title: Positioning DIVs to the sides of a centered container
body: <p>I have a main container DIV for the content of my page, that is horizontally centered:</p>
  
  <p>HTML:</p>
  
  <pre><code>&lt;div id="master_container"&gt;
    .. my content here ...
  &lt;/div&gt;
  </code></pre>
  
  <p>CSS:</p>
  
  <pre><code>#master_container {width: 960px; margin: 0 auto;}
  </code></pre>
  
  <p>Client wants to have adverts at both sides of the page, outside of the master_container. I tried various CSS to try and position those divs but when window is resized, they overlap with the master_container. Also, I am asked to have them float when the page is scrolled.</p>
  
  <p>Can anyone please direct me to the correct solution? Thanks in advance...</p>