JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bigdiv">
<div class="smalldiv"></div>
</div>

CSS

.bigdiv{
height:100%;
width:100%;
background-color:#eee;
}
.smalldiv{
height:400px;
width:1024px;
background-color:#ccc;
    margin:auto;
}