
+
+// ---------------------------------------------------------------------------
+// Phase M: local data export / import
+// ---------------------------------------------------------------------------
+
+/// App with a real (temp-dir) settings path so the data-transfer handler
+/// derives its bundle path inside the temp dir instead of the platform
+/// data directory.
+fn transfer_app(dir: &std::path::Path) -> App {
+    let mut app = App::new();
+    app.add_plugins(MinimalPlugins).add_plugins(SettingsPlugin {
+        storage_path: Some(dir.join("settings.json")),
+        ui_enabled: false,
+    });
+    app.init_resource::<ButtonInput<KeyCode>>();
+    app.update();
+    app
+}
+
+#[test]
+fn export_then_import_round_trips_settings() {
+    let dir = std::env::temp_dir().join(format!("settings_transfer_{}", std::process::id()));
+    std::fs::create_dir_all(&dir).expect("temp dir");
+    let mut app = transfer_app(&dir);
+
+    app.world_mut()
+        .resource_mut::<SettingsResource>()
+        .0
+        .sfx_volume = 0.25;
+    app.world_mut()
+        .write_message(crate::events::DataExportRequestEvent);
+    app.update();
+    assert!(
+        dir.join(solitaire_data::transfer::DATA_BUNDLE_FILE_NAME)
+            .exists(),
+        "export should write the bundle next to settings.json"
+    );
+
+    // Clobber the live value, then restore from the bundle.
+    app.world_mut()
+        .resource_mut::<SettingsResource>()
+        .0
+        .sfx_volume = 1.0;
+    app.world_mut()
+        .write_message(crate::events::DataImportRequestEvent);
+    app.update();
+    // Import handling runs in Last of the same frame; the rewrite is
+    // visible immediately after update() returns.
+    let restored = app.world().resource::<SettingsResource>().0.sfx_volume;
+    assert!(
+        (restored - 0.25).abs() < f32::EPSILON,
+        "import should restore the exported value, got {restored}"
+    );
+
+    let _ = std::fs::remove_dir_all(&dir);
+}
+
+#[test]
+fn import_without_backup_warns_instead_of_defaulting() {
+    let dir =
+        std::env::temp_dir().join(format!("settings_transfer_missing_{}", std::process::id()));
+    std::fs::create_dir_all(&dir).expect("temp dir");
+    let mut app = transfer_app(&dir);
+
+    app.world_mut()
+        .resource_mut::<SettingsResource>()
+        .0
+        .sfx_volume = 0.25;
+    app.world_mut()
+        .write_message(crate::events::DataImportRequestEvent);
+    app.update();
+
+    // Settings untouched (no silent default-restore)…
+    let v = app.world().resource::<SettingsResource>().0.sfx_volume;
+    assert!(
+        (v - 0.25).abs() < f32::EPSILON,
+        "failed import must not touch settings"
+    );
+    // …and the failure is surfaced as a warning toast.
+    let msgs = app
+        .world()
+        .resource::<Messages<crate::events::WarningToastEvent>>();
+    let mut cursor = msgs.get_cursor();
+    assert!(
+        cursor.read(msgs).any(|w| w.0.contains("Import failed")),
+        "missing backup should emit a warning toast"
+    );
+
+    let _ = std::fs::remove_dir_all(&dir);
+}

solitaire_engine/src/settings_plugin/ui.rs

@@ -46,6 +46,7 @@ pub(super) fn spawn_settings_panel(
     scroll_offset: f32,
     font_res: Option<&FontResource>,
     theme_overrides_back: bool,
+    conflict_log: Option<&crate::resources::SyncConflictLog>,
     active_tab: SettingsTab,
 ) {
     spawn_modal(commands, SettingsPanel, Z_MODAL_PANEL, |card| {
@@ -100,7 +101,9 @@ pub(super) fn spawn_settings_panel(
                 font_res,
             ),
             SettingsTab::Accessibility => spawn_accessibility_tab(body, settings, font_res),
-            SettingsTab::Account => spawn_account_tab(body, settings, sync_status, font_res),
+            SettingsTab::Account => {
+                spawn_account_tab(body, settings, sync_status, conflict_log, font_res)
+            }
         });
 
         // Done is the only action — primary so the player always knows
@@ -317,6 +320,15 @@ fn spawn_accessibility_tab(
         "Skips card-slide animations and other non-essential motion. Cards snap instantly to their target.",
         font_res,
     );
+    toggle_row(
+        body,
+        "Reduce Transparency",
+        ReduceTransparencyText,
+        on_off_label(settings.reduce_transparency_mode),
+        SettingsButton::ToggleReduceTransparency,
+        "Replaces the see-through glass toolbar with a solid panel so cards behind it never reduce readability.",
+        font_res,
+    );
     toggle_row(
         body,
         "Touch Input Mode",
@@ -326,6 +338,15 @@ fn spawn_accessibility_tab(
         "One-tap: tap a card to auto-move it. Tap to select: first tap selects a card, second tap on a pile moves it.",
         font_res,
     );
+    toggle_row(
+        body,
+        "UI Scale",
+        UiScaleText,
+        ui_scale_label(settings.ui_scale),
+        SettingsButton::CycleUiScale,
+        "Scales all menus, buttons, and HUD text. The table itself always fits the screen.",
+        font_res,
+    );
     tooltip_delay_row(body, settings.tooltip_delay_secs, font_res);
 }
 
@@ -335,6 +356,7 @@ fn spawn_account_tab(
     body: &mut ChildSpawnerCommands,
     settings: &Settings,
     sync_status: &str,
+    conflict_log: Option<&crate::resources::SyncConflictLog>,
     font_res: Option<&FontResource>,
 ) {
     // --- Privacy (only shown when a Matomo URL is configured) ---
@@ -354,6 +376,144 @@ fn spawn_account_tab(
     // --- Sync ---
     section_label(body, "Sync", font_res);
     sync_row(body, sync_status, &settings.sync_backend, font_res);
+    spawn_sync_merge_summary(body, conflict_log, font_res);
+
+    // --- Local data (Phase M) --- backup/restore of the JSON saves;
+    // filesystem-backed, so not offered on the wasm build.
+    #[cfg(not(target_arch = "wasm32"))]
+    {
+        section_label(body, "Local data", font_res);
+        local_data_row(body, font_res);
+    }
+}
+
+/// `Export data` / `Import data` pill buttons plus a caption naming the
+/// backup file (Phase M). Mirrors the sync row's pill-button styling.
+#[cfg(not(target_arch = "wasm32"))]
+fn local_data_row(parent: &mut ChildSpawnerCommands, font_res: Option<&FontResource>) {
+    let button_font = TextFont {
+        font: font_res.map(|f| f.0.clone()).unwrap_or_default(),
+        font_size: TYPE_CAPTION,
+        ..default()
+    };
+    let caption_font = button_font.clone();
+
+    let small_button = |row: &mut ChildSpawnerCommands,
+                        marker: SettingsButton,
+                        label: &str,
+                        tooltip: String,
+                        font: TextFont| {
+        row.spawn((
+            marker,
+            Button,
+            Tooltip::new(tooltip),
+            Node {
+                padding: UiRect::axes(VAL_SPACE_3, VAL_SPACE_2),
+                justify_content: JustifyContent::Center,
+                border: UiRect::all(Val::Px(1.0)),
+                border_radius: BorderRadius::all(Val::Px(RADIUS_SM)),
+                ..default()
+            },
+            BackgroundColor(BG_ELEVATED_HI),
+            BorderColor::all(BORDER_SUBTLE),
+            HighContrastBorder::with_default(BORDER_SUBTLE),
+        ))
+        .with_children(|b| {
+            b.spawn((Text::new(label.to_string()), font, TextColor(TEXT_PRIMARY)));
+        });
+    };
+
+    parent
+        .spawn(Node {
+            flex_direction: FlexDirection::Column,
+            row_gap: VAL_SPACE_2,
+            ..default()
+        })
+        .with_children(|col| {
+            col.spawn(Node {
+                flex_direction: FlexDirection::Row,
+                align_items: AlignItems::Center,
+                column_gap: VAL_SPACE_3,
+                flex_wrap: FlexWrap::Wrap,
+                row_gap: VAL_SPACE_2,
+                ..default()
+            })
+            .with_children(|row| {
+                small_button(
+                    row,
+                    SettingsButton::ExportData,
+                    "Export data",
+                    "Write settings, stats, achievements and progress to one backup file"
+                        .to_string(),
+                    button_font.clone(),
+                );
+                small_button(
+                    row,
+                    SettingsButton::ImportData,
+                    "Import data",
+                    "Restore all saves from the backup file (replaces current data)".to_string(),
+                    button_font.clone(),
+                );
+            });
+            col.spawn((
+                Text::new(format!(
+                    "Backup file: {}",
+                    solitaire_data::data_bundle_path()
+                        .map_or_else(|| "unavailable".to_string(), |p| p.display().to_string())
+                )),
+                caption_font,
+                TextColor(TEXT_SECONDARY),
+            ));
+        });
+}
+
+/// Phase M (sync transparency): renders what the most recent sync merge
+/// did — a clean-merge caption, or one line per conflicting field with
+/// both values, so the player can see exactly which numbers were
+/// reconciled and how.
+fn spawn_sync_merge_summary(
+    body: &mut ChildSpawnerCommands,
+    conflict_log: Option<&crate::resources::SyncConflictLog>,
+    font_res: Option<&FontResource>,
+) {
+    let Some(summary) = conflict_log.and_then(|log| log.0.as_ref()) else {
+        return;
+    };
+    let caption_font = TextFont {
+        font: font_res.map(|f| f.0.clone()).unwrap_or_default(),
+        font_size: TYPE_CAPTION,
+        ..default()
+    };
+    let when = summary.at.format("%H:%M UTC");
+    if summary.conflicts.is_empty() {
+        body.spawn((
+            SyncMergeSummaryText,
+            Text::new(format!("Last merge at {when}: no conflicts")),
+            caption_font,
+            TextColor(TEXT_SECONDARY),
+        ));
+        return;
+    }
+    let n = summary.conflicts.len();
+    let plural = if n == 1 { "conflict" } else { "conflicts" };
+    body.spawn((
+        SyncMergeSummaryText,
+        Text::new(format!(
+            "Last merge at {when}: {n} {plural} — kept newer values"
+        )),
+        caption_font.clone(),
+        TextColor(TEXT_SECONDARY),
+    ));
+    for c in &summary.conflicts {
+        body.spawn((
+            Text::new(format!(
+                "  {} — this device: {} / server: {}",
+                c.field, c.local_value, c.remote_value
+            )),
+            caption_font.clone(),
+            TextColor(TEXT_SECONDARY),
+        ));
+    }
 }
 
 /// Section divider — small lavender label inside the scrollable body.

solitaire_engine/src/settings_plugin/updates.rs

@@ -9,8 +9,10 @@ use crate::font_plugin::FontResource;
 use crate::progress_plugin::ProgressResource;
 use crate::resources::{SettingsScrollPos, SyncStatus, SyncStatusResource};
 use crate::theme::ThemeThumbnailCache;
+use crate::ui_glass::{GlassSurface, glass_decorations};
 use crate::ui_modal::ModalScrim;
 use crate::ui_theme::{BORDER_SUBTLE_HC, HighContrastBackground, HighContrastBorder};
+use bevy::ui::{BackgroundGradient, BorderGradient};
 
 /// Spawns the Settings panel when `SettingsScreen` becomes `true`;
 /// despawns it when it becomes `false`.
@@ -30,6 +32,7 @@ pub(super) fn sync_settings_panel_visibility(
     theme_registry: Option<Res<crate::theme::ThemeRegistry>>,
     theme_thumbs: Option<Res<ThemeThumbnailCache>>,
     card_images: Option<Res<crate::card_plugin::CardImageSet>>,
+    conflict_log: Option<Res<crate::resources::SyncConflictLog>>,
 ) {
     if !screen.is_changed() {
         return;
@@ -45,6 +48,7 @@ pub(super) fn sync_settings_panel_visibility(
                 theme_registry.as_deref(),
                 theme_thumbs.as_deref(),
                 card_images.as_deref(),
+                conflict_log.as_deref(),
                 scroll_pos.0,
                 active_tab.0,
             );
@@ -74,6 +78,7 @@ fn build_panel(
     theme_registry: Option<&crate::theme::ThemeRegistry>,
     theme_thumbs: Option<&ThemeThumbnailCache>,
     card_images: Option<&crate::card_plugin::CardImageSet>,
+    conflict_log: Option<&crate::resources::SyncConflictLog>,
     scroll_offset: f32,
     active_tab: SettingsTab,
 ) {
@@ -123,6 +128,7 @@ fn build_panel(
         scroll_offset,
         font_res,
         theme_overrides_back,
+        conflict_log,
         active_tab,
     );
 }
@@ -143,6 +149,7 @@ pub(super) fn rebuild_panel_on_tab_change(
     theme_registry: Option<Res<crate::theme::ThemeRegistry>>,
     theme_thumbs: Option<Res<ThemeThumbnailCache>>,
     card_images: Option<Res<crate::card_plugin::CardImageSet>>,
+    conflict_log: Option<Res<crate::resources::SyncConflictLog>>,
 ) {
     if !active_tab.is_changed() || active_tab.is_added() {
         return;
@@ -165,6 +172,7 @@ pub(super) fn rebuild_panel_on_tab_change(
         theme_registry.as_deref(),
         theme_thumbs.as_deref(),
         card_images.as_deref(),
+        conflict_log.as_deref(),
         0.0,
         active_tab.0,
     );
@@ -330,6 +338,41 @@ pub(super) fn update_reduce_motion_text(
     }
 }
 
