JSFiddle - React, Tailwind, and code Playground

HTML

<div class="top">
    
    <div class="left">
        <pre>
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
        </pre>
    </div>

    <div class="right">
        <pre>
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
Some code long code to display with scrollbars!
        </pre>
    </div>
    
</div>

CSS

.top {
    width: 350px;
    height: 150px;
    border: 1px solid #000000;
    overflow: auto;
    float: left;
    clear: both;
}

.left {
    width: 50%;
    float: left;
    text-align: left;
    overflow: auto;
}

.right {
    width: 50%;
    float: right;
    text-align: left;
    overflow: auto;
}