JSFiddle - React, Tailwind, and code Playground
by gothic
HTML
<div class="container">
</div>
CSS
.container {
position: absolute;
top: 50%; left: 50%;
width: 300px;
height: 200px;
padding: 20px;
margin-left: -170px; /* (width + padding)/2 */
margin-top: -120px; /* (height + padding)/2 */
background: blue;
}