JSFiddle - React, Tailwind, and code Playground

HTML

<div class="a">
    This is the A div
    <div class="b">
        This is the B div
    </div>
</div>

CSS

.a {
    background-color: red;
    width: 100px;
    height: 100px;
    position: relative;
}

.b {
    background-color: blue;
    width: 100px;
    height: 100px;
    position:absolute;
    top: 50px;
    left: 50px;
}

JavaScript

$('.a').hover(function() {
   alert('mouseenter'); 
}, function() {
   alert('mouseleave');
});