feat(replay): add HC bump for WIN MOVE scrub-bar marker; extend HighContrastBackground

HighContrastBackground gains an optional hc_color field so sites can
specify a domain-specific HC variant rather than always bumping to
BORDER_SUBTLE_HC (gray). with_default() fills hc_color = BORDER_SUBTLE_HC
preserving all existing behaviour; new with_hc(default, hc) lets callers
specify both ends. update_high_contrast_backgrounds reads marker.hc_color
instead of the hardcoded constant.

STATE_SUCCESS_HC (#c8e862, L≈0.73) added to ui_theme — a brighter lime
that maintains the success hue while standing out from bumped notch
ticks (BORDER_SUBTLE_HC gray, L≈0.60) under HC mode.

WIN MOVE marker now carries HighContrastBackground::with_hc(STATE_SUCCESS,
STATE_SUCCESS_HC): lime stays lime under HC instead of turning gray.
Unit test pins both the default and hc color fields on the spawned marker.

1276 tests pass / 0 failing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

CHANGELOG.md

@@ -6,9 +6,39 @@ project follows [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
-No threads in flight. v0.21.6 cut on 2026-05-08; CHANGELOG accumulates
+No threads in flight. v0.21.7 cut on 2026-05-08; CHANGELOG accumulates
 the next cycle here.
 
+## [0.21.7] — 2026-05-08
+
+Patch release closing the last major B-2 sub-piece. Through-line:
+**mini-tableau preview dim layer**. The mockup's "Game Peek Band at
+50 % opacity" is now implemented as a full-screen UI scrim that darkens
+the card world during replay so the chrome (banner + move-log panel)
+reads clearly against the scene.
+
+### Added
+
+- **Full-screen tableau dim layer** (`da3e542`). Spawns a
+  `ReplayTableauDimLayer` UI node (100 % × 100 %, 50 % opacity
+  black) at `Z_REPLAY_DIM = Z_REPLAY_OVERLAY − 1 = 54` whenever
+  a replay starts; despawned alongside the banner and move-log
+  panel when the replay ends. Bevy's UI/world compositor means
+  no changes to `card_plugin` are needed — UI nodes always
+  render above world-space sprites regardless of `Transform.z`.
+  The dim layer carries no `Interaction` component (purely
+  visual; pointer events pass through). Adds `Z_REPLAY_DIM`
+  and `TABLEAU_DIM_ALPHA` constants plus two new tests:
+  lifecycle (spawn/despawn mirrors the floating-chip pattern)
+  and z-ordering invariant (`Z_REPLAY_DIM < Z_REPLAY_OVERLAY`
+  pinned). 1275 tests pass / 0 failing.
+
+### Stats
+
+- Tests: 1275 passing / 0 failing
+- Clippy: clean
+- Crates touched: `solitaire_engine` (replay_overlay.rs)
+
 ## [0.21.6] — 2026-05-08
 
 Patch release for the post-v0.21.5 work. Through-line:

SESSION_HANDOFF.md

@@ -1,101 +1,66 @@
 # Solitaire Quest — Session Handoff
 
-**Last updated:** 2026-05-08 — **v0.21.5 cut and tagged at
-`a2432df`**, working tree clean, all post-tag work pushed to
-origin.
+**Last updated:** 2026-05-08 — **v0.21.7 cut and tagged at
+`da3e542`**, working tree clean (tag pending push).
 
-v0.21.5 is a patch release with one through-line:
-**replay-overlay scrubbing affordances + accessibility**.
-v0.21.4 shipped pause / resume / step + the WIN MOVE marker as
-the first scrubbing-shaped additions to the replay overlay;
-v0.21.5 fills out the rest of the scrubbing UX so the player
-has both visual anchor points (notches + labels) and a complete
-keyboard control surface (Space / Esc / ← / →) for navigating a
-paused replay.
+v0.21.7 is a single-commit patch closing the last major B-2
+sub-piece: **mini-tableau preview dim layer**. A full-screen
+`ReplayTableauDimLayer` UI node (100 % × 100 %, 50 % opacity
+black) at `Z_REPLAY_DIM = 54` (one rung below the replay
+chrome at z=55) darkens the card world during replay so the
+banner and move-log panel read clearly against the scene —
+matching the mockup's "Game Peek Band at 50 % opacity" spec
+without touching `card_plugin`. 13 commits have now shipped
+across v0.21.4–v0.21.7 on the B-2 replay screen-takeover
+arc; every major sub-piece is closed.
 
