I used to use Sass a lot — especially when I was working on extremely complicated CSS codebases as a consultant. Sass definitely is not “dead” either — tech doesn’t die, it’s 1s and 0s — it’s extremely useful still!
Sure, CSS is bringing stuff like nesting and mixins over from Sass, but it doesn’t mean Sass is useless or “replaced”. I personally don’t use Sass anymore because I don’t need to but if the needs were there, I would use it in a heartbeat.
Stuart’s guide here on when and where to use custom properties and/or Sass variables is great because — as the title suggests — it’s pragmatic. Stuart knows his stuff too. He’s an expert CSS and design systems consultant and has worked on huge systems, so you know this knowledge comes from deep experience.
Check it out