JSFiddle - React, Tailwind, and code Playground
by refhat
HTML
<div id="outernav">
<div id='nav'></div>
</div>
CSS
#outernav{overflow:hidden;border:2px solid #000000;height:120px;width:120px}
#nav{width:100px;height:100px;background:red;display:none;}
JavaScript
$(function() {
$("#outernav").mouseover(function() { $("#nav").css('display','block').fadeIn("slow"); });
})