feat: enhance GitHub Pages landing page with improved code block styling and red accent theme

- Add line numbers, syntax highlighting, and indent rainbow to configuration code block
- Replace purple/pink theme with sleek dark blue/slate background
- Update all accent colors from blue to red/orange tones for warmer aesthetic
- Modernize color scheme: red-400, orange-400, rose-400, amber-400, pink-400
- Update hero gradient, CTA buttons, stats cards, and feature icons
- Maintain emerald/teal for MIT license and mutations category

Author: Gary Wenneker