Mike examines the real power of CSS custom properties compared to Sass variables—they can change at runtime.
I’m convinced that in almost all cases, responsive design logic should now be contained in variables. There is a strong argument too, that when changing any value, whether in a media query or an element scope, it belongs in a variable. If it changes, it is by definition a variable and this logic should be separated from design.
A quick visual guide to CSS Grid properties and values.
Neither matters all that much and you can use every method on the same project without the universe imploding.
Some interesting approaches in the comments too.
This is a really clear explanation of how CSS works.
A whole lotta CSS properties and values gathered together in one place. The one-page view is a bit overwhelming, but search and collections can get you to the right bit lickety-split.
Harry demonstrates a really good use for CSS custom properties—allowing users to theme an interface.
I think I concur with this list. Although I guess it’s worth remembering that, given the size of the CSS spec, this isn’t an overly-long list.
It’s interesting that quite a few of them are about how things are named. It’s almost as if that’s one of the, say, two hardest things in computer science.