JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <div id="left">Alpha</div>
    <div id="right">Bravo</div>
</div>

CSS

#wrapper {
    background-color:grey;
    border-top: 1px solid black;
    border-botton: 1px solid black;
    padding:10px;
    overflow : hidden;
}
#left {
    background-color:yellow;
    float:left;
}
#right {
    background-color:pink;
    float:right;
}