+pub(super) fn update_reduce_transparency_text(
+    settings: Res<SettingsResource>,
+    mut text_nodes: Query<&mut Text, With<ReduceTransparencyText>>,
+) {
+    if !settings.is_changed() {
+        return;
+    }
+    for mut text in &mut text_nodes {
+        **text = on_off_label(settings.0.reduce_transparency_mode);
+    }
+}
+
+/// Retargets every [`GlassSurface`]'s sheen + rim gradients when the
+/// reduce-transparency or high-contrast toggles change. Runs on
+/// `SettingsResource` change and on newly added surfaces (so glass
+/// spawned after startup picks up an already-active toggle). Parallel to
+/// [`update_high_contrast_borders`]: same trigger, different components.
+pub(super) fn update_glass_surfaces(
+    settings: Res<SettingsResource>,
+    mut surfaces: Query<(&mut BackgroundGradient, &mut BorderGradient), With<GlassSurface>>,
+    added: Query<(), Added<GlassSurface>>,
+) {
+    if !settings.is_changed() && added.is_empty() {
+        return;
+    }
+    let (sheen, rim) = glass_decorations(
+        settings.0.reduce_transparency_mode,
+        settings.0.high_contrast_mode,
+    );
+    for (mut s, mut r) in &mut surfaces {
+        *s = sheen.clone();
+        *r = rim.clone();
+    }
+}
+
 pub(super) fn update_touch_input_mode_text(
     settings: Res<SettingsResource>,
     mut text_nodes: Query<&mut Text, With<TouchInputModeText>>,
@@ -515,6 +558,58 @@ pub(super) fn touch_input_mode_label(mode: &solitaire_data::settings::TouchInput
     }
 }
 
+/// The four UI-scale steps the settings row cycles through (Phase K).
+pub(super) const UI_SCALE_STEPS: [f32; 4] = [0.9, 1.0, 1.15, 1.3];
+
+/// The next UI-scale step after `current`, wrapping 130 % → 90 %. A
+/// hand-edited value between steps advances to the first step larger
+/// than it, so the cycle always makes visible progress.
+pub(super) fn next_ui_scale(current: f32) -> f32 {
+    for step in UI_SCALE_STEPS {
+        if step > current + 0.001 {
+            return step;
+        }
+    }
+    UI_SCALE_STEPS[0]
+}
+
+/// Display string for the UI-scale row, e.g. `"115%"`.
+pub(super) fn ui_scale_label(scale: f32) -> String {
+    format!("{:.0}%", scale * 100.0)
+}
+
+/// Refreshes the live UI-scale value text whenever settings change.
+pub(super) fn update_ui_scale_text(
+    settings: Res<SettingsResource>,
+    mut text_nodes: Query<&mut Text, With<UiScaleText>>,
+) {
+    if !settings.is_changed() {
+        return;
+    }
+    for mut text in &mut text_nodes {
+        **text = ui_scale_label(settings.0.ui_scale);
+    }
+}
+
+/// Applies `Settings::ui_scale` to the live [`bevy::ui::UiScale`]
+/// resource — at startup (first change tick) and whenever the setting
+/// changes. Absent under `MinimalPlugins` (no `bevy_ui`), hence the
+/// `Option`; the table is unaffected either way (`compute_layout`
+/// owns world-space sizing, not UI scale).
+pub(super) fn sync_ui_scale_resource(
+    settings: Res<SettingsResource>,
+    ui_scale: Option<ResMut<UiScale>>,
+) {
+    let Some(mut ui_scale) = ui_scale else { return };
+    if !settings.is_changed() {
+        return;
+    }
+    let target = settings.0.ui_scale;
+    if (ui_scale.0 - target).abs() > f32::EPSILON {
+        ui_scale.0 = target;
+    }
+}
+
 /// Display string for the "Smart window size" toggle. The argument
 /// is the *enabled* state (i.e. the inverse of the underlying
 /// `disable_smart_default_size` field) so reading the label gives

solitaire_engine/src/splash_plugin.rs

@@ -99,7 +99,18 @@ impl Plugin for SplashPlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(Startup, spawn_splash).add_systems(
             Update,
-            (dismiss_splash_on_input, advance_splash, pulse_splash_cursor).chain(),
+            // Splash text/fade writers touch UI entities only — they join
+            // the UiTextFx club (disjoint from board/anim sets) and, for
+            // the reduce-motion read in the pulse, the screen-plugin
+            // settings club. Disjoint from the HUD button painters for the
+            // same entity-domain reason (#143).
+            (dismiss_splash_on_input, advance_splash, pulse_splash_cursor)
+                .chain()
+                .in_set(crate::ui_theme::UiTextFx)
+                .ambiguous_with(crate::ui_theme::UiTextFx)
+                .ambiguous_with(crate::hud_plugin::HudButtons)
+                .in_set(crate::settings_plugin::SettingsAccess)
+                .ambiguous_with(crate::settings_plugin::SettingsAccess),
         );
     }
 }

solitaire_engine/src/stats_plugin.rs

@@ -30,7 +30,7 @@ use crate::ui_modal::{ButtonVariant, ModalButton, spawn_modal_button};
 use crate::ui_theme::{
     ACCENT_PRIMARY, BG_ELEVATED_HI, BORDER_SUBTLE, HighContrastBorder, RADIUS_SM, STATE_INFO,
     STATE_WARNING, STREAK_MILESTONES, TEXT_PRIMARY, TEXT_SECONDARY, TYPE_BODY, TYPE_BODY_LG,
-    TYPE_CAPTION, TYPE_HEADLINE, VAL_SPACE_1, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4,
+    TYPE_HEADLINE, VAL_SPACE_1, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4,
 };
 
 /// Bevy resource wrapping the current stats.
@@ -46,6 +46,14 @@ pub struct StatsStoragePath(pub Option<PathBuf>);
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct StatsUpdate;
 
+/// Set holding the abandon-recorder (`update_stats_on_new_game`). It must
+/// read the outgoing game's `move_count` before any mode-start handler or
+/// `GameMutation` clobbers the game state — mode plugins order their reset
+/// handlers `.after(AbandonRecord)` via `crate::game_plugin::ModeStart`
+/// (#143).
+#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AbandonRecord;
+
 /// Marker component on the stats overlay root node.
 #[derive(Component, Debug)]
 pub struct StatsScreen;
@@ -205,10 +213,34 @@ impl Plugin for StatsPlugin {
             // constraints (win_summary_plugin: cache_win_data.before(StatsUpdate)),
             // and a system cannot be both inside a set and individually before a
             // set-level ordering constraint.
-            .add_systems(Update, update_stats_on_new_game.before(GameMutation))
             .add_systems(
                 Update,
-                update_stats_on_win.after(GameMutation).in_set(StatsUpdate),
+                update_stats_on_new_game
+                    .in_set(AbandonRecord)
+                    .before(GameMutation)
+                    // Reads the shared new-game request stream via its own
+                    // cursor — append order is irrelevant, so it joins the
+                    // self-ambiguous writer club (NewGameRequestWriters must
+                    // not carry set-level edges; see its doc). The explicit
+                    // edges pin it after the pause/settings/selection
+                    // mutators and the pre-mutation game-state spine it
+                    // reads `move_count` from (#143).
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                    .after(crate::game_plugin::PreMutation)
+                    .after(crate::pause_plugin::PauseMutation)
+                    .after(crate::settings_plugin::SettingsMutation)
+                    .after(crate::selection_plugin::SelectionKeySet),
+            )
+            .add_systems(
+                Update,
+                update_stats_on_win
+                    .after(GameMutation)
+                    .in_set(StatsUpdate)
+                    // Also emits toasts (streak milestones) — join the
+                    // self-ambiguous writer club (#143).
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
             )
             .add_systems(
                 Update,
@@ -216,29 +248,69 @@ impl Plugin for StatsPlugin {
                 // the NewGameRequestEvent it emits is not visible to
                 // update_stats_on_new_game in the same frame — otherwise
                 // record_abandoned() fires twice on every forfeit (#21).
+                // It drains the ForfeitEvent the pause/forfeit modal chain
+                // emits, and shares the new-game request stream with the
+                // other writers (#143).
                 handle_forfeit
                     .before(GameMutation)
-                    .before(update_stats_on_new_game),
+                    .before(update_stats_on_new_game)
+                    .after(crate::pause_plugin::PauseMutation)
+                    .after(crate::selection_plugin::SelectionKeySet)
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
             )
             // Open/close/tab handling moved to `you_hub_plugin`
             // (Phase E) — this plugin now owns body content, replay
             // selector behavior, and scroll.
-            .add_systems(Update, refresh_replay_history_on_win.after(GameMutation))
-            .add_systems(Update, handle_watch_replay_button)
-            .add_systems(Update, handle_copy_share_link_button)
+            //
+            // Stats overlay UI: one deterministic chain — every member
+            // touches the replay-selector state or the overlay's nodes, and
+            // handle_watch_replay_button resets the live game, so the chain
+            // sits between GameMutation and the auto-complete driver on the
+            // game-state timeline (#143). The toast-emitting members join
+            // the self-ambiguous InfoToastWriters set so the toast pipeline
+            // (AnimFx) drains them this frame.
             .add_systems(
                 Update,
                 (
+                    refresh_replay_history_on_win,
                     handle_replay_selector_buttons,
-                    repaint_replay_selector_caption,
-                    repaint_replay_selector_detail,
+                    // Marker-filtered Text repaints — disjoint from the
+                    // HUD text painters (UiTextFx club, #143).
+                    repaint_replay_selector_caption
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    repaint_replay_selector_detail
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    handle_watch_replay_button
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
+                    handle_copy_share_link_button
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
                 )
-                    .chain(),
+                    .chain()
+                    .after(GameMutation)
+                    // The overlay repaints read this frame's settled stats,
+                    // progress, and achievement evaluation (level line,
+                    // streak).
+                    .after(StatsUpdate)
+                    .after(crate::progress_plugin::ProgressUpdate)
+                    .after(crate::achievement_plugin::AchievementEval)
+                    .before(crate::auto_complete_plugin::AutoComplete),
             )
-            .add_systems(Update, scroll_stats_panel)
             .add_systems(
                 Update,
-                crate::ui_modal::touch_scroll_panel::<StatsScrollable>,
+                scroll_stats_panel
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
+            )
+            .add_systems(
+                Update,
+                crate::ui_modal::touch_scroll_panel::<StatsScrollable>
+                    .in_set(crate::ui_modal::PanelScroll)
+                    .ambiguous_with(crate::ui_modal::PanelScroll),
             );
     }
 }
@@ -719,25 +791,17 @@ pub(crate) fn spawn_stats_body(
             },
         ))
         .with_children(|body| {
-            // First-launch caption — sits above the grid as gentle nudge so
+            // First-launch empty state (Phase L) — sits above the grid so
             // the wall of em-dashes reads as "nothing to track yet" rather
             // than as broken state.
             if is_first_launch {
-                body.spawn((
-                    Text::new("Play a game to start tracking stats."),
-                    TextFont {
-                        font_size: TYPE_CAPTION,
-                        ..default()
-                    },
-                    TextColor(TEXT_SECONDARY),
-                    Node {
-                        margin: UiRect {
-                            bottom: VAL_SPACE_2,
-                            ..default()
-                        },
-                        ..default()
-                    },
-                ));
+                crate::ui_modal::spawn_empty_state(
+                    body,
+                    "\u{2663}",
+                    "Play a game to start tracking stats.",
+                    None,
+                    font_res,
+                );
             }
 
