JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
  <div class="child">
    Foo Bar!
  </div>
</div>

CSS

.wrapper {
  background-color: grey;
  min-height: 50vh;
}

.child {
  height: 100%;
  background-color: blue;
  color: white;
}