CSS dark-mode on websites

I saw a nice lightning talk at the inovex office about new css features (back in the good old days without corona) - one of them was a new media query to detect light or dark mode preferences - and this is already pretty well supported

Long story short: i tested this on my website

@media (prefers-color-scheme: dark) {
  /* swap colors */ 
}

Or just with a small sass mixin

@mixin darkmode {
  @media (prefers-color-scheme: dark) {
    @content
  }
}

And if you want to know something about the preferences from javascript, this is also possible