title: CSS: height- fill out rest of div?
body: <p>i wonder if this is possible with simple css or if i have to use javascript for this?</p>
  
  <p>i have a sidebar on my website. a simple div#sidbar it's normally about 1024px high, but the height changes dynamically due to it's content.</p>
  
  <p>so let's imaginge the following case:</p>
  
  <pre><code>&lt;div id="sidebar"&gt;
     &lt;div class="widget"&gt;&lt;/div&gt; //has a height of 100px
     &lt;div class="widget"&gt;&lt;/div&gt; //has a height of 100px
     &lt;div id="rest"&gt;&lt;/div&gt; //this div should have the rest height till to the bottom of the sidebar
  &lt;/div&gt;
  </code></pre>
  
  <p>i want the div#rest to fill out the rest of the sidebar till it reaches the bottom of the div#sidebar.</p>
  
  <p>is this possible with pure css?</p>