JSFiddle - React, Tailwind, and code Playground

HTML

<div class=container>
  <div class="child"></div>
</div>

CSS

.container {
  display: flex;
  height:100vh;
  background:Peachpuff;
}

.child{
  height:100px;
  width:100px;
  margin: auto;
  background: Aquamarine;
}