             // --- primary stat cells grid ---
@@ -893,6 +957,20 @@ pub(crate) fn spawn_replays_body(
     selected_index: usize,
     font_res: Option<&FontResource>,
 ) {
+    // Standard empty state (Phase L) — the selector / Watch / Copy
+    // controls only spawn when there is something to select, so their
+    // handlers all no-op via their existing empty-query paths.
+    if replays.is_empty() {
+        crate::ui_modal::spawn_empty_state(
+            card,
+            "\u{2666}",
+            "No replays yet.",
+            Some("Every win records a replay here automatically."),
+            font_res,
+        );
+        return;
+    }
+
     let font_handle = font_res.map(|f| f.0.clone()).unwrap_or_default();
     let font_row = TextFont {
         font: font_handle,

solitaire_engine/src/sync_plugin.rs

@@ -26,11 +26,15 @@ use solitaire_sync::{SyncPayload, merge};
 
 use crate::achievement_plugin::{AchievementsResource, AchievementsStoragePath};
 use crate::events::{
-    GameWonEvent, ManualSyncRequestEvent, SyncConfigureRequestEvent, WarningToastEvent,
+    GameWonEvent, InfoToastEvent, ManualSyncRequestEvent, SyncConfigureRequestEvent,
+    WarningToastEvent,
 };
 use crate::game_plugin::RecordingReplay;
 use crate::progress_plugin::{ProgressResource, ProgressStoragePath};
-use crate::resources::{GameStateResource, SyncStatus, SyncStatusResource, TokioRuntimeResource};
+use crate::resources::{
+    GameStateResource, SyncConflictLog, SyncMergeSummary, SyncStatus, SyncStatusResource,
+    TokioRuntimeResource,
+};
 use crate::stats_plugin::{
     LatestReplayPath, ReplayHistoryResource, StatsResource, StatsStoragePath,
 };
@@ -106,9 +110,13 @@ impl Plugin for SyncPlugin {
             .init_resource::<PullTaskResult>()
             .init_resource::<PullTask>()
             .init_resource::<PendingReplayUpload>()
+            .init_resource::<SyncConflictLog>()
             .add_message::<ManualSyncRequestEvent>()
             .add_message::<SyncConfigureRequestEvent>()
-            .add_message::<WarningToastEvent>();
+            .add_message::<WarningToastEvent>()
+            // Idempotent — GamePlugin also registers it; re-register so the
+            // conflict-summary toast works under MinimalPlugins tests.
+            .add_message::<InfoToastEvent>();
 
         // Build the shared Tokio runtime; disable all network sync if the OS
         // refuses to create threads (resource-limited environments, sandboxed
@@ -198,6 +206,8 @@ fn poll_pull_result(
     progress_path: Res<ProgressStoragePath>,
     mut configure_sync: MessageWriter<SyncConfigureRequestEvent>,
     mut warning_toast: MessageWriter<WarningToastEvent>,
+    mut conflict_log: ResMut<SyncConflictLog>,
+    mut info_toast: MessageWriter<InfoToastEvent>,
 ) {
     let Some(task) = task_res.0.as_mut() else {
         return;
@@ -210,7 +220,21 @@ fn poll_pull_result(
     match result {
         Ok(remote) => {
             let local = build_payload(&stats.0, &achievements.0, &progress.0);
-            let (merged, _conflicts) = merge(&local, &remote);
+            let (merged, conflicts) = merge(&local, &remote);
+
+            // Phase M (sync transparency): keep the conflict details for
+            // the Account tab and summarise non-clean merges in a toast.
+            if !conflicts.is_empty() {
+                let n = conflicts.len();
+                let plural = if n == 1 { "conflict" } else { "conflicts" };
+                info_toast.write(InfoToastEvent(format!(
+                    "Synced — {n} {plural}, kept newer values"
+                )));
+            }
+            conflict_log.0 = Some(SyncMergeSummary {
+                at: Utc::now(),
+                conflicts,
+            });
 
             // Persist merged state atomically.
             if let Some(p) = &stats_path.0

solitaire_engine/src/table_plugin.rs

@@ -112,7 +112,12 @@ impl Plugin for TablePlugin {
                     // paint pipeline — markers and cards share Sprite/
                     // Transform access (#143).
                     (
-                        apply_theme_on_settings_change,
+                        // Drains SettingsChangedEvent via cursor — a home
+                        // deal-option edit (post-mutation SettingsAccess
+                        // writer) surfacing one frame later repaints one
+                        // frame later, which is invisible (#143).
+                        apply_theme_on_settings_change
+                            .ambiguous_with(crate::settings_plugin::SettingsAccess),
                         apply_hint_pile_highlight,
                         tick_hint_pile_highlights,
                         sync_pile_marker_visibility.after(GameMutation),

solitaire_engine/src/theme_store_plugin.rs

@@ -14,6 +14,9 @@
 //! filesystem-based; the plugin is gated out on wasm32 alongside
 //! `SyncPlugin`.
 
+use std::collections::HashMap;
+
+use bevy::asset::RenderAssetUsages;
 use bevy::prelude::*;
 use bevy::tasks::{AsyncComputeTaskPool, Task, futures_lite::future};
 use thiserror::Error;
@@ -29,8 +32,8 @@ use crate::resources::TokioRuntimeResource;
 use crate::settings_plugin::{SettingsPanel, SettingsResource};
 use crate::theme::{ImportError, ThemeRegistry, import_theme, refresh_registry};
 use crate::ui_modal::{
-    ButtonVariant, ModalScrim, ScrimDismissible, spawn_modal, spawn_modal_actions,
-    spawn_modal_button, spawn_modal_header,
+    ButtonVariant, ModalScrim, ScrimDismissible, spawn_empty_state, spawn_modal,
+    spawn_modal_actions, spawn_modal_button, spawn_modal_header,
 };
 use crate::ui_theme::{
     BORDER_SUBTLE, TEXT_PRIMARY, TEXT_SECONDARY, TYPE_BODY, TYPE_CAPTION, VAL_SPACE_2, VAL_SPACE_3,
@@ -105,6 +108,21 @@ struct InstallTask(Option<(String, Task<InstallResult>)>);
 #[derive(Resource, Default)]
 struct StoreBaseUrl(Option<String>);
 
+/// Decoded preview thumbnails by theme id (Phase H). Session-lifetime:
+/// previews survive closing and reopening the store, so a revisit
+/// renders instantly without refetching.
+#[derive(Resource, Default)]
+struct PreviewCache(HashMap<String, Handle<Image>>);
+
+/// One in-flight preview download: raw PNG bytes or the fetch error.
+type PreviewFetch = Task<Result<Vec<u8>, ThemeStoreError>>;
+
+/// In-flight preview downloads, one per catalog entry that advertises
+/// a `preview_url` not already in [`PreviewCache`]. `String` is the
+/// theme id the bytes belong to.
+#[derive(Resource, Default)]
+struct PreviewTasks(Vec<(String, PreviewFetch)>);
+
 // ---------------------------------------------------------------------------
 // Plugin
 // ---------------------------------------------------------------------------
@@ -118,6 +136,8 @@ impl Plugin for ThemeStorePlugin {
             .init_resource::<CatalogTask>()
             .init_resource::<InstallTask>()
             .init_resource::<StoreBaseUrl>()
+            .init_resource::<PreviewCache>()
+            .init_resource::<PreviewTasks>()
             // Esc-close reads keyboard input; register defensively so
             // the plugin works under MinimalPlugins in tests.
             .init_resource::<ButtonInput<KeyCode>>()
@@ -129,6 +149,7 @@ impl Plugin for ThemeStorePlugin {
                 (
                     handle_open_request,
                     poll_catalog_task,
+                    poll_preview_tasks,
                     handle_install_buttons,
                     poll_install_task,
                     handle_close_button,
@@ -176,6 +197,7 @@ fn handle_open_request(
     mut catalog_task: ResMut<CatalogTask>,
     mut store_base: ResMut<StoreBaseUrl>,
     mut warning_toast: MessageWriter<WarningToastEvent>,
+    previews: Res<PreviewCache>,
     mut commands: Commands,
     font_res: Option<Res<FontResource>>,
 ) {
@@ -207,16 +229,28 @@ fn handle_open_request(
         rt.block_on(async { ThemeStoreClient::new(base_url).fetch_catalog().await })
     }));
 
-    spawn_store_modal(&mut commands, &catalog_state, None, font_res.as_deref());
+    spawn_store_modal(
+        &mut commands,
+        &catalog_state,
+        None,
+        &previews,
+        font_res.as_deref(),
+    );
 }
 
-/// Polls the catalog fetch; on completion updates [`CatalogState`] and
+/// Polls the catalog fetch; on completion updates [`CatalogState`],
+/// kicks off preview downloads for entries not yet in the cache, and
 /// rebuilds the modal if it is still open.
+#[allow(clippy::too_many_arguments)]
 fn poll_catalog_task(
     mut catalog_task: ResMut<CatalogTask>,
     mut catalog_state: ResMut<CatalogState>,
     screens: Query<Entity, With<ThemeStoreScreen>>,
     registry: Option<Res<ThemeRegistry>>,
+    rt: Option<Res<TokioRuntimeResource>>,
+    store_base: Res<StoreBaseUrl>,
+    previews: Res<PreviewCache>,
+    mut preview_tasks: ResMut<PreviewTasks>,
     mut commands: Commands,
     font_res: Option<Res<FontResource>>,
 ) {
@@ -229,7 +263,29 @@ fn poll_catalog_task(
     catalog_task.0 = None;
 
     *catalog_state = match result {
-        Ok(entries) => CatalogState::Loaded(entries),
+        Ok(entries) => {
+            // Fetch previews for anything new. Decorative — failures
+            // just leave the row text-only, so errors only log.
+            if let (Some(rt), Some(base_url)) = (rt.as_ref(), store_base.0.as_deref()) {
+                for entry in entries
+                    .iter()
+                    .filter(|e| e.preview_url.is_some() && !previews.0.contains_key(&e.id))
+                {
+                    let rt = rt.0.clone();
+                    let base_url = base_url.to_owned();
+                    let entry = entry.clone();
+                    preview_tasks.0.push((
+                        entry.id.clone(),
+                        AsyncComputeTaskPool::get().spawn(async move {
+                            rt.block_on(async {
+                                ThemeStoreClient::new(base_url).fetch_preview(&entry).await
+                            })
+                        }),
+                    ));
+                }
+            }
+            CatalogState::Loaded(entries)
+        }
         Err(e) => {
             warn!("theme store: catalog fetch failed: {e}");
             CatalogState::Error(e.to_string())
@@ -241,10 +297,69 @@ fn poll_catalog_task(
         &mut commands,
         &catalog_state,
         registry.as_deref(),
+        &previews,
         font_res.as_deref(),
     );
 }
 
+/// Polls in-flight preview downloads. Each finished PNG is decoded into
+/// an [`Image`] asset and cached by theme id; the open modal rebuilds
+/// once per frame that added at least one preview, so thumbnails pop in
+/// as they arrive. Failures log and leave the row text-only. Skipped
+/// entirely when `Assets<Image>` is absent (`MinimalPlugins` tests).
+#[allow(clippy::too_many_arguments)]
+fn poll_preview_tasks(
+    mut preview_tasks: ResMut<PreviewTasks>,
+    mut previews: ResMut<PreviewCache>,
+    images: Option<ResMut<Assets<Image>>>,
+    catalog_state: Res<CatalogState>,
+    screens: Query<Entity, With<ThemeStoreScreen>>,
+    registry: Option<Res<ThemeRegistry>>,
+    mut commands: Commands,
+    font_res: Option<Res<FontResource>>,
+) {
+    if preview_tasks.0.is_empty() {
+        return;
+    }
+    let Some(mut images) = images else {
+        return;
+    };
+
+    let mut added = false;
+    preview_tasks.0.retain_mut(|(id, task)| {
+        let Some(result) = future::block_on(future::poll_once(task)) else {
+            return true; // still downloading
+        };
+        match result {
+            Ok(bytes) => match image::load_from_memory(&bytes) {
+                Ok(dyn_img) => {
+                    let handle = images.add(Image::from_dynamic(
+                        dyn_img,
+                        true,
+                        RenderAssetUsages::RENDER_WORLD,
+                    ));
+                    previews.0.insert(id.clone(), handle);
+                    added = true;
+                }
+                Err(e) => warn!("theme store: preview for '{id}' failed to decode: {e}"),
+            },
+            Err(e) => warn!("theme store: preview fetch for '{id}' failed: {e}"),
+        }
+        false
+    });
+
+    if added {
+        rebuild_open_modal(
+            &screens,
+            &mut commands,
+            &catalog_state,
+            registry.as_deref(),
+            &previews,
+            font_res.as_deref(),
+        );
+    }
+}
+
 /// Starts a download + import task when an Install button is pressed.
 /// One install at a time; repeat clicks while busy are ignored.
 fn handle_install_buttons(
@@ -308,6 +423,7 @@ fn poll_install_task(
     screens: Query<Entity, With<ThemeStoreScreen>>,
     mut info_toast: MessageWriter<InfoToastEvent>,
     mut warning_toast: MessageWriter<WarningToastEvent>,
+    previews: Res<PreviewCache>,
     mut commands: Commands,
     font_res: Option<Res<FontResource>>,
 ) {
@@ -343,6 +459,7 @@ fn poll_install_task(
         &mut commands,
         &catalog_state,
         registry.as_deref(),
+        &previews,
         font_res.as_deref(),
     );
 }
@@ -378,11 +495,12 @@ fn rebuild_open_modal(
     commands: &mut Commands,
     catalog_state: &CatalogState,
     registry: Option<&ThemeRegistry>,
+    previews: &PreviewCache,
     font_res: Option<&FontResource>,
 ) {
     for entity in screens {
         commands.entity(entity).despawn();
-        spawn_store_modal(commands, catalog_state, registry, font_res);
+        spawn_store_modal(commands, catalog_state, registry, previews, font_res);
     }
 }
 