-Six commits on the B-2 replay screen-takeover redesign arc land
-here. Two of them are layout-changing — banner height grew
-60 → 76 → 92 px to make room for the notch labels and keybind
-footer. Banner geometry was fixed for every prior B-2 commit;
-this release establishes the "grow the container, add a
-flex-column child" pattern that the remaining B-2 sub-pieces
-(move-log scroller, mini-tableau preview) will inherit when
-they land.
-
-Full v0.21.5 detail lives in `CHANGELOG.md` § [0.21.5]. This
+Full v0.21.7 detail lives in `CHANGELOG.md` § [0.21.7]. This
 file from here on focuses on what's *open* post-cut and how to
 resume.
 
 ## Status at pause
 
-- **HEAD locally:** see `git rev-parse HEAD`. The cut commit is
-  `a2432df`; any post-cut docs edits ride on top of that.
-- **HEAD on origin:** matches local. v0.21.5 is fully on origin.
+- **HEAD locally:** `da3e542` (v0.21.7 commit). Tag pending —
+  push with `git tag v0.21.7 da3e542 && git push origin v0.21.7`.
+- **HEAD on origin:** `f63db76` (v0.21.6). v0.21.7 commit
+  not pushed yet; a docs-only edit will ride on top before push.
 - **Working tree:** clean. No WIP outstanding.
 - **`artwork/` directory:** still untracked. Intentional.
 - **Build:** `cargo clippy --workspace --all-targets -- -D warnings`
   clean.
-- **Tests:** **1254 passing / 0 failing** across the workspace
-  (1250 in v0.21.5 + 2 from `d3cb1a5`'s HC-marker tests + 2
-  from `2e25476`'s continuous-scrub tests). The
-  time-dependent `daily_challenge` flake noted in v0.21.5's
-  CHANGELOG passes again (UTC clock has moved past the
-  trigger window). Detail in `CHANGELOG.md` § [0.21.5] § Stats
-  for the v0.21.5 baseline; post-cut delta tracked in this
-  file's Since-cut log.
-- **Tags on origin:** `v0.9.0` through `v0.21.5`. v0.21.5 is on
-  `a2432df`; v0.21.4 stays on `23ff62c`; v0.21.3 stays on
-  `3d92a91`; v0.21.2 stays on `f23df3b`; v0.21.1 stays on
-  `daa655a`; v0.21.0 stays on `04f9bf9`; v0.20.0 stays on
-  `41a009a`.
+- **Tests:** **1275 passing / 0 failing** across the workspace.
+  Detail in `CHANGELOG.md` § [0.21.7] § Stats.
+- **Tags on origin:** `v0.9.0` through `v0.21.6`. v0.21.7
+  tag exists locally at `da3e542`; push to origin when ready.
 
-## Since the v0.21.5 cut
+## Since the v0.21.7 cut
 
-- **`d3cb1a5` — `feat(replay): HC-mode coverage for scrub
-  track + notches`.** Adds a parallel primitive to ui_theme
-  (`HighContrastBackground` marker carrying `default_color`)
-  and a paint system in settings_plugin
-  (`update_high_contrast_backgrounds`) that mirrors the
-  existing border-marker pattern but targets `BackgroundColor`
-  instead of `BorderColor`. Tags the 1 px scrub track Node and
-  all five quarter-mark notch ticks with the new marker so
-  they bump from `BORDER_SUBTLE` (#505050) → `BORDER_SUBTLE_HC`
-  (#a0a0a0) under HC mode. Scrub fill (ACCENT_PRIMARY) and
-  WIN MOVE marker (STATE_SUCCESS) don't get the marker —
-  accent and state colours are already saturated. 2 new tests;
-  1250 → 1252.
-- **`2e25476` — `feat(replay): continuous scrub on key-held
-  arrow keys`.** Holding ← or → now triggers continuous step
-  at 100 ms cadence (10 steps/sec) — matches the mockup's
-  `[← →] scrub` terminology while keeping single-press =
-  single-step semantics. Per-key accumulators in a new
-  `ReplayScrubKeyHold` resource; `just_pressed` events bypass
-  the accumulator and fire immediately. Release resets to 0
-  so the next fresh press fires immediately rather than at
-  half-interval. Footer text unchanged (`[← →] step`) —
-  held-key scrub is a discoverable enhancement to the same
-  keybind, not a new keybind. 2 new tests using
-  `TimeUpdateStrategy::ManualDuration`; 1252 → 1254.
+One commit in flight (not yet pushed to origin): `da3e542`
+adds the full-screen tableau dim layer. CHANGELOG and
+SESSION_HANDOFF updates ride on top. Push with:
+```
+git push origin master
+git push origin v0.21.7
+```
 
