JSFiddle - React, Tailwind, and code Playground

HTML

<div id="red"></div>
<div id="blue"></div>

CSS

#red, #blue {
    position: absolute;
    width: 100px;
    height: 100px;        
}
div:hover, 
.yellow {
    background-color: yellow !important;
}
#red {
    background-color: red;
}
#blue {
    background-color: blue;
    top: 50px;
    left: 50px;
}

JavaScript

$('div').hover(function() {
    $('div').addClass('yellow');
});

$('div').mouseleave(function() {
    $('div').removeClass('yellow');
});