JSFiddle - React, Tailwind, and code Playground

HTML

<a onmouseover="document.getElementById('div_name').style.display='';" 
onmouseout="document.getElementById('div_name').style.display='none';" 
href="" onclick="return false;" 
style="text-decoration:none;border-bottom:1px dotted blue;">
Show more...</a>
<br />
<div id="div_name" style="display:none;margin:15px 15px 0px 15px;
  padding:5px;border:1px solid #aaa;">
This is more information placed in our hidden div.  
When you move your mouse off the link above this DIV area will 
disappear.
</div>