[chrismorgan]

I recently added dark mode support with a new website for myself, using (prefers-color-scheme: dark) by default, but also allowing the user to switch between light and dark mode if they have JavaScript enabled. It also supports switching image sources in dark mode, so that I can use a dark mode screenshot in dark mode, and light in light. (I haven't yet published the draft article I have using this feature.)

I wrote about it at https://chrismorgan.info/blog/dark-theme-implementation/.

[tenryuu]

SteamDB also recently added this too, but it also doesn't require JavaScript, as it's based in the cookie. The toggle does use JavaScript if you do have it enabled