- Add <kbd> tags to CSS property values and selectors in task descriptions
- Add solution code to all lessons for better guidance
- Improve animation contrast in transitions lesson (black/white instead
of similar purples, dramatic color changes for visibility)
- Simplify validation messages with kbd formatting
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>