Admin Theme New Sections:
- 📐 Spacing & Layout: 9 range sliders for border-radius, content-max,
  header-h, nav-bottom-h, card-padding, section-gap, touch-min
- 🎲 Domino: 5 color pickers for game theming
- 🎯 Backgammon: 8 color pickers for board/checker/felt colors
- 🎨 Icons Grid: per-icon upload (31 icons individually replaceable)

RGBA Picker:
- Color input + alpha slider (0-100%) for rgba-based CSS variables
- Live preview, outputs rgba() string
- Applied to: board highlights, overlays, borders

Per-Icon Override:
- Individual SVG/PNG upload per icon
- Runtime: replaces SVG <use> with <img> element
- Resolution guide: "24×24px SVG مفضل"

Upload Resolution Guides:
- Pieces: 128×128px
- Logo: 200×40px
- Favicon: 32×32px
- Icons: 24×24px
- Sprite: SVG 24px viewBox

All changes live-effective via CSS variable injection + runtime JS.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>