JSFiddle - React, Tailwind, and code Playground

HTML

<div class="layout">
    <div class="width">
      <div class="area left">
        
      </div>
      <div class="area right">

      </div>
    </div>
  </div>

CSS

.layout {
  box-sizing: border-box;
  padding-left: 250px;
  padding-right: 250px;
  padding-top: 50px;
}

.layout .area.left, .layout .area.right {
  display: inline-block;
  height: 250px;
}

.layout .area.left {
  width: 400px;
  background: green;
}

.layout .area.right {
  width: 600px;
  background: blue;
}

.width {
  width: 1000px;
  margin: 0 auto;
}