JSFiddle - React, Tailwind, and code Playground

HTML

<div id="par">
    <div class="inside">One</div>
    <div class="inside">Two</div>
    <div class="inside">Three</div>
</div>

CSS

#par {
    border: 1px solid red;
}

#par:before {
    margin-top: 10px;
    content: " ";
    display: table; /* if you replace the display to table 
    all we stay the same */
}

#par:after {
    content: " ";
    display: table;
    clear: both;
}

.inside {
    float: left;
    border: 1px solid blue;
}