JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

html{
    min-height: 100%;
    display: flex;
    justify-content:center;
	  align-items: center;
}

body{
  display: flex;
	justify-content:center;
	align-items: center;
}

div{
  width: 200px;
  height: 200px;
  background: green;
}