JSFiddle - React, Tailwind, and code Playground

HTML

<div id="main">
    <div id="subdiv"> <span>
            Some Text
        </span>
    </div>
</div>

CSS

#main {
    height: 300px;
    border:2px solid green;
    width:100%;
    overflow:auto;
}
#subdiv {
    width:90%;
    height:90%;
    border: 2px solid red;
}