@@ -391,6 +509,7 @@ fn spawn_store_modal(
     commands: &mut Commands,
     catalog_state: &CatalogState,
     registry: Option<&ThemeRegistry>,
+    previews: &PreviewCache,
     font_res: Option<&FontResource>,
 ) {
     let body_font = TextFont {
@@ -409,31 +528,45 @@ fn spawn_store_modal(
 
         match catalog_state {
             CatalogState::Idle | CatalogState::Loading => {
-                card.spawn((
-                    Text::new("Loading catalog…"),
-                    body_font.clone(),
-                    TextColor(TEXT_SECONDARY),
-                ));
+                spawn_empty_state(
+                    card,
+                    "\u{21BB}",
+                    "Loading the catalog\u{2026}",
+                    None,
+                    font_res,
+                );
             }
             CatalogState::Error(msg) => {
-                card.spawn((
-                    Text::new(format!("Could not load the catalog: {msg}")),
-                    body_font.clone(),
-                    TextColor(TEXT_SECONDARY),
-                ));
+                spawn_empty_state(
+                    card,
+                    "!",
+                    "Couldn't load the catalog.",
+                    Some(msg.as_str()),
+                    font_res,
+                );
             }
             CatalogState::Loaded(entries) if entries.is_empty() => {
-                card.spawn((
-                    Text::new("The server has no themes yet."),
-                    body_font.clone(),
-                    TextColor(TEXT_SECONDARY),
-                ));
+                spawn_empty_state(
+                    card,
+                    "#",
+                    "The server has no themes yet.",
+                    Some("Themes dropped into the server's theme_store folder appear here."),
+                    font_res,
+                );
             }
             CatalogState::Loaded(entries) => {
                 for entry in entries {
                     let installed =
                         registry.is_some_and(|registry| registry.find(&entry.id).is_some());
-                    spawn_store_row(card, entry, installed, &body_font, &caption_font, font_res);
+                    spawn_store_row(
+                        card,
+                        entry,
+                        installed,
+                        previews.0.get(&entry.id),
+                        &body_font,
+                        &caption_font,
+                        font_res,
+                    );
                 }
             }
         }
@@ -452,12 +585,20 @@ fn spawn_store_modal(
     commands.entity(scrim).insert(ScrimDismissible);
 }
 
-/// One catalog row: name + author/size caption on the left, Install
-/// button (or "Installed" caption) on the right.
+/// Height of a row's preview thumbnail in logical pixels; the width
+/// follows the theme's own `card_aspect` so a preview is never
+/// stretched.
+const PREVIEW_THUMB_HEIGHT_PX: f32 = 72.0;
+
+/// One catalog row: preview thumbnail (when downloaded) + name +
+/// author/size caption on the left, Install button (or "Installed"
+/// caption) on the right.
+#[allow(clippy::too_many_arguments)]
 fn spawn_store_row(
     parent: &mut ChildSpawnerCommands,
     entry: &ThemeCatalogEntry,
     installed: bool,
+    preview: Option<&Handle<Image>>,
     body_font: &TextFont,
     caption_font: &TextFont,
     font_res: Option<&FontResource>,
@@ -477,6 +618,25 @@ fn spawn_store_row(
         ))
         .with_children(|row| {
             row.spawn(Node {
+                flex_direction: FlexDirection::Row,
+                align_items: AlignItems::Center,
+                column_gap: VAL_SPACE_3,
+                ..default()
+            })
+            .with_children(|left| {
+                if let Some(handle) = preview {
+                    let (aw, ah) = entry.card_aspect;
+                    let width = PREVIEW_THUMB_HEIGHT_PX * aw.max(1) as f32 / ah.max(1) as f32;
+                    left.spawn((
+                        ImageNode::new(handle.clone()),
+                        Node {
+                            width: Val::Px(width),
+                            height: Val::Px(PREVIEW_THUMB_HEIGHT_PX),
+                            ..default()
+                        },
+                    ));
+                }
+                left.spawn(Node {
                     flex_direction: FlexDirection::Column,
                     row_gap: VAL_SPACE_2,
                     ..default()
@@ -497,6 +657,7 @@ fn spawn_store_row(
                         TextColor(TEXT_SECONDARY),
                     ));
                 });
+            });
             if installed {
                 row.spawn((
                     Text::new("Installed"),
@@ -661,4 +822,85 @@ mod tests {
         ));
         assert_eq!(screen_count(&mut app), 1);
     }
+
+    // -----------------------------------------------------------------------
+    // Phase H part 2: preview thumbnails
+    // -----------------------------------------------------------------------
+
+    fn catalog_entry(id: &str, preview: bool) -> ThemeCatalogEntry {
+        ThemeCatalogEntry {
+            id: id.into(),
+            name: id.into(),
+            author: "Test".into(),
+            version: "1.0.0".into(),
+            card_aspect: (2, 3),
+            size_bytes: 1024,
+            sha256: "00".into(),
+            download_url: format!("/api/themes/{id}/download"),
+            preview_url: preview.then(|| format!("/api/themes/{id}/preview")),
+        }
+    }
+
+    /// A row whose theme id is in the [`PreviewCache`] renders an
+    /// `ImageNode` thumbnail; a row without one stays text-only.
+    #[test]
+    fn loaded_row_shows_preview_thumbnail_only_when_cached() {
+        let mut app = headless_app();
+        let cached = catalog_entry("with-preview", true);
+        let uncached = catalog_entry("without-preview", false);
+
+        let mut cache = PreviewCache::default();
+        cache
+            .0
+            .insert(cached.id.clone(), Handle::<Image>::default());
+        let state = CatalogState::Loaded(vec![cached, uncached]);
+
+        {
+            let world = app.world_mut();
+            let mut commands = world.commands();
+            spawn_store_modal(&mut commands, &state, None, &cache, None);
+        }
+        app.update();
+
+        let thumbs = app
+            .world_mut()
+            .query::<&ImageNode>()
+            .iter(app.world())
+            .count();
+        assert_eq!(
+            thumbs, 1,
+            "exactly the cached entry must render a preview thumbnail"
+        );
+    }
+
+    /// The thumbnail width follows the theme's own card aspect so a
+    /// preview never renders stretched.
+    #[test]
+    fn preview_thumbnail_width_follows_card_aspect() {
+        let mut app = headless_app();
+        let mut entry = catalog_entry("wide", true);
+        entry.card_aspect = (1, 1); // square theme art
+        let mut cache = PreviewCache::default();
+        cache.0.insert(entry.id.clone(), Handle::<Image>::default());
+        let state = CatalogState::Loaded(vec![entry]);
+
+        {
+            let world = app.world_mut();
+            let mut commands = world.commands();
+            spawn_store_modal(&mut commands, &state, None, &cache, None);
+        }
+        app.update();
+
+        let node = app
+            .world_mut()
+            .query_filtered::<&Node, With<ImageNode>>()
+            .single(app.world())
+            .expect("thumbnail node must exist");
+        assert_eq!(node.height, Val::Px(PREVIEW_THUMB_HEIGHT_PX));
+        assert_eq!(
+            node.width,
+            Val::Px(PREVIEW_THUMB_HEIGHT_PX),
+            "a 1:1 aspect must yield a square thumbnail"
+        );
+    }
 }

solitaire_engine/src/time_attack_plugin.rs

@@ -109,13 +109,41 @@ impl Plugin for TimeAttackPlugin {
             .add_message::<NewGameRequestEvent>()
             .add_message::<StartTimeAttackRequestEvent>()
             .add_message::<InfoToastEvent>()
+            // ModeStart places it between the stats abandon-recorder and
+            // GameMutation; it shares the new-game request/toast streams
+            // with the other writers (#143).
             .add_systems(
                 Update,
-                handle_start_time_attack_request.before(GameMutation),
+                handle_start_time_attack_request
+                    .in_set(crate::game_plugin::ModeStart)
+                    .in_set(crate::game_plugin::NewGameRequestWriters)
+                    .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            )
+            // One post-mutation chain for the TimeAttackResource writers:
+            // clock tick, win auto-deal, then the debounced disk save.
+            // The start handler (ModeStart, pre-mutation) is ordered
+            // against all three transitively. auto_deal's new-game request
+            // is drained wholesale next frame, so it joins the writer club
+            // (#143). PausedResource is settled: PauseMutation < GameMutation.
+            .add_systems(
+                Update,
+                (
+                    advance_time_attack,
+                    auto_deal_on_time_attack_win
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
+                    auto_save_time_attack_session,
+                )
+                    .chain()
+                    .after(GameMutation)
+                    // The HUD clock (after AutoComplete) and the ended-toast
+                    // handler (AnimFx) read what this chain writes — settle
+                    // it before both (#143).
+                    .before(crate::auto_complete_plugin::AutoComplete)
+                    .before(crate::animation_plugin::AnimFx),
             )
-            .add_systems(Update, advance_time_attack)
-            .add_systems(Update, auto_deal_on_time_attack_win.after(GameMutation))
-            .add_systems(Update, auto_save_time_attack_session)
             .add_systems(Last, save_time_attack_session_on_exit);
     }
 }

solitaire_engine/src/touch_selection_plugin.rs

@@ -100,7 +100,11 @@ impl Plugin for TouchSelectionPlugin {
                 update_touch_selection_highlight,
             )
                 .chain()
-                .after(GameMutation),
+                .after(GameMutation)
+                // Selection cleanup and highlight placement settle before
+                // the board painters repaint (and before resync's synthetic
+                // StateChanged / fan-frac's layout write land) (#143).
+                .before(crate::card_plugin::BoardVisuals),
         );
     }
 }

