JSFiddle - React, Tailwind, and code Playground

HTML

<div class="outer">
  <div class="inner red"></div>
  <div class="inner green"></div>
</div>

CSS

div {
  height: 50px;
}

.outer {
  width: 200px;
}

.inner {
  display: inline-block;
  width: 50%;
}

.red {
  background-color: red;
}

.green {
  background-color: green;
}