title: Does Gmail support CSS classes?
body: <p>The title is really just the shortened version of the question. I'm aware of Gmail's limited CSS support, but I was reading <a href="http://www.campaignmonitor.com/css/" rel="nofollow">"Guide to CSS support in email"</a>, which has a note for Gmail's support of <code>.class</code> and <code>#id</code> selectors:</p>
  
  <blockquote>
    <p>(!) Works in some instances if CSS is inlined before or during campaign import</p>
  </blockquote>
  
  <p>What does this actually mean as far as CSS support is concerned? To me, it sounds like it's just suggesting to use a preprocessor to take any style declarations and apply them to the matched elements.</p>
  
  <h3>Is there a trick to being able to use CSS classes in an HTML email in the Gmail client?</h3>