CodePen Embed - ExQLEyK

<div class="main">
  <div class="sidebar" >
    <ul>
      <li>hello world</li>
      <li>hello world</li>
      <li>hello world</li>      
    </ul>
    
  </div>
  <div class="content">
    <p>
      Flexbox is really cool if you know how to use it
    </p>
    <div>
      <img src="https://placekitten.com/400/300" />
    </div>
  </div>
</div>

.main {
  display: flex;
}

.sidebar {
  flex: 0 0 300px;
}

.content {
  flex: 1;
}

This Pen is owned by Ynon Perek on CodePen.

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