title: Sass variables and gradient
body: <p>Hy everyone!
  I want to use Sass variables with in a Vaadin 7.1.0 project for a linear gradient background, but some reason it doesn't work.
  The code:</p>
  
  <pre><code>$topBarDarkBlue: #5F7FB7;
  $topBarLightBlue: #8EABE1;
  
  .title {
      background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, $topBarDarkBlue),
      color-stop(100%, $topBarLightBlue));
      background-image: -moz-linear-gradient(bottom, $topBarLightBlue 0%, $topBarDarkBlue 100%);
      width: 100%;
      height: 70px;
  }
  </code></pre>
  
  <p>It seems to be correct, but why it doesn't work?</p>