The theme picker lists Modern (the old Dark and Light), Classic and six new
palettes, from Dracula's spec (with Alucard), Material 3's baseline scheme,
libadwaita's CSS variables, Flat Remix's _colors.scss, Paper and Nord. A second
setting picks Light, Dark or Auto where a theme has both; Classic and Paper do
not, so it is hidden for them.
The page gets data-mode, light or dark, and Auto is worked out in theme.ts from
the system, so each palette is written once instead of again under a media
query. Every new palette clears WCAG AA for text on its backgrounds. An old
ipx.theme of dark, light or auto carries over as Modern.
Closes#27.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>