title: Size of div depending on size of another div
body: <p>I got a div which contains 2 other divs. They are vertically aligned. Now, the lower div is changing its size via javascript. What I want now is that the upper div is changing its size depending on the other divs size. Is there a way to do this with css style only, without using js?</p>
  
  <p>UPDATE: The outer div has a fixed size.</p>
  
  <pre><code>&lt;div&gt;
   &lt;div&gt; childdiv 1&lt;/div&gt;
   &lt;div&gt; childdiv 2&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>UPDATE: Ok I didnt make this clear enough, the lower box is changing its height in top direction. And the upper div should then decrease its height.</p>