Board colors changed to Chess.com-style green:
- Light squares: #EBECD0 (cream/beige)
- Dark squares: #779556 (olive green)
- Selected: yellow highlight
- Last move: yellow tint

Board frame:
- Dark border (3px #3d3d3d)
- Deeper shadow for elevation
- 6px border-radius

Pieces:
- Larger font-size (62px max)
- Drop-shadow filter for 3D depth
- Hover scale effect (1.05x)
- Removed pulsing animation on legal moves (static dots like Chess.com)

Highlights:
- Stronger check glow (red inset shadow)
- Clean static legal move dots (no pulse)
- Capture ring slightly larger (88%)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>