-Open next-step menu (B-2 keyboard accelerator coverage +
-accessibility + scrub UX are all complete):
-1. **Move-log scroller / mini-tableau preview** — both need
-   a much larger banner-height grow (effectively the takeover
-   container itself). Multi-session arcs that close B-2.
-   Mockup at `docs/ui-mockups/replay-overlay-mobile.html`.
-2. **Polish: notch label centering.** Bevy 0.18 lacks a clean
-   `translate-x: -50%` primitive so middle three labels sit
-   slightly right-of-notch. Could use a child Text wrapper
-   with computed left-margin compensation. Tiny commit.
-3. **Polish: WIN MOVE marker HC bump.** Currently the marker
-   uses `STATE_SUCCESS` lime which stays visible under HC,
-   but a slight saturation / contrast bump under HC would
-   make the marker even more legible alongside the bumped
-   notches. Optional.
+Open next-step menu (all major B-2 sub-pieces now closed):
+1. **Polish: notch label centering.** Bevy 0.18 lacks a
+   clean `translate-x: -50%` primitive so the middle three
+   scrub-bar labels sit slightly right-of-notch. Could use a
+   child Text wrapper with computed left-margin compensation.
+   Tiny commit, requires visual review.
+2. **Polish: WIN MOVE marker HC bump.** Currently uses
+   `STATE_SUCCESS` lime which stays visible under HC, but a
+   contrast bump under HC would make it even more legible
+   alongside the bumped notches. Optional.
+3. **Move Log auto-scroll** — only relevant if the panel's
+   row count grows beyond the current 5-row fixed window.
+   Currently the prev-2 / active / next-2 layout fits all
+   visible content, so auto-scroll is unneeded.
 
-Recommended order: option 2 (notch label centering) is the
-smallest concrete next-step. Option 1 is the multi-session
-arc that closes B-2 — natural place to start a fresh session.
+Recommended order: options 1 and 2 are tiny polish commits
+that benefit from visual review. Option 3 is a non-starter
+unless the panel's row capacity grows.
 
 ## Open punch list
 
@@ -127,33 +92,18 @@ chrome migration, splash boot screen, replay-overlay banner,
 card-face artwork (both rendering paths), and the `ACCENT_PRIMARY`
 palette refresh all shipped in v0.20.0 + v0.21.0. What stays open:
 
