Not OP, but which framework is the best is a very subjective question. Frameworks in general make what you want to do easier to do, at least from a developer experience perspective. Generally this meets the mark for most use-cases, but has proven to be a problem (especially in ORMs) if you want to go outside of the box. They seek to abstract complex or cumbersome logic into more consumable APIs, and in most cases this ends up being a footgun.

Point I am trying to make is: learn all the nitty gritty about CSS (specificity, box layout, selectors, etc...) and really understand how the base language works. Then go play with frameworks, figure out which ones fixes the parts you don't like, and makes the parts you do like better.

Usually these frameworks don't survive a "try to click on each element in their official demo" test in iOS Safari without glaring, visual issues, so I don't see much reason to rank them.