title: CSS regression tool?
body: <p>I'm looking for a visual regression testing tool for CSS refactoring and see whether or not there are any unintended cascading behavior in a website. </p>
  
  <p>Ideally, the tool that can crawl a website (even locally) and grab snapshots of each page and store it in a single repository. </p>
  
  <p>When run for the second time, it will show the pages that are visually different since the last time it was run.</p>
  
  <p>Even better:</p>
  
  <ol>
  <li>if it can show the overlapper XOR view of the 2 version of the page.</li>
  <li>compare rendering results of different browsers (almost like an automated Microsoft Expression Web compare feature).</li>
  </ol>