JSFiddle - React, Tailwind, and code Playground

HTML

<div class="left">left</div>
<div class="right">
    <div class="content_both">content with style float both</div>
</div>

CSS

.left {
    float: left;
    width: 200px;
    background-color: red;
}
.right {
    margin: 0 0 0 220px;
    background-color: blue;
}
.content_both {
    clear: both;   
}