httpd: add a "dark mode" in directory listings and error pages

Introduce a new "dark mode" for httpd(8) directory listings and error pages,
using the prefers-color-scheme css function. It uses the colorscheme already
used in OpenBSD project websites.

This version will only be displayed if the user's browser specifically sends
a "prefer darker themes if available" request.

Input from florian@, danj@ and clematis.

OK florian@, danj@ (on a previous version with the wrong background color)

0 files changed, 0 insertions, 0 deletions