Two Accent Colors in Ghost for Dark and Light modes

I wonder if it is possible to have two different accent colors in Ghost for dark and light modes respectively? My gut feeling says that it is possible via code injection, but I am not sure how.

Yes. Something like (not tested and will need to be updated for whatever selector your theme is using for dark mode)

body.dark {
 --ghost-accent-color: pink;
}

or maybe

@media (prefers-color-scheme: dark) {
  body {
    --ghost-accent-color: pink;
  }
}

… depending on whether you’re setting dark mode with a class or reading the browser’s preference. Either way, the idea is the same - you change the value of the variables that determine the color.