title: 320 and up mobile framework - Why stylesheets starts at 480?
body: <p>I've just download <a href="http://stuffandnonsense.co.uk/projects/320andup/" rel="noreferrer">320 and up</a> for responsive design, the stylesheets are divided as follows:</p>
  
  <ul>
  <li>480.css</li>
  <li>600.css</li>
  <li>768.css</li>
  <li>992.css</li>
  <li>1382.css</li>
  </ul>
  
  <p>And print.css, style.css and 2x.css</p>
  
  <p>I don't understand why isn't a 320.css stylesheet, or I should use style.css for that resolution?</p>