How to vertically center .div in Bootstrap?

Question

css

How to vertically center a black and yellow .div inside a red one? I can't find how to do this in Bootstrap. Do you need to write your own class? What is the best way to do this without breaking anything in Bootstrap (surely there is some best practice)?
codepen.io/dhatt/pen/KgzoGx

Answer 1

codepen.io/cyberbober/pen/dprmAp

Answer 2

In my opinion, you can’t align vertically through classes in bootstrap. You need to set the css yourself.