solitaire_engine/src/ui_glass.rs

@@ -0,0 +1,281 @@
+//! "Liquid glass" material for floating UI surfaces.
+//!
+//! Produces the translucent, light-catching treatment used by the floating
+//! touch tab bar (`hud_plugin::tab_bar`): a semi-transparent fill with a
+//! vertical sheen, a specular rim highlight around the border, and a soft
+//! drop shadow underneath. The table shows through the fill *sharp* — Bevy's
+//! UI pipeline has no backdrop-blur concept, so this module approximates
+//! frosted glass with layered gradients instead of sampling what's behind
+//! the node. That keeps it a plain `bevy_ui` bundle: no custom shaders, no
+//! extra render passes, and identical behaviour on desktop, Android, and
+//! WebGL2.
+//!
+//! # Swapping the treatment
+//!
+//! Layout code depends only on [`glass_surface`] and [`GLASS_BORDER_PX`].
+//! A future real-refraction material (e.g. a `UiMaterial` sampling a blurred
+//! render target) can replace this module's internals without touching any
+//! caller — that boundary is the reason this file exists separately from
+//! `hud_plugin/tab_bar.rs`.
+//!
+//! # Departure from the Terminal design system
+//!
+//! `ui_theme` documents HUD chrome as opaque "status-line" panels. The glass
+//! bar is a deliberate, user-approved exception for the floating touch tab
+//! bar only; do not reuse this material for modals or the top HUD band
+//! without a matching design decision.
+
+use bevy::prelude::*;
+use bevy::ui::{
+    BackgroundGradient, BorderGradient, BoxShadow, ColorStop, LinearGradient, ShadowStyle,
+};
+
+use crate::ui_theme::{BG_ELEVATED, BORDER_SUBTLE, BORDER_SUBTLE_HC};
+
+/// Border width every glass surface must reserve in its `Node::border` so
+/// the rim gradient has a strip to paint into.
+pub const GLASS_BORDER_PX: f32 = 1.0;
+
+/// Marker on every node that received [`glass_surface`]. The settings
+/// plugin's `update_glass_surfaces` retargets these when the player
+/// toggles reduce-transparency or high-contrast, swapping the gradients
+/// in place via [`glass_decorations`].
+#[derive(Component, Debug)]
+pub struct GlassSurface;
+
+/// Base fill at the *bottom* of the glass sheet — near-black at ~62%
+/// opacity so the felt and cards remain visible through the bar while
+/// keeping icon/label contrast comfortable.
+const GLASS_FILL_BOTTOM: Color = Color::srgba(0.055, 0.055, 0.063, 0.62);
+
+/// Fill at the *top* of the sheet — the same glass lifted towards white,
+/// reading as the curved surface catching overhead light.
+const GLASS_FILL_TOP: Color = Color::srgba(0.20, 0.21, 0.23, 0.66);
+
+/// Rim highlight at the top edge — the bright specular line where a real
+/// glass pill would catch the light source.
+const GLASS_RIM_TOP: Color = Color::srgba(1.0, 1.0, 1.0, 0.38);
+
+/// Rim at the midpoint — almost gone, so the highlight reads as a glint
+/// rather than a drawn outline.
+const GLASS_RIM_MID: Color = Color::srgba(1.0, 1.0, 1.0, 0.06);
+
+/// Rim at the bottom edge — a faint secondary catch-light, as on the
+/// underside of a curved surface above a bright table.
+const GLASS_RIM_BOTTOM: Color = Color::srgba(1.0, 1.0, 1.0, 0.16);
+
+/// Drop shadow under the floating surface.
+const GLASS_SHADOW: Color = Color::srgba(0.0, 0.0, 0.0, 0.35);
+
+/// High-contrast fill — same glass, far less see-through, so text and
+/// icons keep contrast over any card art. Per `design-system.md`
+/// §Accessibility the HC toggle trades aesthetics for legibility.
+const GLASS_FILL_TOP_HC: Color = Color::srgba(0.20, 0.21, 0.23, 0.90);
+/// High-contrast fill at the bottom of the sheet.
+const GLASS_FILL_BOTTOM_HC: Color = Color::srgba(0.055, 0.055, 0.063, 0.88);
+
+/// High-contrast rim at the top edge — matches the luminance of
+/// `BORDER_SUBTLE_HC` so the bar's outline reads as strongly as every
+/// other HC-boosted border.
+const GLASS_RIM_TOP_HC: Color = Color::srgba(1.0, 1.0, 1.0, 0.75);
+/// High-contrast rim at the midpoint.
+const GLASS_RIM_MID_HC: Color = Color::srgba(1.0, 1.0, 1.0, 0.35);
+/// High-contrast rim at the bottom edge.
+const GLASS_RIM_BOTTOM_HC: Color = Color::srgba(1.0, 1.0, 1.0, 0.50);
+
+/// Visual components for a floating glass surface.
+///
+/// The caller owns the `Node` and must set two fields for the material to
+/// render correctly:
+/// - `border: UiRect::all(Val::Px(GLASS_BORDER_PX))` — the rim gradient
+///   paints into the border strip and is invisible without it.
+/// - `border_radius` — half the node height for a fully-round pill.
+///
+/// Everything here is fragment-shader work inside Bevy's stock UI pipeline,
+/// so it is safe on WebGL2 and adds no per-frame cost beyond ordinary nodes.
+pub fn glass_surface() -> impl Bundle {
+    let (sheen, rim) = glass_decorations(false, false);
+    (
+        GlassSurface,
+        sheen,
+        rim,
+        // Soft shadow underneath sells the "floating above the table" read.
+        BoxShadow(vec![ShadowStyle {
+            color: GLASS_SHADOW,
+            x_offset: Val::Px(0.0),
+            y_offset: Val::Px(6.0),
+            spread_radius: Val::Px(0.0),
+            blur_radius: Val::Px(16.0),
+        }]),
+    )
+}
+
+/// The sheen + rim pair for the requested accessibility state. The
+/// settings plugin overwrites every [`GlassSurface`]'s components with
+/// these when the relevant toggles change.
+///
+/// - Default: translucent fill with a top-lit sheen and a specular rim.
+/// - `high_contrast`: same shape, near-opaque fill, and a rim boosted to
+///   `BORDER_SUBTLE_HC` luminance so the outline stays legible.
+/// - `reduce_transparency`: flat opaque `BG_ELEVATED` fill and a flat
+///   border — no see-through at all. Combined with `high_contrast` the
+///   flat border brightens to `BORDER_SUBTLE_HC`.
+pub fn glass_decorations(
+    reduce_transparency: bool,
+    high_contrast: bool,
+) -> (BackgroundGradient, BorderGradient) {
+    if reduce_transparency {
+        // "Gradients" with a single stop render as flat fills — reusing the
+        // same component types means the settings toggle swaps values, not
+        // component sets.
+        let border = if high_contrast {
+            BORDER_SUBTLE_HC
+        } else {
+            BORDER_SUBTLE
+        };
+        return (
+            BackgroundGradient(vec![
+                LinearGradient::new(
+                    LinearGradient::TO_BOTTOM,
+                    vec![ColorStop::new(BG_ELEVATED, Val::Percent(0.0))],
+                )
+                .into(),
+            ]),
+            BorderGradient(vec![
+                LinearGradient::new(
+                    LinearGradient::TO_BOTTOM,
+                    vec![ColorStop::new(border, Val::Percent(0.0))],
+                )
+                .into(),
+            ]),
+        );
+    }
+
+    let (fill_top, fill_bottom, rim_top, rim_mid, rim_bottom) = if high_contrast {
+        (
+            GLASS_FILL_TOP_HC,
+            GLASS_FILL_BOTTOM_HC,
+            GLASS_RIM_TOP_HC,
+            GLASS_RIM_MID_HC,
+            GLASS_RIM_BOTTOM_HC,
+        )
+    } else {
+        (
+            GLASS_FILL_TOP,
+            GLASS_FILL_BOTTOM,
+            GLASS_RIM_TOP,
+            GLASS_RIM_MID,
+            GLASS_RIM_BOTTOM,
+        )
+    };
+    (
+        // Sheen: one top-to-bottom linear gradient carries both the fill and
+        // the lighting so there is a single source of truth for the surface
+        // colour (a separate `BackgroundColor` would just be painted over).
+        BackgroundGradient(vec![
+            LinearGradient::new(
+                LinearGradient::TO_BOTTOM,
+                vec![
+                    ColorStop::new(fill_top, Val::Percent(0.0)),
+                    ColorStop::new(fill_bottom, Val::Percent(60.0)),
+                ],
+            )
+            .into(),
+        ]),
+        // Specular rim: bright at the top edge, fading out through the
+        // sides, with a faint return at the bottom.
+        BorderGradient(vec![
+            LinearGradient::new(
+                LinearGradient::TO_BOTTOM,
+                vec![
+                    ColorStop::new(rim_top, Val::Percent(0.0)),
+                    ColorStop::new(rim_mid, Val::Percent(55.0)),
+                    ColorStop::new(rim_bottom, Val::Percent(100.0)),
+                ],
+            )
+            .into(),
+        ]),
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use bevy::ui::Gradient;
+
+    /// The bundle must insert all three visual components — a regression
+    /// here (e.g. a refactor dropping the rim) would silently flatten the
+    /// glass into a plain translucent box.
+    #[test]
+    fn glass_surface_inserts_sheen_rim_and_shadow() {
+        let mut world = World::new();
+        let e = world.spawn(glass_surface()).id();
+        assert!(world.get::<BackgroundGradient>(e).is_some());
+        assert!(world.get::<BorderGradient>(e).is_some());
+        assert!(world.get::<BoxShadow>(e).is_some());
+    }
+
+    /// The fill must stay translucent (that is the whole point of glass) but
+    /// opaque enough that text keeps contrast over busy card art.
+    #[test]
+    fn glass_fill_alpha_stays_in_readable_band() {
+        for fill in [GLASS_FILL_TOP, GLASS_FILL_BOTTOM] {
+            let a = fill.alpha();
+            assert!(
+                (0.4..=0.85).contains(&a),
+                "glass fill alpha {a} outside readable 0.4–0.85 band"
+            );
+        }
+    }
+
+    /// The rim gradient must actually glint: strictly brightest at the top,
+    /// dimmest in the middle.
+    #[test]
+    fn rim_highlight_peaks_at_top() {
+        assert!(GLASS_RIM_TOP.alpha() > GLASS_RIM_BOTTOM.alpha());
+        assert!(GLASS_RIM_BOTTOM.alpha() > GLASS_RIM_MID.alpha());
+        assert!(GLASS_RIM_TOP_HC.alpha() > GLASS_RIM_BOTTOM_HC.alpha());
+        assert!(GLASS_RIM_BOTTOM_HC.alpha() > GLASS_RIM_MID_HC.alpha());
+    }
+
+    /// Reduce-transparency must produce fully opaque fills — the entire
+    /// point of the toggle is that nothing shows through.
+    #[test]
+    fn reduce_transparency_is_fully_opaque() {
+        for high_contrast in [false, true] {
+            let (sheen, _) = glass_decorations(true, high_contrast);
+            for gradient in &sheen.0 {
+                let Gradient::Linear(linear) = gradient else {
+                    panic!("reduce-transparency sheen must stay linear");
+                };
+                for stop in &linear.stops {
+                    assert_eq!(
+                        stop.color.alpha(),
+                        1.0,
+                        "opaque variant leaked translucency (hc={high_contrast})"
+                    );
+                }
+            }
+        }
+    }
+
+    /// High-contrast glass must be meaningfully less transparent than the
+    /// default, and its rim meaningfully brighter — otherwise the toggle
+    /// does nothing perceptible on this surface.
+    #[test]
+    fn high_contrast_boosts_fill_and_rim() {
+        assert!(GLASS_FILL_TOP_HC.alpha() >= GLASS_FILL_TOP.alpha() + 0.15);
+        assert!(GLASS_FILL_BOTTOM_HC.alpha() >= GLASS_FILL_BOTTOM.alpha() + 0.15);
+        assert!(GLASS_RIM_TOP_HC.alpha() >= GLASS_RIM_TOP.alpha() + 0.25);
+    }
+
+    /// `glass_surface()` must carry the marker the settings applier
+    /// retargets — without it the accessibility toggles silently skip
+    /// the bar.
+    #[test]
+    fn glass_surface_carries_retarget_marker() {
+        let mut world = World::new();
+        let e = world.spawn(glass_surface()).id();
+        assert!(world.get::<GlassSurface>(e).is_some());
+    }
+}

solitaire_engine/src/ui_modal.rs

@@ -60,9 +60,9 @@ use crate::settings_plugin::SettingsResource;
 use crate::ui_theme::{
     ACCENT_PRIMARY, ACCENT_PRIMARY_HOVER, ACCENT_SECONDARY, BG_BASE, BG_ELEVATED, BG_ELEVATED_HI,
     BG_ELEVATED_PRESSED, BG_ELEVATED_TOP, BORDER_STRONG, BORDER_SUBTLE, HighContrastBorder,
-    MOTION_MODAL_SECS, RADIUS_LG, RADIUS_MD, RADIUS_SM, SCRIM, STATE_SUCCESS, TEXT_PRIMARY,
-    TEXT_SECONDARY, TYPE_BODY_LG, TYPE_CAPTION, TYPE_HEADLINE, VAL_SPACE_2, VAL_SPACE_3,
-    VAL_SPACE_4, VAL_SPACE_5, scaled_duration,
+    MOTION_MODAL_SECS, RADIUS_LG, RADIUS_MD, RADIUS_SM, SCRIM, STATE_SUCCESS, TEXT_DISABLED,
+    TEXT_PRIMARY, TEXT_SECONDARY, TYPE_BODY, TYPE_BODY_LG, TYPE_CAPTION, TYPE_DISPLAY,
+    TYPE_HEADLINE, VAL_SPACE_2, VAL_SPACE_3, VAL_SPACE_4, VAL_SPACE_5, scaled_duration,
 };
 
 // ---------------------------------------------------------------------------
@@ -328,6 +328,80 @@ pub fn spawn_modal_body_text(
     parent.spawn((ModalBody, Text::new(text.into()), font, TextColor(color)));
 }
 
+/// Standard empty / loading / error surface (Phase L): a large glyph,
+/// a headline, and an optional secondary detail line, centred in the
+/// available space. Every async or possibly-empty surface (leaderboard,
+/// replays, theme store, first-launch stats) renders through this so
+/// "nothing here yet" reads identically everywhere.
+///
+/// A next-step action is composition, not configuration: spawn a
+/// [`spawn_modal_button`] (or any control) in the same parent right
+/// after this call.
+///
+/// `glyph` MUST come from FiraMono-covered ranges — card suits
+/// (U+2660–2666), Arrows (U+2190–21FF), or ASCII. The Geometric Shapes
+/// block renders as tofu on Android (§10 / §11).
+pub fn spawn_empty_state(
+    parent: &mut ChildSpawnerCommands,
+    glyph: &str,
+    headline: &str,
+    detail: Option<&str>,
+    font_res: Option<&FontResource>,
+) {
+    let font_handle = font_res.map(|f| f.0.clone()).unwrap_or_default();
+    let font_glyph = TextFont {
+        font: font_handle.clone(),
+        font_size: TYPE_DISPLAY,
+        ..default()
+    };
+    let font_headline = TextFont {
+        font: font_handle.clone(),
+        font_size: TYPE_BODY_LG,
+        ..default()
+    };
+    let font_detail = TextFont {
+        font: font_handle,
+        font_size: TYPE_BODY,
+        ..default()
+    };
+
+    parent
+        .spawn((
+            EmptyStateBlock,
+            Node {
+                flex_direction: FlexDirection::Column,
+                align_items: AlignItems::Center,
+                row_gap: VAL_SPACE_2,
+                padding: UiRect::axes(VAL_SPACE_3, VAL_SPACE_5),
+                width: Val::Percent(100.0),
+                ..default()
+            },
+        ))
+        .with_children(|block| {
+            block.spawn((
+                Text::new(glyph.to_string()),
+                font_glyph,
+                TextColor(TEXT_DISABLED),
+            ));
+            block.spawn((
+                Text::new(headline.to_string()),
+                font_headline,
+                TextColor(TEXT_PRIMARY),
+            ));
+            if let Some(detail) = detail {
+                block.spawn((
+                    Text::new(detail.to_string()),
+                    font_detail,
+                    TextColor(TEXT_SECONDARY),
+                ));
+            }
+        });
+}
+
+/// Marker on every [`spawn_empty_state`] block, mostly for tests.
+#[derive(Component, Debug)]
+pub struct EmptyStateBlock;
+
 /// Spawns the bottom actions row — flex-row with primary right-aligned.
 /// The closure populates the row's buttons via `spawn_modal_button`.
 ///
@@ -472,6 +546,15 @@ pub fn spawn_tab_chip<M: Component>(
 // Generic touch-scroll helper
 // ---------------------------------------------------------------------------
 
