:root.darkmode {
  filter: invert(1) hue-rotate(.5turn);
}

:root.darkmode :is(img, iframe, video, .adsbygoogle) {
  filter: invert(1) hue-rotate(.5turn);
}

:root.darkmode img:not(:hover) {
  opacity: .7;
  transition: opacity .25s ease-in-out;
}