I have a Sass-driven site I’ve inherited. There’s a `variables.scss` file that defines a bunch of color and media size and other variables; makes sense. But now I want to basically overwrite all those variables with new values for dark-mode purposes. Is there a way to easily do this in Sass?

(Assume I have DDGed `sass dark mode` and none of the first dozen hits seemed to be relevant to this kind of situation, either because they aren’t or because I don’t speak Sassafrassh and so misunderstood.)