+/// Self-ambiguous writer set for the per-modal scroll systems (mouse-wheel
+/// and touch variants). Every member writes `ScrollPosition`, but each
+/// targets only its own modal's scrollable body via a marker component, and
+/// the modal-stacking guard means at most one such panel exists at a time —
+/// the writes are disjoint by design, so members declare
+/// `.in_set(PanelScroll).ambiguous_with(PanelScroll)` (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PanelScroll;
+
 /// Scrolls any `Overflow::scroll_y()` panel marked with `M` via single-finger
 /// touch pan. Add this as a system for each scrollable modal panel:
 ///
@@ -766,7 +849,11 @@ impl Plugin for UiModalPlugin {
                 .in_set(crate::ui_theme::UiTextFx)
                 .ambiguous_with(crate::ui_theme::UiTextFx)
                 .ambiguous_with(crate::card_plugin::BoardVisuals)
-                .ambiguous_with(crate::hud_plugin::HudButtons),
+                .ambiguous_with(crate::hud_plugin::HudButtons)
+                // Reads only the anim-speed settings field — disjoint from
+                // the screen-plugin club's writes (#143).
+                .in_set(crate::settings_plugin::SettingsAccess)
+                .ambiguous_with(crate::settings_plugin::SettingsAccess),
         );
         // Click-outside-to-dismiss is independent of the open
         // animation chain — it reads `just_pressed(Left)` and runs
@@ -1184,4 +1271,62 @@ mod tests {
             "exactly one of the two stacked dismissible modals should remain"
         );
     }
+
+    // -----------------------------------------------------------------------
+    // Phase L: standard empty state
+    // -----------------------------------------------------------------------
+
+    /// The helper spawns glyph + headline (+ detail when given) under one
+    /// marked block, so every empty surface renders identically.
+    #[test]
+    fn empty_state_spawns_expected_structure() {
+        let mut app = App::new();
+        app.add_plugins(MinimalPlugins);
+        {
+            let world = app.world_mut();
+            let mut commands = world.commands();
+            commands.spawn(Node::default()).with_children(|parent| {
+                spawn_empty_state(
+                    parent,
+                    "\u{2660}",
+                    "Nothing here.",
+                    Some("Do the thing."),
+                    None,
+                );
+                spawn_empty_state(parent, "!", "No detail variant.", None, None);
+            });
+        }
+        app.update();
+
+        let blocks = app
+            .world_mut()
+            .query_filtered::<Entity, With<EmptyStateBlock>>()
+            .iter(app.world())
+            .count();
+        assert_eq!(blocks, 2, "each call spawns exactly one marked block");
+
+        let texts: Vec<String> = app
+            .world_mut()
+            .query::<&Text>()
+            .iter(app.world())
+            .map(|t| t.0.clone())
+            .collect();
+        for expected in [
+            "\u{2660}",
+            "Nothing here.",
+            "Do the thing.",
+            "!",
+            "No detail variant.",
+        ] {
+            assert!(
+                texts.iter().any(|t| t == expected),
+                "missing text node {expected:?}; got {texts:?}"
+            );
+        }
+        assert_eq!(
+            texts.len(),
+            5,
+            "the detail-less variant must not spawn a detail node"
+        );
+    }
 }

solitaire_engine/src/ui_tooltip.rs

@@ -93,7 +93,23 @@ impl Plugin for UiTooltipPlugin {
     fn build(&self, app: &mut App) {
         app.init_resource::<TooltipState>()
             .add_systems(Startup, spawn_tooltip_overlay)
-            .add_systems(Update, (track_tooltip_hover, show_or_hide_tooltip).chain());
+            // The tooltip pair only touches the tooltip overlay entity and
+            // reads settings for the enable flag — chrome-disjoint from the
+            // other UiTextFx members, and a settings read that may lag a
+            // frame joins the SettingsAccess club (#143).
+            .add_systems(
+                Update,
+                (track_tooltip_hover, show_or_hide_tooltip)
+                    .chain()
+                    .in_set(crate::ui_theme::UiTextFx)
+                    .ambiguous_with(crate::ui_theme::UiTextFx)
+                    .in_set(crate::settings_plugin::SettingsAccess)
+                    .ambiguous_with(crate::settings_plugin::SettingsAccess)
+                    // The tooltip node is neither a board entity nor a pile
+                    // marker; the visibility writes can't collide (#143).
+                    .ambiguous_with(crate::card_plugin::BoardVisuals)
+                    .ambiguous_with(crate::table_plugin::MarkerVisuals),
+            );
     }
 }
 

solitaire_engine/src/weekly_goals_plugin.rs

@@ -10,8 +10,8 @@ use solitaire_data::{
 };
 
 use crate::events::{GameWonEvent, XpAwardedEvent};
-use crate::game_plugin::GameMutation;
-use crate::progress_plugin::{LevelUpEvent, ProgressResource, ProgressStoragePath, ProgressUpdate};
+
+use crate::progress_plugin::{LevelUpEvent, ProgressResource, ProgressStoragePath};
 use crate::resources::GameStateResource;
 
 /// Fired when the player has just completed a weekly goal.
@@ -33,11 +33,11 @@ impl Plugin for WeeklyGoalsPlugin {
             .add_systems(Startup, roll_weekly_goals_on_startup)
             // Run after GameMutation (so GameWonEvent is available) and
             // ProgressUpdate (so we don't fight ProgressPlugin's add_xp).
+            // Ordering comes from the mode-completion chain configured in
+            // progress_plugin (#143).
             .add_systems(
                 Update,
-                evaluate_weekly_goals
-                    .after(GameMutation)
-                    .after(ProgressUpdate),
+                evaluate_weekly_goals.in_set(crate::progress_plugin::WeeklyGoalsEval),
             );
     }
 }

