- Replace custom highlight styles with @codemirror/theme-one-dark
- Cleaner implementation with official CodeMirror theme
- Keep custom font and padding overrides
- Replace textarea with CodeMirror 6 for syntax highlighting
- Add Emmet abbreviation expansion (Tab to expand)
- Support HTML and CSS language modes with autocomplete
- Add dark theme matching app design
- Tab indentation with Shift-Tab for outdent
- Update help modal with Emmet shortcuts
