An interesting framework that I saw here on HN a couple of days ago is Tailwind UI (https://tailwindui.com/). It's not out just yet but looks very promising.
Other than that I would recommend Bulma (https://bulma.io/). It's like bootstrap but with a different philosophy on how CSS should be implemented.
Also, it doesn't include any javascript. I think that was a good decision on their part as you won't have to fight the default behaviors on their components if you want to do something slightly different.
This is incorrect advice. Tailwind is a utility CSS framework, and Tailwind UI is literally a collection of prewritten HTML for you to use and edit, that uses Tailwind classes.
> Tailwind UI is a collection of professionally designed, pre-built, fully responsive HTML snippets you can drop into your Tailwind projects.
Other than that I would recommend Bulma (https://bulma.io/). It's like bootstrap but with a different philosophy on how CSS should be implemented. Also, it doesn't include any javascript. I think that was a good decision on their part as you won't have to fight the default behaviors on their components if you want to do something slightly different.