title: CSS Selector on custom element
body: <p>Is there any contraindications on stylizing Angular2 custom element directly and selecting them with CSS selector ?</p>
  
  <p>Example : </p>
  
  <pre><code>// HTML
  &lt;My-Page&gt;
      &lt;header&gt;&lt;/header&gt;
      &lt;main&gt;&lt;/main&gt;
      &lt;My-Footer class="sticky-footer"&gt;&lt;/My-Footer&gt;
  &lt;/My-Page&gt;
  
  // CSS 
  My-Page {
      background-color: grey;
  }
  
  header {
      ...
  }
  
  .sticky-footer {
      position: absolute;
  }
  </code></pre>
  
  <p>Good or bad practice ? </p>