fix(theme): kill flash of white on dark-themed load

The app painted white until <ThemeProvider> mounted and set data-theme, then snapped to the dark theme. Two fixes: - Inline head script (rsbuild html.tags) sets data-theme before first paint, mirroring modern-sk's exact logic (localStorage 'modern-sk-theme' || 'dark') so there's no second flip when the provider mounts. Inline = zero round-trips. - body now paints var(--color-bg) so the themed background shows before React mounts #root and layers the felt grain on top. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-09 13:18:29 +03:00
2 changed files with 17 additions and 0 deletions
@@ -36,6 +36,18 @@ export default defineConfig({
    // "Install app". The service worker (audio offline cache) is registered
    // from src/index.tsx, not here.
    tags: [
      // Theme bootstrap — runs inline before first paint to kill the flash of
      // white on a dark-themed load. Mirrors modern-sk's own logic exactly
      // (localStorage 'modern-sk-theme' || 'dark' → data-theme on <html>), so
      // there's no second flip when <ThemeProvider> mounts. Inline (not an
      // external file) so it costs zero round-trips.
      {
        tag: 'script',
        children:
          "(function(){try{var t=localStorage.getItem('modern-sk-theme')||'dark';document.documentElement.setAttribute('data-theme',t);}catch(e){}})();",
        head: true,
        append: false,
      },
      // Runtime operator config. A classic (non-deferred) head script, so it
      // runs before the deferred app bundle and window.__APP_CONFIG__ is set by
      // the time src/config/env.ts reads it. Served from public/ in dev and
@@ -28,6 +28,11 @@ body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--fg-1);
  /* Paint the themed background immediately. The inline theme script in
     index.html (see rsbuild.config.ts) sets [data-theme] before first paint, so
     --color-bg resolves to the right value here before React mounts #root and
     layers the .modern-sk-felt grain on top — no flash of white. */
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
 }