<div class="container">
  <div class="left"></div>
  <div class="right"></div>
</div>
html, body, .container {height: 100%;}
.left {float: left; width: 80px; height: 200px; background-color: #4688f5;}
.right {height: 100%; margin-left: 80px; background-color: yellow;}

External CSS

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External JavaScript

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