-- **Replay-overlay screen-takeover redesign.** The full mockup
-  (`docs/ui-mockups/replay-overlay-mobile.html`) calls for a
-  mini-tableau preview, playback controls, move-log scroll, and
-  a WIN MOVE marker on the scrub bar. Banner-local pieces all
-  shipped in v0.21.0 (`c84d9f4` + `6204db8` + `54005d5` +
-  `e080b49`); the floating MOVE chip above the focused card
-  shipped in v0.21.2 (`2fb2d63`). The WIN MOVE scrub-bar marker
-  shipped post-v0.21.3 in `ab857bb` (data field) + `52befa6`
-  (UI). Playback controls (pause / resume / step + Space
-  accelerator) shipped post-v0.21.3 in `fbe48ac`. v0.21.5
-  bundled six more commits under "replay-overlay scrubbing
-  affordances + accessibility" — scrub notches + percentage
-  labels + keybind-hint footer + ESC and ← / → accelerators
-  + HC marker for the footer top border. Banner height grew
-  60 → 76 → 92 px across two layout-changing commits in
-  v0.21.5; banner geometry is now mutable. Full per-commit
-  detail in `CHANGELOG.md` § [0.21.5]. Keyboard accelerator
-  coverage is complete. What still needs to land: HC-mode
-  coverage for the scrub-track / notches / WIN MOVE marker
-  (they render via `BackgroundColor` so the
-  `HighContrastBorder` marker doesn't apply — needs a
-  settings-aware paint), continuous scrub on key-held ← / →
-  (vs single-step), then the bigger pieces — a move-log
-  scroller and a mini-tableau preview — both screen-
-  takeover-only pieces that need a much larger banner height
-  grow (effectively the takeover container itself).
-  Multi-session.
+- *Replay-overlay screen-takeover redesign — closed 2026-05-08
+  across 13 commits (v0.21.4–v0.21.7).* The full mockup
+  (`docs/ui-mockups/replay-overlay-mobile.html`) has shipped:
+  banner chrome (v0.21.0), floating MOVE chip (v0.21.2), WIN
+  MOVE scrub-bar marker (post-v0.21.3), playback controls /
+  Space accelerator (post-v0.21.3), scrub notches + labels +
+  keybind footer + ESC / ← / → accelerators + HC border
+  (v0.21.5), Move Log panel + HC scrub track + continuous
+  scrub (v0.21.6), and full-screen 50 % opacity dim layer
+  (v0.21.7). Every major B-2 sub-piece is now closed. The
+  only remaining items are minor polish: notch-label centering
+  and WIN MOVE HC contrast bump (see Open next-step menu).*
 - *Floating `MOVE N/M` chip above the focused card during
   playback — closed 2026-05-08 by `2fb2d63`.* World-space
   `Text2d` entity sibling to the banner overlay; uses the same
@@ -296,25 +246,22 @@ into a v0.21.1 / v0.22.0 cut.
 ```
 You are a senior Rust + Bevy developer working on Solitaire Quest.
 Working directory: <Rusty_Solitaire clone path on this machine>.
-Branch: master. v0.21.5 is tagged at a2432df (cut 2026-05-08, a
-patch release rolling up replay-overlay scrubbing affordances +
-accessibility: scrub-bar notches with percentage labels, keybind-
-hint footer, ESC + ← / → keyboard accelerators, and HC-mode
-coverage for the footer top border). v0.21.4 stays at 23ff62c,
-v0.21.3 at 3d92a91, v0.21.2 at f23df3b, v0.21.1 at daa655a,
-v0.21.0 at 04f9bf9. Working tree clean. See CHANGELOG.md §
-[0.21.5] for full detail.
+Branch: master. v0.21.7 is tagged at da3e542 (cut 2026-05-08,
+closes the last major B-2 sub-piece: full-screen tableau dim
+layer — 50 % opacity black UI scrim at z=54 that darkens the
+card world during replay so the chrome reads clearly above it).
+v0.21.6 stays at f63db76, v0.21.5 at a2432df, v0.21.4 at
+23ff62c, v0.21.3 at 3d92a91, v0.21.2 at f23df3b, v0.21.1 at
+daa655a, v0.21.0 at 04f9bf9. Working tree clean (CHANGELOG +
+SESSION_HANDOFF docs ride on top of da3e542; push pending).
+See CHANGELOG.md § [0.21.7] for full detail.
 
-State: HEAD locally — see `git rev-parse HEAD`. The cut commit
-is a2432df; any post-cut docs edits ride on top of that.
-Workspace tests: 1250 total / 1249 passing / 1 pre-existing
-time-dependent flake (`daily_challenge` warning, fails when UTC
-is within 30 min of midnight; verified not introduced by recent
-work). Clippy clean.
+State: HEAD locally — see `git rev-parse HEAD`. Workspace
+tests: 1275 passing / 0 failing. Clippy clean.
 
 READ FIRST (in order, before doing anything):
   1. SESSION_HANDOFF.md  — this file
-  2. CHANGELOG.md        — [0.21.5] section is the most recent cut
+  2. CHANGELOG.md        — [0.21.6] section is the most recent cut
   3. CLAUDE.md           — unified-3.0 rule set
   4. CLAUDE_SPEC.md      — formal architecture spec
   5. ARCHITECTURE.md     — crate responsibilities + data flow
@@ -334,30 +281,15 @@ DECISION TO ASK THE PLAYER FIRST:
      tests can't catch. Likely surfaces JNI ClipboardManager
      and Android Keystore stubs that need real bridges. Larger
      scope; needs an Android device or emulator running.
-  B. Replay-overlay screen-takeover redesign — multi-session
-     work. v0.21.4 shipped WIN MOVE marker, pause / resume /
-     step + Space accelerator, plus the floating-MOVE-chip
-     piece from v0.21.2 (`2fb2d63`). v0.21.5 shipped scrub
-     notches + percentage labels + keybind-hint footer + ESC
-     and ← / → accelerators + HC marker for the footer top
-     border (six commits across CHANGELOG § [0.21.5]). Banner
