JSFiddle - React, Tailwind, and code Playground

HTML

<div id="summary">Sample</div>
<div id="detail">Detail of theis summary</div>

CSS

#summary {
    background: #666;
    width: 100px;
    color: #fff;
}

#summary:hover {
    cursor: pointer;
    color: #fff200;
}

#detail {
    width: 300px;
    height: 300px;
    background: #fff200;
    display: none;
}

JavaScript

$(document).ready( function(e) {
    $('#summary').hover( function( evt ) {
        $('#detail').toggle();
    });
});