title: Making CSS url() relative to document
body: <p>When it comes to CSS the following rule applies:</p>
  
  <pre><code>Partial URLs are interpreted relative to the source of the style sheet,
  not relative to the document.
  </code></pre>
  
  <p>But here's my problem :</p>
  
  <p>I have different websites that use the same CSS file. While they use the same layout, the actual images the CSS references are different for each one of them.</p>
  
  <p>Exemple:</p>
  
  <pre><code>#header {
  width: 960px;
  height: 200px;
  background: url(/images/header.png);
  }
  </code></pre>
  
  <p>Each domain has its own "images" folder and its own "header.png" that I would like the CSS to reference. Currently it behaves as it's supposed to and tries to find the png file on the domain where the CSS is hosted. What I want is for it to get the png file from the domain where the CSS file was called.</p>
  
  <p>I use "link" for the stylesheets because "@import" breaks progressive rendering in IE. </p>
  
  <p>Any suggestion or workarounds?</p>