Fix spacing for very small screens

See merge request !2

Add dark mode

See merge request !1

This prevents all languages shown at once with javascript disabled.

Palette identical to speakers' file drop and based on catppuccin.

Minor changes to the homepage French translation

Restructure; Refer to more services

I can't be bothered to fiddle with the server's cache settings,
and it doesn't matter anyway.

No need for it if we're going to be moving to GitHub Pages

Add french translation and update for 36c3