JSFiddle - React, Tailwind, and code Playground

HTML

<body>
      <div id="container">
        <div id="left">
          Hello
        </div>
        <div id="right">
          <div style="background-color: red; height: 10px;">Hello</div>
        </div>
        <div class="clear"></div>
      </div>
    </body>

CSS

#left
        {
          width: 200px;
          float: left;
        }
    
        #right
        {
          margin-left: 200px; /* Change this to whatever the width of your left column is*/
        }
    
        .clear
        {
          clear: both;
        }