JSFiddle - React, Tailwind, and code Playground

HTML

<div class="tudo"></div>
<div class="bottom">This is fixed here</div>

CSS

body{
  margin:0;
}
.bottom{
  width:100%;
  height: 50px;
  position: fixed;
  bottom:0;
  background-color: black;
  margin:0;
  text-align:center;
  color:white;
  padding:0;
}
.tudo{
width:100%;
height:2000px;
}