JSFiddle - React, Tailwind, and code Playground

HTML

<div id="content">
  <div id="sidebar">some sidebar content</div>
  <div id="main">some main contentsome main contentsome main contentsome main contentsome main contentsome main contentsome main contentsome main contentsome main contentsome main contentsome main content</div>
</div>

CSS

#sidebar, #main {
    display: table-cell;
}

#sidebar {
    width:100px;
    float: left;
    background:red;
}

#main {
    background: blue;

}