title: PrimeNg styleClass not change style of p-panel
body: <p>I am using primeNg. My .html and .scss file like below. But I can't give any styleClass to p-panel. What is wrong in my code?</p>
  
  <p>.html file</p>
  
  <pre><code>&lt;p-panel header="Student Info" styleClass="test"&gt;
      &lt;div class="ui-g"&gt;
        &lt;div class="ui-g-12 ui-md-3"&gt;
          &lt;div class="ui-g-12"&gt;
            &lt;b&gt;Student&lt;/b&gt;
          &lt;/div&gt;
         &lt;/div&gt;
    &lt;/p-panel&gt;
  </code></pre>
  
  <p>.scss file</p>
  
  <pre><code>.test {
    margin-top: 50px;
  }
  </code></pre>