title: Why is my div not taking up 100% height of its parent container?
body: <p>Bit confused here. I am quite tired, so I'm sure I'm making a silly mistake but here's my HTML/CSS:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.CAContainer {
    display: flex;
    flex-flow: row nowrap;
    justify-content: flex-start;
    align-items: center;
    margin: 0;
    padding: 0;
  }
  .CASideBorder {
    height: 100%;
    background: #000;
    width: 8px;
  }
  .CAMiddleContainer {
    display: flex;
    flex-flow: column nowrap;
    justify-content: center;
    align-items: center;
  }
  .CATopBorder {
    height: 8px;
    background: #000;
    width: 100%;
  }
  .CAMiddleTextContainer {
    padding: 40px 80px 40px 80px;
    font-size: 4em;
    color: #000;
  }
  .CABottomBorderContainer {
    display: flex;
    flex-flow: row nowrap;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    height: 8px;
  }
  .CABottomBorderLeft,
  .CABottomBorderRight {
    flex: 1;
    height: 100%;
    background: #000;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="CAContainer"&gt;
    &lt;div class="CASideBorder" id="CALeftBorder"&gt;&lt;/div&gt;
    &lt;div class="CAMiddleContainer"&gt;
      &lt;div class="CATopBorder"&gt;&lt;/div&gt;
      &lt;div class="CAMiddleTextContainer"&gt;
        text
      &lt;/div&gt;
      &lt;div class="CABottomBorderContainer"&gt;
        &lt;div class="CABottomBorderLeft"&gt;&lt;/div&gt;
        &lt;div class="CABottomBorderRight"&gt;&lt;/div&gt;
      &lt;/div&gt;
    &lt;/div&gt;
    &lt;div class="CASideBorder" id="CARightBorder"&gt;&lt;/div&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>And the <a href="https://jsfiddle.net/c4ycp72q" rel="nofollow noreferrer">fiddle</a>.</p>
  
  <p>Shouldn't <code>CASideBorder</code> be taking up 100% of its parent container, which has its height calculated by the text size and padding of <code>CAMiddleTextContainer</code>? Am I missing something really obvious here? Any help is appreciated.</p>