JSFiddle - React, Tailwind, and code Playground

HTML

<div id="document"></div>
<footer></footer>

CSS

#document{
    width:100%;
    height:1200px;
}
footer{
    width:100%;
    height:50px;
    background-color:black;
    position:fixed;
    top:100%;
    left:0;
    margin-top:-50px;
}