title: Div should fill parent height
body: <p>I am trying to make a DIV fill its whole parent container with pure CSS. <code>height:100%</code> doesn't do it and flexbox or <code>display:table</code> on the parent also didn't help :(</p>
  
  <p>In the attached code, we're talking about the innermost
  <code>div.CodeMirror</code></p>
  
  <p>The problem occurs in the latest Safari on MacOS. In Chrome all is fine.
  <div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>html, body, #root {
      margin: 0; 
      padding: 0; 
      height: 100%; 
  }
  
  .App {
      display: flex;  
      flex-flow: column;  
      height: 100%; 
  }
  
  div.editorContainer {
      flex: 1 1 auto; 
      display: flex; 
      margin-bottom: 1em;
  }
  
  div.ReactCodeMirror {
      padding: 5px;  
      width: 100%; 
      background-color: #ddf;
  }
  
  .CodeMirror {
      height: 100%; 
      border: 1px solid #ccc;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet"/&gt;
  
  &lt;div id="root"&gt;
      &lt;div class="App"&gt;
          &lt;nav class="navbar navbar-default"&gt;&lt;/nav&gt;
          &lt;div class="editorContainer"&gt;
              &lt;div style="background-color: #aaf; width: 160px;"&gt;Side bar&lt;/div&gt;
              &lt;div class="ReactCodeMirror"&gt;
                  &lt;div class="CodeMirror"&gt;Should fill light blue area&lt;/div&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>