feat(phase-4): visual polish — font stack, shadow system, transitions, micro-interactions

Phase 4: Visual Polish

4.1 Font Stack Upgrade:
- Add --font-display token for headings
- Replace all hardcoded font-family: monospace with var(--font-mono)
- Replace hardcoded 'Segoe UI' stack with var(--font-body)

4.2 Shadow Elevation System:
- Add --shadow-2xl, --shadow-card/dropdown/modal/toast/header/dark-lg tokens
- Replace hardcoded shadows in header, menu, banner, shared, recipe-modal,
  progress-panel, import-modal, alphabet-bar with semantic tokens
- Add dark theme shadow overrides with increased opacity

4.3 Transitions & Micro-interactions:
- Replace transition: all with specified properties (performance)
- Use --transition-fast/base/slow tokens instead of hardcoded 0.2s/0.3s
- Add :active scale feedback to modal buttons
- Enhance card hover with box-shadow + border-color lift

4.4 Dark Theme Refinement:
- Elevated shadow opacity for dark theme visibility

4.5 Density:
- Standardize container padding with --space-2 token

21 files changed

static/css/components/card.css

@@ -19,7 +19,7 @@
     border: 1px solid var(--lora-border);
     border-radius: var(--border-radius-base);
     backdrop-filter: blur(16px);
-    transition: transform 160ms ease-out;
+    transition: transform var(--transition-fast) ease-out, box-shadow var(--transition-fast) ease-out, border-color var(--transition-fast) ease-out;
     aspect-ratio: 896/1152; /* Preserve aspect ratio */
     max-width: 260px; /* Base size */
     min-width: 200px; /* Prevent cards from becoming too narrow */
@@ -33,7 +33,8 @@
 
 .model-card:hover {
     transform: translateY(-2px);
-    background: oklch(100% 0 0 / 0.6);
+    box-shadow: var(--shadow-md);
+    border-color: var(--lora-accent);
 }
 
 .model-card:focus-visible {