JSFiddle - React, Tailwind, and code Playground

HTML

<body>
	<div id="a"></div>
	<div id="b"></div>
	<div id="c"></div>
</body>

CSS

#a{
	width:50px;
	height:50px;
	background: red;
}
#b{
	width:50px;
	height:50px;
	background: green;
	display:none;
}
#c{
	width:50px;
	height:50px;
	background: black;
}
#a:hover #b{
	display: block;
}