20 CSS clearfix hack

Use display: flow-root instead of the clearfix hack · Issue #32550 · twbs/bootstrap · GitHub

What is a clearfix? - GeeksforGeeks

Lessons Learned Concerning the Clearfix CSS Hack

Simplifying CSS With Sass

The Future of CSS: Flexbox Is a Game Changer

CSS float grids

15 Clearfix Hack

css - What methods of 'clearfix' can I use? - Stack Overflow

Floats: Something You Should Know How to Do Even Though There are Better Ways to Achieve the Same Thing., by Jenna Maaskant

display: flow-root

html - What is a clearfix? - Stack Overflow