JSFiddle - React, Tailwind, and code Playground

HTML

<div id='black' style='float: left'></div>
<div style='float: left'>
  <div id='red' style='float: left'></div>
  <div class="clr"></div>
  <div id='green' style='float: left'></div>
<div>

CSS

div {width:100px;height:10px;}

div#black{background:black}
div#red{background:red}
div#green{background:green}
div.clr{clear: both}