JSFiddle - React, Tailwind, and code Playground

HTML

<body>
	<div class="hoverbox">
	</div>
	
	<div class="showbox">
	</div>

</body>

CSS

.hoverbox {
		background-color:red;
		width:20px;
		height:20px;
	}
	
	.showbox {
		width:20px;
		height:20px;
	}

JavaScript

$('.hoverbox').hover(function() {
		$('.showbox').css("background-color", "green");
	});