JSFiddle - React, Tailwind, and code Playground

HTML

<!--text element on page with a div id around it-->
<div id="a">hover me</div>   

<!--div that should appear added in the Custom CSS & HTML section-->
<div id="b"> ta da </div>

CSS

/* added in the Custom CSS & HTML section */

#b{
  display: none;
}



#a:hover {
  background: #abc;
}

#a:hover + #b {
  display: block;
}