JSFiddle - React, Tailwind, and code Playground

HTML

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

CSS

.parent {
    position: absolute;
    height: 500px;
    width: 100%;
    background: green;
}

.child {
    position: absolute;
    top: 50%;
    left: 50%;
    background: blue;
    height: 100px;
    width: 100px;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
    -moz-transform: translate(-50%, -50%);
    -o-transform: translate(-50%, -50%);
}