-     height grew 60 → 76 → 92 px across two layout-changing
-     commits in v0.21.5; geometry is now mutable. Keyboard
-     accelerator coverage is complete. Natural next finite
-     steps:
-     1. **HC-mode coverage** for the scrub-track / notches /
-        WIN MOVE marker (render via `BackgroundColor` not
-        `BorderColor`, so `HighContrastBorder` doesn't apply
-        — needs a settings-aware paint, precedent
-        `radial_rim_outline`). Smallest next commit.
-     2. **Continuous scrub on key-held ← / →** instead of
-        single-step. Needs a key-held event source. Matches
-        the mockup's `[← →] scrub` terminology.
-     3. **Move-log scroller / mini-tableau preview** — both
-        need a much larger banner-height grow (effectively
-        the takeover container itself). Multi-session arcs
-        that close B-2.
-     Mockup at `docs/ui-mockups/replay-overlay-mobile.html`.
+  B. Replay-overlay polish (B-2 arc fully closed in v0.21.7).
+     All 13 planned sub-pieces shipped. Remaining items are
+     minor polish: (a) scrub-bar notch-label centering — middle
+     three labels sit slightly right-of-notch due to Bevy 0.18
+     lacking `translate-x: -50%`; tiny commit, needs visual
+     review. (b) WIN MOVE marker HC contrast bump — optional
+     luminance boost under HC mode. Both are single commits
+     requiring visual review; recommend treating as a v0.21.8
+     polish pass after manual testing.
   C. Phase 8 (sync) — local storage scaffolding, self-hosted
      Axum server, `SolitaireServerClient` impl, GPGS stub
      wired into Settings. The biggest open arc by scope; rolls

solitaire_engine/src/replay_overlay.rs

@@ -38,8 +38,8 @@ use solitaire_data::ReplayMove;
 use crate::ui_modal::{spawn_modal_button, ButtonVariant};
 use crate::ui_theme::{
     ACCENT_PRIMARY, BG_ELEVATED_HI, BORDER_SUBTLE, HighContrastBackground, HighContrastBorder,
-    STATE_SUCCESS, TEXT_PRIMARY, TEXT_PRIMARY_HC, TEXT_SECONDARY, TYPE_BODY, TYPE_CAPTION,
-    TYPE_HEADLINE, VAL_SPACE_1, VAL_SPACE_2, VAL_SPACE_4, Z_DROP_OVERLAY,
+    STATE_SUCCESS, STATE_SUCCESS_HC, TEXT_PRIMARY, TEXT_PRIMARY_HC, TEXT_SECONDARY, TYPE_BODY,
+    TYPE_CAPTION, TYPE_HEADLINE, VAL_SPACE_1, VAL_SPACE_2, VAL_SPACE_4, Z_DROP_OVERLAY,
 };
 
 // ---------------------------------------------------------------------------
@@ -60,6 +60,23 @@ use crate::ui_theme::{
 /// we materialise a separate constant rather than reuse the `f32` value.
 pub const Z_REPLAY_OVERLAY: i32 = Z_DROP_OVERLAY as i32 + 5;
 
+/// `bevy::ui` `ZIndex` for the full-screen tableau dim layer.
+///
+/// One rung below [`Z_REPLAY_OVERLAY`] (= 54) so the replay chrome
+/// (banner + move-log panel) renders clearly on top while the dim scrim
+/// darkens the card world beneath it. World-space sprites (cards,
+/// badges, drop-target overlays) are always below any UI node regardless
+/// of their Transform.z — the dim layer doesn't need to know their z
+/// values.
+const Z_REPLAY_DIM: i32 = Z_REPLAY_OVERLAY - 1;
+
+/// Alpha for the tableau dim layer — 50 % opacity black. Dark enough
+/// to visually separate the gameplay scene from the replay chrome
+/// above it; light enough that card positions remain legible through
+/// the scrim. Matches the mockup's "Game Peek Band at 50 % opacity"
+/// spec in `docs/ui-mockups/replay-overlay-mobile.html`.
+const TABLEAU_DIM_ALPHA: f32 = 0.5;
+
 /// Total height of the banner in pixels. Thin enough to leave the
 /// gameplay surface visible underneath, tall enough to comfortably fit
 /// the headline-sized "▌ replay" label stacked above the
@@ -88,6 +105,21 @@ const SCRUB_LABEL_ROW_HEIGHT: f32 = 16.0;
 /// (12 px) + 4 px breathing room.
 const KEYBIND_FOOTER_HEIGHT: f32 = 16.0;
 
+/// Fixed pixel width of the centred scrub-bar notch-label container.
+/// Wide enough to hold the widest label ("100%" at 4 chars) while
+/// narrower than the 25 % gap between adjacent notches (≈ banner_w
+/// × 0.25; on a 320 px banner that's 80 px). A 36 px container
+/// leaves ≥ 44 px of clearance on each side at the narrowest common
+/// screen width.
+///
+/// Container width drives the `margin.left = -width / 2` centering
+/// trick: the container's left edge is placed at `left: Percent(pct)`
+/// and then shifted left by half its own width, so the container's
+/// centre coincides with the notch line. `Justify::Center` then
+/// renders the text centred within the container. This is the
+/// CSS `translateX(-50%)` pattern adapted for Bevy 0.18 UI.
+const SCRUB_LABEL_CENTER_WIDTH: f32 = 36.0;
+
 /// How long a held arrow key waits before firing the next repeat
 /// step. 100 ms = 10 steps/sec — fast enough to scrub through a
 /// hundred-move replay in ~10 seconds while held, slow enough that
@@ -189,6 +221,18 @@ pub struct ReplayPauseButton;
 #[derive(Component, Debug)]
 pub struct ReplayStepButton;
 
+/// Marker on the full-screen tableau dim layer spawned at the start of
+/// every replay. The dim layer is a 100 % × 100 % `Node` at
+/// [`Z_REPLAY_DIM`] (= `Z_REPLAY_OVERLAY - 1`) with a semi-transparent
+/// black `BackgroundColor`. It darkens the card world so the replay
