You don’t need to “use” anything, browsers have very good CSS support these days.
Sure, but you don't want to import CSS Franeworks as precomiled files, don't you? You would like to use them in their packaging system. This seems to be more js-centric today, still lots of SASS.
the project had some sass i didn’t want to port back to css. i’m using dartsass to compile it to css which is a recommendation in the rails guide.