feat: compact icon-sized cards, timer overlay, more transparent backdrop

[Rubyj]

Changes

1. Compact cards

• Card size reduced from 100×72 → 52×52
• Card padding reduced from 6 → 2px
• Icon size increased from 44 → 48px (fills nearly the entire cell)
• Class colour strip thinned from 3 → 2px

2. Timer overlays icon

• Timer/Ready label moved from below the icon to centered on top of it
• Font size bumped 12 → 14pt for readability over the icon texture

3. More transparent backdrop

• Main frame backdrop: 0.55 → 0.35 alpha
• Title bar: 0.65 → 0.45 alpha
• Per-row card background: 0.35 → 0.20 alpha