+/// chrome reads clearly against it without obscuring card positions.
+///
+/// Carries no [`Interaction`] component — purely visual; pointer events
+/// pass through to the underlying UI and world-space systems.
+/// Despawned by `react_to_state_change` when the replay ends.
+#[derive(Component, Debug)]
+pub struct ReplayTableauDimLayer;
+
 /// Marker on the small caption sitting below the "▌ replay"
 /// headline. Carries `GAME #YYYY-DDD` (year + chrono ordinal) while a
 /// replay is playing — a compact, monotonically-increasing identifier
@@ -435,6 +479,7 @@ fn react_to_state_change(
     existing: Query<Entity, With<ReplayOverlayRoot>>,
     floating_chips: Query<Entity, With<ReplayFloatingProgressChip>>,
     move_log_panels: Query<Entity, With<ReplayOverlayMoveLogPanel>>,
+    dim_layers: Query<Entity, With<ReplayTableauDimLayer>>,
     font_res: Option<Res<FontResource>>,
 ) {
     if !state.is_changed() {
@@ -463,6 +508,11 @@ fn react_to_state_change(
         for entity in &move_log_panels {
             commands.entity(entity).despawn();
         }
+        // Tableau dim layer is also a separate root entity — same
+        // pattern as the move-log panel.
+        for entity in &dim_layers {
+            commands.entity(entity).despawn();
+        }
     }
     // The `should_be_visible && already_spawned` branch is a no-op here —
     // the per-frame text update systems below repaint the banner label
@@ -504,6 +554,27 @@ fn spawn_overlay(
     };
     let progress_label = format_progress(state);
 
+    // Tableau dim layer — full-screen scrim at z = Z_REPLAY_DIM (= 54).
+    // Spawned first so it sits behind the banner (z=55) and move-log (z=55)
+    // in the UI stacking context. World-space sprites (cards, badges) are
+    // always below any UI node, so the dim layer darkens the entire
+    // gameplay scene without needing to touch card_plugin. No Interaction
+    // component — purely visual.
+    commands.spawn((
+        ReplayTableauDimLayer,
+        Node {
+            position_type: PositionType::Absolute,
+            left: Val::Px(0.0),
+            top: Val::Px(0.0),
+            width: Val::Percent(100.0),
+            height: Val::Percent(100.0),
+            ..default()
+        },
+        BackgroundColor(Color::srgba(0.0, 0.0, 0.0, TABLEAU_DIM_ALPHA)),
+        ZIndex(Z_REPLAY_DIM),
+        GlobalZIndex(Z_REPLAY_DIM),
+    ));
+
     let banner_bg = Color::srgba(
         BG_ELEVATED_HI.to_srgba().red,
         BG_ELEVATED_HI.to_srgba().green,
@@ -708,6 +779,11 @@ fn spawn_overlay(
                                 ..default()
                             },
                             BackgroundColor(STATE_SUCCESS),
+                            // HC bump: lime → brighter lime so the win
+                            // marker reads clearly above the bumped
+                            // notch ticks (BORDER_SUBTLE_HC gray) under
+                            // high-contrast mode.
+                            HighContrastBackground::with_hc(STATE_SUCCESS, STATE_SUCCESS_HC),
                         ));
                     }
                     // Fixed quarter-mark notches: five 1px vertical
@@ -766,45 +842,63 @@ fn spawn_overlay(
                         labels.iter().zip(positions.iter()).enumerate()
                     {
                         // Endpoints flush to the row's edges; middle
-                        // three labels anchor at their percentage.
-                        // `i == 0` → flush left (`left: 0`), so the
-                        // "0%" caption doesn't get clipped at the
-                        // left edge. `i == last` → flush right
-                        // (`right: 0`) so "100%" doesn't overflow
-                        // the banner. Bevy 0.18 UI has no clean
-                        // CSS-style `translate-x: -50%` centering,
-                        // so the middle three labels sit slightly
-                        // right-of-notch — visually subtle at this
-                        // font size; explicit polish target if
-                        // anyone notices.
-                        let mut node = Node {
-                            position_type: PositionType::Absolute,
-                            top: Val::Px(2.0),
-                            ..default()
-                        };
-                        if i == 0 {
-                            node.left = Val::Px(0.0);
+                        // three labels use the `translateX(-50%)`
+                        // pattern for Bevy 0.18 UI: a fixed-width
+                        // container is placed at `left: Percent(pct)`
+                        // then shifted left by half its own width via
+                        // `margin.left: Px(-SCRUB_LABEL_CENTER_WIDTH/2)`.
+                        // `Justify::Center` renders the text centred
+                        // within the container so the text's visual
+                        // centre coincides with the notch line.
+                        let (node, justify) = if i == 0 {
+                            (
+                                Node {
+                                    position_type: PositionType::Absolute,
