JSFiddle - React, Tailwind, and code Playground

HTML

<div id="parent">
  <div id="child"></div>
</div>

CSS

#parent {
  position: fixed;
  width: 600px;
  height: 300px;
  background: red;
}

#child {
  position: relative;
  width: 200px;
  margin-bottom: 10px;
  margin-top: 10px;
  height: auto;
  background: blue;
}