There are a lot of CSS frameworks out there and this is by no means an exhaustive list. Checkout the project on github to get an idea of popularity and how maintained it is. Also, look at the project documentation and make sure it makes sense to you.
- Bootstrap
- Bulma
- Materialize CSS
- Foundation
- Pure CSS
- Material Design Lite
- Semantic UI
- Baseguide
- Siimple
- Skeleton CSS
- Turret CSS
- uikit
If there is another CSS framework that you think should be listed here, please open a pull request.