JSFiddle - React, Tailwind, and code Playground
HTML
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
</ul>
JavaScript
$("ul").on("mouseover", "li", function(){
$("ul li").css("color", "black");
$(this).css("color", "red");
});