JSFiddle - React, Tailwind, and code Playground

HTML

<div id="absolute">
    <div class="centerd">
    <h1>helo</h1>
    <span>hi again</span>
    </div>
</div>

CSS

#absolute {
    position:absolute;
    top:10px;
    left:10px;
    width:50%;
    height:50%;
    background:yellow;
}

.centerd {
    display:table-cell;
    vertical-align:middle;
}