fix(fonts): the app uses Inter again (#320)

Since the switch to @fontsource-variable/inter 5 (May), the package
registers the family 'Inter Variable', but the app still asked for the
4.x name 'InterVariable', so every user got their platform's default
sans-serif (Arial / Helvetica / DejaVu) and Settings → Appearance →
font "Inter" did nothing.

--font-secondary (index.css) and the App font map now ask for
'Inter Variable' first, keeping 'InterVariable' as a fallback for a
locally installed old version.

Verified headless: before, 0 Inter faces loaded and
document.fonts.check('16px "Inter Variable"') false; now the face loads
and the check is true.

Fixes #320

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/features/lotus/backgrounds/animAurora.ts

@@ -51,7 +51,7 @@ const dark: CSSProperties = {
   backgroundSize: '260% 240%, 300% 260%, 240% 280%, 220% 200%, 100% 100%, 100% 100%',
   backgroundPosition: '0% 30%, 100% 70%, 50% 0%, 20% 80%, 50% 50%, 50% 50%',
   backgroundRepeat: 'no-repeat',
-  animation: `${auroraFlow} 60s ease-in-out infinite`,
+  animation: `${auroraFlow} 60s steps(180) infinite`,
 };
 
 const light: CSSProperties = {
@@ -75,7 +75,7 @@ const light: CSSProperties = {
   backgroundSize: '260% 240%, 300% 260%, 240% 280%, 220% 200%, 100% 100%, 100% 100%',
   backgroundPosition: '0% 30%, 100% 70%, 50% 0%, 20% 80%, 50% 50%, 50% 50%',
   backgroundRepeat: 'no-repeat',
-  animation: `${auroraFlow} 60s ease-in-out infinite`,
+  animation: `${auroraFlow} 60s steps(180) infinite`,
 };
 
 export const animAurora: ChatBgVariants = { dark, light };

src/app/features/lotus/backgrounds/animFireflies.ts

@@ -55,7 +55,7 @@ export const animFireflies: ChatBgVariants = {
       '0 0', // wash A   (static)
       '0 0', // wash B   (static)
     ].join(','),
-    animation: `${firefliesDrift} 44s linear infinite`,
+    animation: `${firefliesDrift} 44s steps(528) infinite`,
   },
 
   // Light: a cozy warm dim-dusk. No harsh dots on white — soft amber motes with
@@ -93,6 +93,6 @@ export const animFireflies: ChatBgVariants = {
       '0 0', // wash A   (static)
       '0 0', // wash B   (static)
     ].join(','),
-    animation: `${firefliesDrift} 44s linear infinite`,
+    animation: `${firefliesDrift} 44s steps(528) infinite`,
   },
 };

src/app/features/lotus/backgrounds/animPulse.ts

@@ -76,7 +76,7 @@ export const animPulse: ChatBgVariants = {
       '0 0', // base wash
       '0 0', // vignette
     ].join(','),
-    animation: `${gridPulse} 22s ease-in-out infinite`,
+    animation: `${gridPulse} 22s steps(528) infinite`,
   },
 
   // Light: soft slate-blue grid on pale cool-white, a gentle luminance breathe.
@@ -116,6 +116,6 @@ export const animPulse: ChatBgVariants = {
       '0 0', // base wash
       '0 0', // vignette
     ].join(','),
-    animation: `${gridPulse} 22s ease-in-out infinite`,
+    animation: `${gridPulse} 22s steps(528) infinite`,
   },
 };

src/app/features/lotus/backgrounds/animRain.ts

@@ -97,7 +97,7 @@ export const animRain: ChatBgVariants = {
     ].join(','),
     backgroundSize: ['260px 200px', '100% 100%', '100% 100%', '100% 100%'].join(','),
     backgroundPosition: ['0 0', '0 0', '0 0', '0 0'].join(','),
-    animation: `${rainFall} 12s linear infinite`,
+    animation: `${rainFall} 12s steps(288) infinite`,
   },
 
   // Light: soft teal-grey streaks on a pale cool base — elegant, never neon.
@@ -118,6 +118,6 @@ export const animRain: ChatBgVariants = {
     ].join(','),
     backgroundSize: ['260px 200px', '100% 100%', '100% 100%', '100% 100%'].join(','),
     backgroundPosition: ['0 0', '0 0', '0 0', '0 0'].join(','),
-    animation: `${rainFall} 12s linear infinite`,
+    animation: `${rainFall} 12s steps(288) infinite`,
   },
 };

src/app/features/lotus/backgrounds/animStars.ts

@@ -68,7 +68,7 @@ export const animStars: ChatBgVariants = {
       '0 0', // nebula A
       '0 0', // nebula B
     ].join(','),
-    animation: `${starDrift} 90s linear infinite`,
+    animation: `${starDrift} 90s steps(1080) infinite`,
   },
 
   // Light: an airy pre-dawn sky. No literal white-on-white stars — instead very
@@ -112,6 +112,6 @@ export const animStars: ChatBgVariants = {
       '0 0', // wash A
       '0 0', // wash B
     ].join(','),
-    animation: `${starDrift} 100s linear infinite`,
+    animation: `${starDrift} 100s steps(1200) infinite`,
   },
 };

src/app/features/lotus/chatBackground.ts

@@ -149,6 +149,11 @@ export const getChatBg = (
   }
   // For animated backgrounds, promote the element to its own compositor layer so
   // background-position keyframes don't trigger repaints on descendant elements.
+  // [Gitea #337] background-position can't run on the compositor, so every
+  // animation frame repaints the whole chat area (45 to 70% main-thread busy
+  // at 60 fps). The drifts are slow (3–22 px/s), so each animation uses steps():
+  // ~12 updates/s for the slow ones, ~24/s for rain and pulse: visually the
+  // same, a fraction of the repaints.
   if (style.animation) {
     return { ...style, willChange: 'background-position', contain: 'paint' };
   }

src/app/pages/App.tsx

@@ -48,7 +48,7 @@ import {
 const EMOJI_FONTS = 'var(--font-flags), var(--font-emoji)';
 const FONT_MAP: Record<string, string> = {
   system: `system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', ${EMOJI_FONTS}, sans-serif`,
-  inter: `'InterVariable', ${EMOJI_FONTS}, sans-serif`,
+  inter: `'Inter Variable', 'InterVariable', ${EMOJI_FONTS}, sans-serif`,
   'jetbrains-mono': `'JetBrains Mono', ${EMOJI_FONTS}, monospace`,
   'fira-code': `'Fira Code', ${EMOJI_FONTS}, monospace`,
 };

src/index.css

@@ -42,7 +42,8 @@
 
   --font-emoji: 'Twemoji_DISABLED';
   --font-flags: 'TwemojiFlags_DISABLED';
-  --font-secondary: 'InterVariable', var(--font-flags), var(--font-emoji), sans-serif;
+  --font-secondary:
+    'Inter Variable', 'InterVariable', var(--font-flags), var(--font-emoji), sans-serif;
 }
 
 .dark-theme,
@@ -66,7 +67,7 @@
   --mx-uc-7: hsl(243, 100%, 80%);
   --mx-uc-8: hsl(94, 100%, 80%);
 
-  --font-secondary: 'InterVariable', var(--font-emoji), sans-serif;
+  --font-secondary: 'Inter Variable', 'InterVariable', var(--font-emoji), sans-serif;
 }
 
 html {