solitaire_engine/src/whats_new_plugin.rs

@@ -0,0 +1,527 @@
+//! One-shot "What's new" card on the first launch after an update
+//! (Phase I of the 2026-07 UI redesign).
+//!
+//! ObtainX updates install silently, so shipped features go unnoticed —
+//! nobody found the theme store on their own. On the first launch where
+//! the running release differs from `Settings::last_seen_whats_new`,
+//! this plugin shows a single dismissible card summarising the latest
+//! changelog section, then records the version so the card never
+//! repeats. Fresh installs never see it: onboarding completion stamps
+//! the current version silently, so the card only ever describes an
+//! *upgrade*.
+//!
+//! # Launch beat
+//!
+//! Splash → (first run only: onboarding) → **what's new** → Home →
+//! table. `spawn_home_on_launch` waits on [`WhatsNewPending`] the same
+//! way it waits for the onboarding modal.
+//!
+//! # Version source
+//!
+//! The embedded `CHANGELOG.md`'s topmost release section provides both
+//! the card's content and the "current version" for change detection —
+//! one source of truth, no build-time version plumbing. (The APK
+//! `versionName` comes from the release tag at package time and never
+//! reaches Rust; the workspace `Cargo.toml` version is static.)
+
+use bevy::input::ButtonInput;
+use bevy::prelude::*;
+use solitaire_data::save_settings_to;
+
+use crate::font_plugin::FontResource;
+use crate::onboarding_plugin::OnboardingScreen;
+use crate::settings_plugin::{SettingsResource, SettingsStoragePath};
+use crate::ui_modal::{
+    ButtonVariant, ModalScrim, spawn_modal, spawn_modal_actions, spawn_modal_button,
+    spawn_modal_header,
+};
+use crate::ui_theme::{
+    TEXT_PRIMARY, TEXT_SECONDARY, TYPE_BODY, TYPE_CAPTION, VAL_SPACE_1, VAL_SPACE_2, Z_MODAL_PANEL,
+};
+
+/// The changelog ships inside the binary — small, changes only at
+/// release cadence, and the card must work offline (§4.2).
+const CHANGELOG: &str = include_str!("../../CHANGELOG.md");
+
+/// Most bullets shown on the card; a giant release stays skimmable.
+const MAX_CARD_BULLETS: usize = 8;
+
+/// Marker on the What's-new modal's scrim root.
+#[derive(Component, Debug)]
+pub struct WhatsNewScreen;
+
+/// Marker on the card's "Got it" button.
+#[derive(Component, Debug)]
+struct WhatsNewCloseButton;
+
+/// `true` until this plugin has made its launch-beat decision — either
+/// the card was shown and dismissed, or there was nothing to show.
+/// `spawn_home_on_launch` waits on this so the card gets the beat
+/// before Home.
+#[derive(Resource, Debug)]
+pub struct WhatsNewPending(pub bool);
+
+impl Default for WhatsNewPending {
+    fn default() -> Self {
+        Self(true)
+    }
+}
+
+/// One display line of the card.
+#[derive(Debug, PartialEq, Eq)]
+enum NoteLine {
+    /// A `###` section heading ("Added", "Fixed", …).
+    Heading(String),
+    /// The lead sentence of one changelog bullet.
+    Bullet(String),
+}
+
+/// The changelog's topmost release section, reduced to card content.
+#[derive(Debug)]
+struct ReleaseNotes {
+    /// Version string without the `v` prefix, e.g. `"0.46.0"`.
+    version: String,
+    lines: Vec<NoteLine>,
+}
+
+/// The version of the topmost changelog release — the engine's notion
+/// of "the running release". Empty only if the changelog is malformed.
+pub fn current_release_version() -> String {
+    parse_latest_release(CHANGELOG).map_or_else(String::new, |notes| notes.version)
+}
+
+/// Parses the first `## [x.y.z]` section of `changelog` into card
+/// content. `## [Unreleased]` is skipped; `### Internal` subsections
+/// are dropped (players don't care about CI); each bullet is reduced
+/// to its lead sentence with markdown emphasis stripped.
+fn parse_latest_release(changelog: &str) -> Option<ReleaseNotes> {
+    let mut lines_iter = changelog.lines();
+    let mut version = None;
+    for line in lines_iter.by_ref() {
+        if let Some(rest) = line.strip_prefix("## [") {
+            let (v, _) = rest.split_once(']')?;
+            if v.eq_ignore_ascii_case("Unreleased") {
+                continue;
+            }
+            version = Some(v.to_string());
+            break;
+        }
+    }
+    let version = version?;
+
+    let mut lines = Vec::new();
+    let mut skipping_section = false;
+    let mut current_bullet: Option<String> = None;
+
+    let flush = |bullet: &mut Option<String>, lines: &mut Vec<NoteLine>| {
+        if let Some(text) = bullet.take() {
+            lines.push(NoteLine::Bullet(lead_sentence(&text)));
+        }
+    };
+
+    for line in lines_iter {
+        if line.starts_with("## [") {
+            break; // next (older) release section
+        }
+        if let Some(heading) = line.strip_prefix("### ") {
+            flush(&mut current_bullet, &mut lines);
+            skipping_section = heading.trim().eq_ignore_ascii_case("internal");
+            if !skipping_section {
+                lines.push(NoteLine::Heading(heading.trim().to_string()));
+            }
+            continue;
+        }
+        if skipping_section {
+            continue;
+        }
+        if let Some(rest) = line.strip_prefix("- ") {
+            flush(&mut current_bullet, &mut lines);
+            current_bullet = Some(rest.trim().to_string());
+        } else if current_bullet.is_some() && !line.trim().is_empty() {
+            // Wrapped continuation of the current bullet.
+            if let Some(bullet) = current_bullet.as_mut() {
+                bullet.push(' ');
+                bullet.push_str(line.trim());
+            }
+        }
+    }
+    flush(&mut current_bullet, &mut lines);
+
+    Some(ReleaseNotes { version, lines })
+}
+
+/// Strips markdown emphasis / code ticks and truncates to the first
+/// sentence — changelog bullets lead with a bold summary sentence, and
+/// that is exactly the card-sized version.
+fn lead_sentence(bullet: &str) -> String {
+    let stripped: String = bullet.replace("**", "").replace('`', "");
+    // Trailing "(#123)" references never survive the sentence cut, but
+    // guard against a bullet that is only a reference.
+    let end = stripped.find(". ").map_or(stripped.len(), |i| i + 1);
+    stripped[..end].trim().trim_end_matches('.').to_string()
+}
+
+/// Registers the launch-gate spawn system and the dismiss handlers.
+pub struct WhatsNewPlugin;
+
+impl Plugin for WhatsNewPlugin {
+    fn build(&self, app: &mut App) {
+        app.init_resource::<WhatsNewPending>()
+            .init_resource::<ButtonInput<KeyCode>>()
+            .add_systems(
+                Update,
+                (maybe_spawn_whats_new, handle_whats_new_close).chain(),
+            );
+    }
+}
+
+/// Shows the card once the launch surface is clear, or stands down when
+/// there is nothing to show. See the module docs for the exact beat.
+///
+/// The seen-version stamp persists on *spawn*, not dismissal — if the
+/// app dies with the card open the player has still seen it once, and
+/// the card must never nag.
+#[allow(clippy::too_many_arguments)]
+fn maybe_spawn_whats_new(
+    mut commands: Commands,
+    mut pending: ResMut<WhatsNewPending>,
+    splash: Query<(), With<crate::splash_plugin::SplashRoot>>,
+    onboarding: Query<(), With<OnboardingScreen>>,
+    restore_prompts: Query<(), With<crate::game_plugin::RestorePromptScreen>>,
+    pending_restore: Option<Res<crate::game_plugin::PendingRestoredGame>>,
+    other_scrims: Query<(), With<ModalScrim>>,
+    mut settings: Option<ResMut<SettingsResource>>,
+    storage_path: Option<Res<SettingsStoragePath>>,
+    font_res: Option<Res<FontResource>>,
+    screens: Query<(), With<WhatsNewScreen>>,
+) {
+    if !pending.0 {
+        return;
+    }
+    if !screens.is_empty() {
+        // Card already open — the seen-version stamp landed on spawn,
+        // so without this guard the next frame would read "already
+        // seen" and release the beat under the open card.
+        return;
+    }
+    if !splash.is_empty()
+        || !onboarding.is_empty()
+        || !restore_prompts.is_empty()
+        || pending_restore.as_ref().is_some_and(|p| p.0.is_some())
+    {
+        return;
+    }
+    let Some(settings) = settings.as_mut() else {
+        // Headless / no settings wired: nothing to compare against.
+        pending.0 = false;
+        return;
+    };
+    if !settings.0.first_run_complete {
+        // Fresh install mid-onboarding — completion stamps the version
+        // itself (see `complete_onboarding`), which resolves this gate
+        // on a later frame without ever showing the card.
+        return;
+    }
+    let Some(notes) = parse_latest_release(CHANGELOG) else {
+        pending.0 = false;
+        return;
+    };
+    if settings.0.last_seen_whats_new == notes.version {
+        pending.0 = false;
+        return;
+    }
+    if !other_scrims.is_empty() {
+        // Another modal owns the beat right now; try again next frame.
+        return;
+    }
+
+    spawn_whats_new_card(&mut commands, &notes, font_res.as_deref());
+
+    settings.0.last_seen_whats_new = notes.version.clone();
+    if let Some(p) = storage_path
+        && let Some(path) = p.0.as_deref()
+        && let Err(e) = save_settings_to(path, &settings.0)
+    {
+        warn!("whats-new: failed to persist seen version: {e}");
+    }
+    // `pending` stays true until dismissal so Home keeps waiting.
+}
+
+/// Dismisses the card on "Got it" or Esc and releases the launch beat.
+fn handle_whats_new_close(
+    mut commands: Commands,
+    keys: Option<Res<ButtonInput<KeyCode>>>,
+    buttons: Query<&Interaction, (With<WhatsNewCloseButton>, Changed<Interaction>)>,
+    screens: Query<Entity, With<WhatsNewScreen>>,
+    other_scrims: Query<(), (With<ModalScrim>, Without<WhatsNewScreen>)>,
+    mut pending: ResMut<WhatsNewPending>,
+) {
+    if screens.is_empty() {
+        return;
+    }
+    let click = buttons.iter().any(|i| *i == Interaction::Pressed);
+    let esc = keys.is_some_and(|k| k.just_pressed(KeyCode::Escape)) && other_scrims.is_empty();
+    if !click && !esc {
+        return;
+    }
+    for entity in &screens {
+        commands.entity(entity).despawn();
+    }
+    pending.0 = false;
+}
+
+/// Spawns the card: header with the version, the parsed changelog
+/// lines, and a "Got it" action.
+fn spawn_whats_new_card(
+    commands: &mut Commands,
+    notes: &ReleaseNotes,
+    font_res: Option<&FontResource>,
+) {
+    let font_handle = font_res.map(|f| f.0.clone()).unwrap_or_default();
+    let font_heading = TextFont {
+        font: font_handle.clone(),
+        font_size: TYPE_CAPTION,
+        ..default()
+    };
+    let font_bullet = TextFont {
+        font: font_handle,
+        font_size: TYPE_BODY,
+        ..default()
+    };
+
+    // Deliberately NOT ScrimDismissible: scrim-tap despawns without
+    // running the close handler, which would leave the launch beat
+    // held and Home never spawning. Esc and "Got it" both release it.
+    let title = format!("What's new in v{}", notes.version);
+    spawn_modal(commands, WhatsNewScreen, Z_MODAL_PANEL, |card| {
+        spawn_modal_header(card, &title, font_res);
+
+        card.spawn(Node {
+            flex_direction: FlexDirection::Column,
+            row_gap: VAL_SPACE_2,
+            width: Val::Percent(100.0),
+            max_height: Val::Vh(60.0),
+            overflow: Overflow::scroll_y(),
+            ..default()
+        })
+        .with_children(|body| {
+            let mut bullets_shown = 0usize;
+            for line in &notes.lines {
+                match line {
+                    NoteLine::Heading(heading) => {
+                        body.spawn((
+                            Text::new(heading.clone()),
+                            font_heading.clone(),
+                            TextColor(TEXT_SECONDARY),
+                            Node {
+                                margin: UiRect::top(VAL_SPACE_1),
+                                ..default()
+                            },
+                        ));
+                    }
+                    NoteLine::Bullet(text) => {
+                        if bullets_shown >= MAX_CARD_BULLETS {
+                            continue;
+                        }
+                        bullets_shown += 1;
+                        body.spawn((
+                            Text::new(format!("\u{2022} {text}")),
+                            font_bullet.clone(),
+                            TextColor(TEXT_PRIMARY),
+                        ));
+                    }
+                }
+            }
+        });
+
+        spawn_modal_actions(card, |actions| {
+            spawn_modal_button(
+                actions,
+                WhatsNewCloseButton,
+                "Got it",
+                None,
+                ButtonVariant::Primary,
+                font_res,
+            );
+        });
+    });
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use solitaire_data::Settings;
+
+    const SAMPLE: &str = "# Changelog\n\n## [Unreleased]\n\n## [0.46.0] — 2026-07-13\n\n\
+### Added\n\n- **Theme-store previews.** The store modal now shows each theme's\n  \
+preview image next to its name. (#179)\n- **Hint ghost preview.** You see the move. (#179)\n\n\
+### Internal\n\n- **CI is faster.** Nobody cares in-game. (#176)\n\n\
+### Fixed\n\n- **Touch onboarding copy.** No more left-click. (#178)\n\n\
+## [0.45.0] — 2026-07-13\n\n### Added\n\n- Old stuff.\n";
+
+    #[test]
+    fn parses_top_section_version_and_skips_unreleased() {
+        let notes = parse_latest_release(SAMPLE).expect("sample must parse");
+        assert_eq!(notes.version, "0.46.0");
+    }
+
+    #[test]
+    fn drops_internal_sections_and_older_releases() {
+        let notes = parse_latest_release(SAMPLE).expect("sample must parse");
+        let headings: Vec<&str> = notes
+            .lines
+            .iter()
+            .filter_map(|l| match l {
+                NoteLine::Heading(h) => Some(h.as_str()),
+                _ => None,
+            })
+            .collect();
+        assert_eq!(headings, vec!["Added", "Fixed"]);
+        assert!(
+            !notes
+                .lines
+                .iter()
+                .any(|l| matches!(l, NoteLine::Bullet(b) if b.contains("CI is faster"))),
+            "Internal bullets must not reach the card"
+        );
+        assert!(
+            !notes
+                .lines
+                .iter()
+                .any(|l| matches!(l, NoteLine::Bullet(b) if b.contains("Old stuff"))),
+            "older release sections must not bleed in"
+        );
+    }
+
+    #[test]
+    fn bullets_reduce_to_their_lead_sentence() {
+        let notes = parse_latest_release(SAMPLE).expect("sample must parse");
+        assert!(
+            notes
+                .lines
+                .contains(&NoteLine::Bullet("Theme-store previews".to_string()))
+        );
+        assert!(
+            notes
+                .lines
+                .contains(&NoteLine::Bullet("Hint ghost preview".to_string()))
+        );
+    }
+
+    #[test]
+    fn embedded_changelog_parses_to_a_nonempty_version() {
+        let version = current_release_version();
+        assert!(
+            !version.is_empty(),
+            "the real CHANGELOG.md must yield a version"
+        );
+        assert!(
+            version.chars().next().is_some_and(|c| c.is_ascii_digit()),
+            "version must be bare (no v prefix): {version}"
+        );
+    }
+
+    fn app_with(settings: Settings) -> App {
+        let mut app = App::new();
+        app.add_plugins(MinimalPlugins).add_plugins(WhatsNewPlugin);
+        app.insert_resource(SettingsResource(settings));
+        app.update();
+        app
+    }
+
+    fn card_count(app: &mut App) -> usize {
+        app.world_mut()
+            .query::<&WhatsNewScreen>()
+            .iter(app.world())
+            .count()
+    }
+
+    #[test]
+    fn upgrade_shows_card_and_stamps_version() {
+        let mut app = app_with(Settings {
+            first_run_complete: true,
+            last_seen_whats_new: "0.1.0".into(),
+            ..Settings::default()
+        });
+        app.update();
+
+        assert_eq!(card_count(&mut app), 1, "an upgrade must show the card");
+        assert_eq!(
+            app.world()
+                .resource::<SettingsResource>()
+                .0
+                .last_seen_whats_new,
+            current_release_version(),
+            "the seen version must stamp on spawn"
+        );
+        assert!(
+            app.world().resource::<WhatsNewPending>().0,
+            "the launch beat stays held until dismissal"
+        );
+    }
+
+    #[test]
+    fn seen_version_shows_nothing_and_releases_the_beat() {
+        let mut app = app_with(Settings {
+            first_run_complete: true,
+            last_seen_whats_new: current_release_version(),
+            ..Settings::default()
+        });
+        app.update();
+
+        assert_eq!(card_count(&mut app), 0);
+        assert!(
+            !app.world().resource::<WhatsNewPending>().0,
+            "nothing to show must release the launch beat"
+        );
+    }
+
+    #[test]
+    fn fresh_install_waits_for_onboarding_and_never_shows() {
+        let mut app = app_with(Settings {
+            first_run_complete: false,
+            ..Settings::default()
+        });
+        app.update();
+        assert_eq!(card_count(&mut app), 0);
+        assert!(
+            app.world().resource::<WhatsNewPending>().0,
+            "mid-onboarding the beat stays held"
+        );
+
+        // Onboarding completion stamps the version (mirrored from
+        // complete_onboarding) — afterwards the card must stand down.
+        {
+            let mut settings = app.world_mut().resource_mut::<SettingsResource>();
+            settings.0.first_run_complete = true;
+            settings.0.last_seen_whats_new = current_release_version();
+        }
+        app.update();
+        assert_eq!(card_count(&mut app), 0, "fresh installs never see the card");
+        assert!(!app.world().resource::<WhatsNewPending>().0);
+    }
+
+    #[test]
+    fn got_it_dismisses_and_releases_the_beat() {
+        let mut app = app_with(Settings {
+            first_run_complete: true,
+            ..Settings::default()
+        });
+        app.update();
+        assert_eq!(card_count(&mut app), 1);
+
+        let button = app
+            .world_mut()
+            .query_filtered::<Entity, With<WhatsNewCloseButton>>()
+            .single(app.world())
+            .expect("Got it button must exist");
+        app.world_mut()
+            .entity_mut(button)
+            .insert(Interaction::Pressed);
+        app.update();
+        app.update();
+
+        assert_eq!(card_count(&mut app), 0, "Got it must dismiss the card");
+        assert!(!app.world().resource::<WhatsNewPending>().0);
+    }
+}

solitaire_engine/src/win_summary_plugin.rs

@@ -18,7 +18,7 @@
 //! shake duration elapses.
 
 use bevy::prelude::*;
-use solitaire_core::game_state::GameMode;
+use solitaire_core::game_state::{GameMode, GameState};
 use solitaire_core::scoring::compute_time_bonus;
 use solitaire_data::AnimSpeed;
 
