JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bigDiv">
    <div class="smallDiv">
    </div>
</div>

CSS

.bigDiv {
    width:200px;
    height:200px;
    background-color:#efefef;
    position:relative;
}
.smallDiv {
    width:50px;
    height:50px;
    background-color:#cc0000;
    position:absolute;
    top:50%;
    left:50%;
    transform:translate(-50%, -50%);
}