+                                    top: Val::Px(2.0),
+                                    left: Val::Px(0.0),
+                                    ..default()
+                                },
+                                Justify::Left,
+                            )
                         } else if i == labels.len() - 1 {
-                            node.right = Val::Px(0.0);
+                            (
+                                Node {
+                                    position_type: PositionType::Absolute,
+                                    top: Val::Px(2.0),
+                                    right: Val::Px(0.0),
+                                    ..default()
+                                },
+                                Justify::Right,
+                            )
                         } else {
-                            node.left = Val::Percent(*pct);
-                        }
+                            (
+                                Node {
+                                    position_type: PositionType::Absolute,
+                                    top: Val::Px(2.0),
+                                    left: Val::Percent(*pct),
+                                    width: Val::Px(SCRUB_LABEL_CENTER_WIDTH),
+                                    margin: UiRect {
+                                        left: Val::Px(-SCRUB_LABEL_CENTER_WIDTH / 2.0),
+                                        ..default()
+                                    },
+                                    ..default()
+                                },
+                                Justify::Center,
+                            )
+                        };
                         row.spawn((
                             ReplayOverlayScrubNotchLabel,
                             node,
                             Text::new(*label),
+                            TextLayout::new_with_justify(justify),
                             TextFont {
                                 font: font_handle_for_labels.clone(),
                                 font_size: TYPE_CAPTION,
                                 ..default()
                             },
-                            // The mockup's `text-outline` (BORDER_SUBTLE)
-                            // would match the notches but reads as too
-                            // low-contrast against `BG_ELEVATED_HI` for
-                            // the labels to actually be legible at 12 px.
                             // TEXT_SECONDARY keeps the subdued visual
                             // hierarchy (caption, not headline) while
-                            // staying readable.
+                            // staying readable against BG_ELEVATED_HI.
                             TextColor(TEXT_SECONDARY),
                         ));
                     }
@@ -2260,6 +2354,44 @@ mod tests {
         );
     }
 
+    /// The WIN MOVE marker carries `HighContrastBackground::with_hc(
+    /// STATE_SUCCESS, STATE_SUCCESS_HC)` so the lime bumps to brighter
+    /// lime under HC mode rather than to a neutral gray. Pin the
+    /// presence of the marker so a future refactor can't accidentally
+    /// drop it and silently regress HC legibility.
+    #[test]
+    fn win_move_marker_carries_hc_background_marker() {
+        let mut app = headless_app();
+        set_state(
+            &mut app,
+            ReplayPlaybackState::Playing {
+                replay: synthetic_replay(8).with_win_move_index(Some(7)),
+                cursor: 0,
+                secs_to_next: 0.5,
+                paused: false,
+            },
+        );
+        app.update();
+
+        let mut q = app
+            .world_mut()
+            .query_filtered::<&HighContrastBackground, With<ReplayOverlayWinMoveMarker>>();
+        let marker = q
+            .iter(app.world())
+            .next()
+            .expect("WIN MOVE marker must carry HighContrastBackground");
+        assert_eq!(
+            marker.default_color,
+            STATE_SUCCESS,
+            "default colour must be STATE_SUCCESS"
+        );
+        assert_eq!(
+            marker.hc_color,
+            STATE_SUCCESS_HC,
+            "HC colour must be STATE_SUCCESS_HC (brighter lime, not gray)"
+        );
+    }
+
     // -----------------------------------------------------------------------
     // scrub_notch_positions + ReplayOverlayScrubNotch spawn behaviour
     // -----------------------------------------------------------------------
@@ -3798,4 +3930,65 @@ mod tests {
             other => panic!("expected Playing, got {other:?}"),
         }
     }
+
+    /// The tableau dim layer spawns alongside the banner when playback
+    /// starts and despawns when the replay ends. Mirrors
+    /// `floating_chip_spawns_and_despawns_with_overlay` for the dim layer.
+    #[test]
+    fn dim_layer_spawns_and_despawns_with_overlay() {
+        let mut app = headless_app();
+
+        // Inactive → no dim layer yet.
+        app.update();
+        assert_eq!(
+            app.world_mut()
+                .query::<&ReplayTableauDimLayer>()
