feat(frontend): Modern palette CSS variables + Inter Tight/JetBrains Mono fonts

src/index.css

@@ -1,3 +1,8 @@
+/* Inter Tight (UI sans) + JetBrains Mono (data/mono) for the claim-drawer
+   Modern palette. Loaded via Google Fonts CDN. Project default face (Geist
+   Mono) is preserved by fallback chains in --m-font-mono. */
+@import url("https://fonts.googleapis.com/css2?family=Inter+Tight:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap");
+
 @tailwind base;
 @tailwind components;
 @tailwind utilities;
@@ -45,6 +50,37 @@
     --sidebar-border: 240 4% 12%;
 
     --radius: 0.75rem;                /* 12px */
+
+    /* ------------------------------------------------------------------
+       Modern palette (SP4 claim-drawer)
+       ------------------------------------------------------------------
+       Light, document-feeling surface tokens for the drawer. Prefixed
+       `--m-` to avoid colliding with the project's existing tokens
+       (e.g. the existing `--accent: 217 100% 56%` electric blue, used
+       via Tailwind utilities everywhere). Same prefix family as the
+       `--sidebar-*` tokens above. The drawer's component CSS will
+       reference these via `var(--m-surface)` etc.
+       Coexists with the dark app shell — the drawer is rendered on a
+       light surface regardless of global theme.
+       ------------------------------------------------------------------ */
+    --m-surface: #FAFAF7;
+    --m-ink-primary: #0A0A0A;
+    --m-ink-secondary: #6B6B6B;
+    --m-ink-tertiary: #A0A0A0;
+    --m-border-heavy: #1A1A1A;
+    --m-accent: #1D4ED8;
+    --m-accent-hover: #1E40AF;
+    --m-error: #DC2626;
+    --m-error-bg: #FEF2F2;
+    --m-success: #15803D;
+    --m-success-bg: #F0FDF4;
+    --m-warning: #B45309;
+    --m-warning-bg: #FFFBEB;
+
+    /* Modern type stack — UI sans + data mono. Fallbacks preserve the
+       existing Geist Mono face for any element that hasn't opted in. */
+    --m-font-sans: "Inter Tight", ui-sans-serif, system-ui, sans-serif;
+    --m-font-mono: "JetBrains Mono", ui-monospace, "Geist Mono", monospace;
   }
 
   * {