[feature request]: Dark mode

[jimmywarting]

Is your feature request related to a problem? Please describe.

site is too bright at night

Describe the solution you would like.

For the website to support dark mode and hopefully also make use of color-scheme with either of this solutions:

<meta name="color-scheme" content="dark light">

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
  }
}

Describe alternatives you have considered.

No response

Requisites

• I performed a cursory search of the issue tracker to avoid opening a duplicate issue.
• I understand that not filling out this template correctly will lead to the issue being closed.

Additional content

https://web.dev/color-scheme/