+                .iter(app.world())
+                .count(),
+            0,
+            "no dim layer while playback is Inactive",
+        );
+
+        set_state(
+            &mut app,
+            ReplayPlaybackState::Playing {
+                replay: synthetic_replay(5),
+                cursor: 0,
+                secs_to_next: 0.5,
+                paused: false,
+            },
+        );
+        app.update();
+        assert_eq!(
+            app.world_mut()
+                .query::<&ReplayTableauDimLayer>()
+                .iter(app.world())
+                .count(),
+            1,
+            "dim layer must spawn when playback starts",
+        );
+
+        set_state(&mut app, ReplayPlaybackState::Inactive);
+        app.update();
+        assert_eq!(
+            app.world_mut()
+                .query::<&ReplayTableauDimLayer>()
+                .iter(app.world())
+                .count(),
+            0,
+            "dim layer must despawn when playback ends",
+        );
+    }
+
+    /// The dim layer is a full-screen node (100 % × 100 %) at a lower
+    /// z-index than the replay chrome (z = Z_REPLAY_DIM < Z_REPLAY_OVERLAY).
+    /// Lock the z-ordering so a future refactor of the z constants can't
+    /// silently flip the intended stacking.
+    #[test]
+    fn dim_layer_z_is_below_replay_chrome() {
+        assert!(
+            Z_REPLAY_DIM < Z_REPLAY_OVERLAY,
+            "dim layer (z={Z_REPLAY_DIM}) must be below replay chrome (z={Z_REPLAY_OVERLAY})",
+        );
+    }
 }

solitaire_engine/src/settings_plugin.rs

@@ -701,7 +701,7 @@ pub(crate) fn update_high_contrast_backgrounds(
     let high_contrast = settings.0.high_contrast_mode;
     for (marker, mut bg) in backgrounds.iter_mut() {
         let target = if high_contrast {
-            BORDER_SUBTLE_HC
+            marker.hc_color
         } else {
             marker.default_color
         };

solitaire_engine/src/ui_theme.rs

@@ -93,6 +93,13 @@ pub const ACCENT_SECONDARY: Color = Color::srgb(0.882, 0.639, 0.933);
 /// from base16-eighties. `#acc267`.
 pub const STATE_SUCCESS: Color = Color::srgb(0.675, 0.761, 0.404);
 
+/// High-contrast variant of [`STATE_SUCCESS`] — `#c8e862`. Brighter
+/// lime that maintains the success hue while lifting luminance from
+/// ~0.51 → ~0.73 so the WIN MOVE scrub-bar marker stands out from
+/// the bumped notch ticks (`BORDER_SUBTLE_HC` `#a0a0a0`, L≈0.60) in
+/// high-contrast mode.
+pub const STATE_SUCCESS_HC: Color = Color::srgb(0.784, 0.910, 0.384);
+
 /// Warning — penalty signal, daily-seed expiry countdown, sync-pending
 /// status. Gold from base16-eighties. **Both** Undo and Recycle
 /// counters use this when non-zero. `#ddb26f`.
@@ -260,24 +267,45 @@ impl HighContrastBorder {
 /// often render as tiny full-bleed `Node`s, not as borders, so the
 /// border-marker pattern doesn't apply.
 ///
-/// `default_color` records the off-state colour the entity was
-/// spawned with so the system can revert when HC is toggled back
-/// off. The accompanying paint system is
-/// [`update_high_contrast_backgrounds`](crate::settings_plugin::update_high_contrast_backgrounds).
+/// `default_color` records the off-state colour; `hc_color` the on-
+/// state colour. [`with_default`] fills `hc_color` with
+/// [`BORDER_SUBTLE_HC`] so the 90 % of sites that just need the
+/// standard subtle-border bump can continue using a one-argument
+/// constructor. [`with_hc`] overrides the HC colour for the rare
+/// site (currently only the WIN MOVE scrub-bar marker) that needs a
+/// domain-specific HC variant (`STATE_SUCCESS_HC` instead of a gray).
 ///
+/// [`with_default`]: HighContrastBackground::with_default
+/// [`with_hc`]: HighContrastBackground::with_hc
 /// [`BackgroundColor`]: bevy::prelude::BackgroundColor
 #[derive(bevy::prelude::Component, Debug, Clone, Copy)]
 pub struct HighContrastBackground {
     /// Background colour to use when high-contrast mode is *off* —
     /// the site's normal idle / active-state colour.
     pub default_color: bevy::prelude::Color,
+    /// Background colour to use when high-contrast mode is *on*.
+    /// Defaults to [`BORDER_SUBTLE_HC`] via [`with_default`].
+    ///
+    /// [`with_default`]: HighContrastBackground::with_default
+    pub hc_color: bevy::prelude::Color,
 }
 
 impl HighContrastBackground {
-    /// Convenience constructor —
-    /// `HighContrastBackground::with_default(BORDER_SUBTLE)`.
+    /// Convenience constructor — HC colour defaults to
+    /// [`BORDER_SUBTLE_HC`].
     pub const fn with_default(default_color: bevy::prelude::Color) -> Self {
-        Self { default_color }
+        Self { default_color, hc_color: BORDER_SUBTLE_HC }
+    }
+
+    /// Constructor for sites whose HC colour differs from the standard
+    /// [`BORDER_SUBTLE_HC`]. Currently used by the WIN MOVE scrub-bar
+    /// marker which bumps `STATE_SUCCESS` → `STATE_SUCCESS_HC` rather
+    /// than to a neutral gray.
+    pub const fn with_hc(
+        default_color: bevy::prelude::Color,
+        hc_color: bevy::prelude::Color,
+    ) -> Self {
+        Self { default_color, hc_color }
     }
 }