anchor.diff:      }
       header table th, header table td {
           padding:4px 6px;
  +    }
  +    nav {
  +        display:block;
  +        padding:12px 12px;
  +        border-bottom:1px solid #000000;
  +        background-color: #444444;
  +        background-image: -webkit-gradient(linear, left top, left bottom, from(#444444), to(#222222)); /* Safari 4+, Chrome */
  +        background-image: -webkit-linear-gradient(top, #444444, #222222); /* Chrome 10+, Safari 5.1+, iOS 5+ */
  +        background-image:    -moz-linear-gradient(top, #444444, #222222); /* Firefox 3.6-15 */
  +        background-image:      -o-linear-gradient(top, #444444, #222222); /* Opera 11.10-12.00 */
  +        background-image:         linear-gradient(to bottom, #444444, #222222); /* Firefox 16+, IE10, Opera 12.50+ */
  +    }
  +    nav a {
  +        color:#ffffff;
  +        text-decoration:none;
  +        padding:4px 16px;
  +        border-radius:16px;
  +    }
  +    nav a:hover {
  +        background-color: #666666;
  +        background-image: -webkit-gradient(linear, left top, left bottom, from(#666666), to(#444444)); /* Safari 4+, Chrome */
  +        background-image: -webkit-linear-gradient(top, #666666, #444444); /* Chrome 10+, Safari 5.1+, iOS 5+ */
  +        background-image:    -moz-linear-gradient(top, #666666, #444444); /* Firefox 3.6-15 */
  +        background-image:      -o-linear-gradient(top, #666666, #444444); /* Opera 11.10-12.00 */
  +        background-image:         linear-gradient(to bottom, #666666, #444444); /* Firefox 16+, IE10, Opera 12.50+ */
  +    }
  +    nav a.selected {
  +        color:#000000;
  +        background-color: #efefef;
  +        background-image: -webkit-gradient(linear, left top, left bottom, from(#efefef), to(#cfcfcf)); /* Safari 4+, Chrome */
  +        background-image: -webkit-linear-gradient(top, #efefef, #cfcfcf); /* Chrome 10+, Safari 5.1+, iOS 5+ */
  +        background-image:    -moz-linear-gradient(top, #efefef, #cfcfcf); /* Firefox 3.6-15 */
  +        background-image:      -o-linear-gradient(top, #efefef, #cfcfcf); /* Opera 11.10-12.00 */
  +        background-image:         linear-gradient(to bottom, #efefef, #cfcfcf); /* Firefox 16+, IE10, Opera 12.50+ */
       }
       .frames {
           width:50%;
  
positive.code:             <% end %>
          </table>
      </header>
      <section class="backtrace">
          <ul class="frames">
              <% backtrace_frames.each_with_index do |frame, index| %>
  
negative.code:     }
      header {
          padding:32px 32px;
          border-bottom:1px solid #e64c38;
          background-color: #ffe5e7;
          background-image: -webkit-gradient(linear, left top, left bottom, from(#ffe5e7), to(#ffb2b8)); /* Safari 4+, Chrome */
          background-image: -webkit-linear-gradient(top, #ffe5e7, #ffb2b8); /* Chrome 10+, Safari 5.1+, iOS 5+ */
  