@@ -93,6 +93,40 @@ pub struct WinSummaryPending {
     /// score-breakdown reveal can format the mode-multiplier row
     /// (e.g. `Zen ×0.0`, `Classic ×1.0`).
     pub mode: GameMode,
+    /// Per-move-type recap of the winning game, e.g.
+    /// `"21 to foundation · 14 tableau moves · 9 flips · 1 recycle"`.
+    /// Built from the upstream session counters at win time; empty when
+    /// every counter is zero (synthesised test wins).
+    pub move_detail: String,
+}
+
+/// Formats the per-move-type recap line for the win modal from the
+/// upstream session counters. Zero-valued components are omitted so the
+/// line stays short; returns an empty string when nothing was counted
+/// (only possible for synthesised test wins).
+fn build_move_detail(game: &GameState) -> String {
+    let mut parts: Vec<String> = Vec::new();
+    let foundation = game.move_to_foundation_count();
+    if foundation > 0 {
+        parts.push(format!("{foundation} to foundation"));
+    }
+    let tableau = game.move_to_tableau_count();
+    if tableau > 0 {
+        parts.push(format!("{tableau} tableau moves"));
+    }
+    let flips = game.flip_up_count();
+    if flips > 0 {
+        parts.push(format!("{flips} flips"));
+    }
+    let recycles = game.recycle_count();
+    if recycles > 0 {
+        parts.push(format!("{recycles} recycles"));
+    }
+    let returns = game.move_from_foundation_count();
+    if returns > 0 {
+        parts.push(format!("{returns} foundation returns"));
+    }
+    parts.join(" \u{00B7} ")
 }
 
 /// Builds a human-readable XP breakdown string for the win modal.
@@ -232,20 +266,54 @@ impl Plugin for WinSummaryPlugin {
             // the player's old personal-best values before `StatsPlugin` overwrites them.
             .add_systems(
                 Update,
-                cache_win_data.after(GameMutation).before(StatsUpdate),
+                cache_win_data
+                    .after(GameMutation)
+                    .before(StatsUpdate)
+                    // Must also read pre-award progress (old level for the
+                    // level-up row) and emits the personal-best toast.
+                    .before(crate::progress_plugin::ProgressUpdate)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
             )
             .add_systems(
                 Update,
+                // One deterministic chain, late on the frame: after AnimFx
+                // so the unlock/XP event streams it drains are settled by
+                // both achievement evaluators (win + replay-completion run
+                // before AnimFx). Members join the request/toast writer
+                // clubs they append to; the camera shake and the score
+                // reveal touch entity domains disjoint from the card/HUD
+                // painters (#143).
                 (
-                    collect_session_achievements,
-                    spawn_win_summary_after_delay,
-                    handle_win_summary_buttons,
+                    collect_session_achievements
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters),
+                    spawn_win_summary_after_delay
+                        .in_set(crate::settings_plugin::SettingsAccess)
+                        .ambiguous_with(crate::settings_plugin::SettingsAccess),
+                    handle_win_summary_buttons
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
                     close_overlay_on_watch_replay,
-                    handle_win_summary_keyboard,
-                    apply_screen_shake,
-                    reveal_score_breakdown,
+                    handle_win_summary_keyboard
+                        .in_set(crate::game_plugin::NewGameRequestWriters)
+                        .ambiguous_with(crate::game_plugin::NewGameRequestWriters)
+                        .before(crate::ui_focus::FocusKeys),
+                    apply_screen_shake
+                        .ambiguous_with(crate::feedback_anim_plugin::FeedbackFx)
+                        // Shakes the camera; hint ghosts are their own
+                        // entity domain (#143).
+                        .ambiguous_with(crate::feedback_anim_plugin::HintGhostFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
+                    reveal_score_breakdown
+                        .in_set(crate::ui_theme::UiTextFx)
+                        .ambiguous_with(crate::ui_theme::UiTextFx),
                 )
-                    .after(GameMutation),
+                    .chain()
+                    .after(GameMutation)
+                    .after(crate::animation_plugin::AnimFx),
             );
     }
 }
@@ -492,6 +560,7 @@ fn cache_win_data(
         pending.challenge_level = challenge_level;
         pending.undo_count = game.0.undo_count();
         pending.mode = game.0.mode;
+        pending.move_detail = build_move_detail(&game.0);
 
         if is_new_record {
             toast.write(InfoToastEvent("New Record!".to_string()));
@@ -913,6 +982,18 @@ fn spawn_overlay(
                     ));
                 }
 
+                // Move-type recap (same quiet styling as the XP breakdown)
+                if !pending.move_detail.is_empty() {
+                    card.spawn((
+                        Text::new(pending.move_detail.clone()),
+                        TextFont {
+                            font_size: 15.0,
+                            ..default()
+                        },
+                        TextColor(TEXT_SECONDARY),
+                    ));
+                }
+
                 // Achievements unlocked this game — at most 3 shown explicitly;
                 // excess is summarised with "...and N more".
                 if !session.names.is_empty() {
@@ -1288,6 +1369,49 @@ mod tests {
         assert_eq!(p.mode, GameMode::Classic);
     }
 
+    #[test]
+    fn build_move_detail_fresh_game_is_empty() {
+        let game = GameState::new(42, solitaire_core::DrawStockConfig::DrawOne);
+        assert!(
+            build_move_detail(&game).is_empty(),
+            "no moves yet, so the recap line must be empty"
+        );
+    }
+
+    #[test]
+    fn build_move_detail_reports_played_move_types() {
+        use solitaire_core::KlondikeInstruction;
+        // Drive a real deal forward so the upstream counters accumulate:
+        // prefer foundation moves, then anything else, drawing as needed.
+        let mut game = GameState::new(42, solitaire_core::DrawStockConfig::DrawOne);
+        for _ in 0..80 {
+            let instructions = game.possible_instructions();
+            let next = instructions
+                .iter()
+                .copied()
+                .find(|i| matches!(i, KlondikeInstruction::DstFoundation(_)))
+                .or_else(|| instructions.into_iter().next());
+            match next {
+                Some(i) => {
+                    let _ = game.apply_instruction(i);
+                }
+                None => break,
+            }
+            if game.move_to_foundation_count() > 0 && game.move_to_tableau_count() > 0 {
+                break;
+            }
+        }
+        let detail = build_move_detail(&game);
+        assert!(
+            detail.contains("to foundation"),
+            "seed 42 reaches a foundation move within 80 plies; got: {detail}"
+        );
+        assert!(
+            !detail.contains("0 "),
+            "zero-valued components must be omitted; got: {detail}"
+        );
+    }
+
     #[test]
     fn build_xp_detail_slow_win_with_undo() {
         // 300s >= 120s → no speed bonus; undo used → no no-undo bonus.

solitaire_server/Dockerfile

@@ -53,6 +53,10 @@ RUN cargo fetch --locked
 # src/) because solitaire_engine embeds theme/audio/font assets at compile
 # time from its own assets/ and the workspace assets/.
 COPY build_wasm.sh ./
+# whats_new_plugin embeds the changelog at compile time
+# (include_str!("../../CHANGELOG.md")) — omit it and the engine build
+# fails inside this stage while full-checkout builds stay green.
+COPY CHANGELOG.md ./
 COPY solitaire_core   ./solitaire_core
 COPY solitaire_sync   ./solitaire_sync
 COPY solitaire_data   ./solitaire_data

solitaire_server/web/replay.js

@@ -315,10 +315,9 @@ btnPlay.addEventListener("click", () => {
     }, STEP_INTERVAL_MS);
 });
 
-/// Step the player back one move. Re-creates the ReplayPlayer and fast-
-/// forwards to (step_idx - 1) without rendering intermediate frames, then
-/// renders once so the CSS transition animates each card to its previous
-/// position.
+/// Step the player back one move via the wasm-side seek (rewinds to the
+/// recorded deal and fast-forwards internally), then renders once so the
+/// CSS transition animates each card to its previous position.
 function stepBack() {
     if (!player || player.step_idx() === 0) return;
     if (playInterval) {
@@ -326,12 +325,7 @@ function stepBack() {
         playInterval = null;
         btnPlay.textContent = "▶ Play";
     }
-    const target = player.step_idx() - 1;
-    player = new ReplayPlayer(replayJson);
-    for (let i = 0; i < target; i++) {
-        player.step();
-    }
-    render(player.state());
+    render(player.seek(player.step_idx() - 1));
     btnPrev.disabled = player.step_idx() === 0;
     btnRestart.disabled = player.step_idx() === 0;
     btnStep.disabled = false;

solitaire_wasm/src/lib.rs

@@ -110,6 +110,9 @@ impl From<&(Card, bool)> for CardSnapshot {
 #[wasm_bindgen]
 pub struct ReplayPlayer {
     game: GameState,
+    /// The recorded deal before any instruction, kept so [`Self::seek_native`]
+    /// can rewind without reparsing the replay JSON.
+    initial: GameState,
     moves: Vec<KlondikeInstruction>,
     step_idx: usize,
 }
@@ -144,12 +147,30 @@ impl ReplayPlayer {
         // the current build maps seeds to deals.
         let (game, moves) = GameState::from_recording(&replay.recording, replay.seed, replay.mode);
         Ok(Self {
+            initial: game.clone(),
             game,
             moves,
             step_idx: 0,
         })
     }
 
+    /// Jump to `step` (clamped to the move count): the board state after
+    /// `step` moves have been applied. Rewinds by resetting to the stored
+    /// initial deal, then fast-forwards — a few hundred instruction
+    /// applications, microseconds in practice.
+    pub fn seek_native(&mut self, step: usize) -> Result<StateSnapshot, MoveError> {
+        let target = step.min(self.moves.len());
+        if target < self.step_idx {
+            self.game = self.initial.clone();
+            self.step_idx = 0;
+        }
+        while self.step_idx < target {
+            self.game.apply_instruction(self.moves[self.step_idx])?;
+            self.step_idx += 1;
+        }
+        Ok(self.snapshot())
+    }
+
     /// Apply the next move. Returns `Ok(None)` once the list is exhausted.
     pub fn step_native(&mut self) -> Result<Option<StateSnapshot>, MoveError> {
         if self.step_idx >= self.moves.len() {
@@ -236,6 +257,25 @@ impl ReplayPlayer {
         }
     }
 
+    /// Jump directly to `step` moves applied (clamped to the move count)
+    /// and return the snapshot there. Backwards seeks rewind to the
+    /// recorded deal and fast-forward, so any position is O(replay length)
+    /// at worst — no JSON reparse, no intermediate renders.
+    ///
+    /// Throws `"replay_desync"` if a recorded move is illegal during the
+    /// fast-forward (corrupt recording).
+    pub fn seek(&mut self, step: usize) -> Result<JsValue, JsValue> {
+        match self.seek_native(step) {
+            Ok(snap) => {
+                serde_wasm_bindgen::to_value(&snap).map_err(|e| JsValue::from_str(&e.to_string()))
+            }
+            Err(e) => {
+                log_replay_move_error(&e);
+                Err(JsValue::from_str("replay_desync"))
+            }
+        }
+    }
+
     /// Total number of moves the replay contains.
     pub fn total_steps(&self) -> usize {
         self.moves.len()
@@ -1062,6 +1102,57 @@ mod tests {
         assert_eq!(orig["stock"], repl["stock"], "stock deal must match");
     }
 
+    /// `seek` must land on exactly the state produced by stepping — both
+    /// forwards (fast-forward from the current position) and backwards
+    /// (rewind to the recorded deal, then fast-forward).
+    #[test]
+    fn seek_matches_stepping_in_both_directions() {
+        let mut game = SolitaireGame {
+            game: GameState::new_with_mode(51, DrawStockConfig::DrawOne, GameMode::Classic),
+        };
+        for _ in 0..24 {
+            let legal_moves = game.legal_moves_native();
+            if legal_moves.is_empty() {
+                break;
+            }
+            let idx = pick_move_index(&legal_moves).unwrap_or_default();
+            game.apply_legal_move_native(idx).expect("advance game");
+        }
+        let replay_json = game
+            .replay_export_native(60, "2026-07-10")
+            .expect("export replay");
+
+        let mut stepped = ReplayPlayer::from_json(&replay_json).expect("player A");
+        let mut seeker = ReplayPlayer::from_json(&replay_json).expect("player B");
+        let total = stepped.total_steps();
+        assert!(total >= 4, "test needs a few moves, got {total}");
+
+        // Forward: step A to k, seek B to k, compare snapshots.
+        let k = total / 2;
+        for _ in 0..k {
+            stepped.step_native().expect("step").expect("mid-replay");
+        }
+        let sought = seeker.seek_native(k).expect("seek forward");
+        assert_eq!(sought, stepped.snapshot(), "forward seek diverged at {k}");
+
+        // Backward: seek B to k - 2 and compare against a fresh stepper.
+        let back = k - 2;
+        let mut fresh = ReplayPlayer::from_json(&replay_json).expect("player C");
+        for _ in 0..back {
+            fresh.step_native().expect("step").expect("mid-replay");
+        }
+        let sought_back = seeker.seek_native(back).expect("seek backward");
+        assert_eq!(
+            sought_back,
+            fresh.snapshot(),
+            "backward seek diverged at {back}"
+        );
+
+        // Clamping: past-the-end seeks stop at the final state.
+        let end = seeker.seek_native(usize::MAX).expect("seek to end");
+        assert_eq!(end.step_idx, total);
+    }
+
     #[test]
     fn debug_api_autonomous_seed_batch_smoke() {
         for seed in 0_u64..128_u64 {