title: Dart polymer styling shadow root element with css
body: <p>I'm trying to style the root element of a polymer element with css. Take the counter-click for example. If I have a polymer element  in my main html and I want to give it a size (say width and height.) I try to use a global css in my main html like</p>
  
  <pre><code>click-counter{
  width:100px;
  height:100px;
  }
  </code></pre>
  
  <p>This doesn't work. </p>
  
  <p>I also tried to style inside the polymer element like</p>
  
  <pre><code>&lt;polymer-element name="click-counter" attributes="count"&gt;
    &lt;template&gt;
      &lt;style&gt;
        @host{
          click-counter {
            width:100px;
            height:100px;
          }
        }
        ...
  </code></pre>
  
  <p>This doesn't work either. Does anyone know how am I gonna style the element with css?
  (I'm using dart 0.8.1.2)</p>
  
  <p>Thanks,
  Yi</p>