Semantic UI
Another contender in the race is Semantic UI, which tries to distinguish itself with a lot of themes and customization. There are more than 3000 theming variables, which results in a massive breadth. Or so the docs say.
Bootstrap 4 kind of covers all this and is fully customizable as well, but one advantage with Semantic UI is that it results in nice-looking layouts by default. Still, it’s not the best-looking out of the box, which is why it is down on the list.
It also has one of the steepest learning curves, and coding conventions are much more strict. Try it; I’d say, and see if it looks like something you might prefer.
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