JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container"><div class="float">This will work with fixed dimensions</div></div>

CSS

.container {
    width: 500px;
    height: 300px;
    background: #eee;
    position: relative;
}

.float {
    position: absolute;
    height: 50px;
    width: 150px;
    left: 50%;
    top: 50%;
    margin-left: -75px; /* Half Of Width */
    margin-top: -25px; /* Half Of Width */
    border: 1px solid #aaa;
}