JSFiddle - React, Tailwind, and code Playground

HTML

<div>
A
</div>

<div>
B
</div>

CSS

div {
  box-sizing: border-box;
  float: left;
  width: 50%;
  background-color: red;
  min-height: 500px;
  padding: 20px;
}

div:nth-child(2) {
  background-color: blue;
}