JSFiddle - React, Tailwind, and code Playground

HTML

<div class="what">
<div></div>
</div>

<div>

</div>

CSS

.what{
  min-height: 500px; 
  background-color:yellow; 
}

.what div{
  min-height:200px; 
  max-width: 300px; 
  background-color: black; 
  position:fixed; 
  top: 280px; 
}