0.2.3: the install icon keeps the 0.2.x mint rook (the owner's choice), refined: a narrower tower, lighter base and more padding so it sits well among launcher icons; manifest sizes, maskable and favicons re-exported (the ICO keeps its transparent mask)

docs/history/0.2.3.md

@@ -275,19 +275,27 @@ Based on @Cromemadnd's proposal, with a one-use install controller. Buttons appe
 standalone/fullscreen and installed sessions hide them. Accept, dismiss, failure and duplicate clicks all consume the
 same offer once. See [the prompt API](https://developer.mozilla.org/en-US/docs/Web/API/BeforeInstallPromptEvent/prompt)
 and [installability requirements](https://developer.mozilla.org/en-US/docs/Web/Progressive_web_apps/Guides/Making_PWAs_installable).
-The 2026-10-10 icon revision replaces the previous mint rook with an original, season-independent fortress / shield
-and defended square. Its neutral grey palette and geometry use no official logos, artwork, icons or fonts and no
-Alliance lettering or seasonal insignia. `public/icons/app.svg` is the master; `tools/export-app-icons.py` exports
+The maintainer revised the icon direction on 2026-10-10: **沿用 0.2.x 的薄荷绿城堡并精修**.
+The selected B refinement keeps the previous mint rook's three battlements, inset tower and splayed base,
+with a narrower tower, balanced battlements, thinner base and more breathing room. It retains mint `#4ed8af`
+on dark `#0c0f0e`, without text, gradients, gloss or official logos, artwork, icons or fonts.
+The source is the project's `public/icons/app.svg` from before `ba5b998a`; the local `icon-v2` review includes
+the original and A/B/C proposals at large and small sizes, on light/dark backgrounds and simulated home screens.
+`public/icons/app.svg` is the selected B master; `tools/export-app-icons.py` exports
 192/512 px `any` and separate opaque `maskable` PNGs (the mark stays inside the central 40%-radius safe circle),
 16/32/48 px PNG / ICO favicons and a 180 px Apple touch icon. All ship outside optional game art, including lite
 packages. See ASSETS.md for the source, reproduction command and originality statement.
+The offline revision also corrects the ICO writer's transparency masks: each 16/32/48 px frame now uses its own
+native-size render and 4-byte-aligned opaque mask rows. Decoding previously exposed transparent holes in the 48 px
+frame; the regression checks mask layout / opacity and compares every ICO colour pixel with its PNG counterpart.
 No service worker or offline cache is installed; the server is still required.
 The lobby keeps Settings immediately before How to Play even when the optional install/recovery buttons appear;
 the full browser run caught and corrected an initial insertion between that established pair.
 The settings-entry check tests the absent board-style/background-music option labels, allowing the text-size help
 to explain that the board keeps its scale.
 
-Tests: offer lifecycle/disposal, decoded PNG dimensions / opacity / maskable safe zone, favicon references and packaging inclusion.
+Tests: offer lifecycle/disposal, decoded PNG dimensions / opacity / mint palette / maskable safe zone,
+three distinct battlements and an inset tower at 16/32/48 px, favicon references and packaging inclusion.
 The initial feature also had real Chrome manifest and installability checks, and a synthetic
 dismissed offer through the actual button. Initial incognito rejection was a test-environment limitation; the real
 installability check runs in Chrome's ordinary temporary profile. Native OS installation itself is not performed.