What CSS framework do you use?

I use to use bootstrap a lot, but now I am falling in love with tailwind

I have used Bootstrap as well as Bulma for different projects.

IMO, Bootstrap has become less opinionated over time (i.e. more like Tailwind). People always said they could spot a Bootstrap site, and I think that's becoming less true.

Bulma is still easy because of sensible defaults, but the lower popularity helps it from feeling as overdone as early Bootstrap.