title: how to change style of primefaces component
body: <p>how change the style of primefaces components.
  especially the background color of <code>&lt;p:layoutUnit</code>.</p>
  
  <p>this is my code :</p>
  
  <pre><code>&lt;p:layout fullPage="true"&gt;
          &lt;!-- TITRE --&gt;
          &lt;p:layoutUnit position="north" size="auto" resizable="true" closable="true"  &gt;
              &lt;ui:include src="titre.xhtml"&gt;&lt;/ui:include&gt;
          &lt;/p:layoutUnit&gt;
          &lt;!-- CONTENT --&gt;
          &lt;p:layoutUnit position="center" size="25%" header="Options" &gt;
                  &lt;ui:include src="titre.xhtml"&gt;&lt;/ui:include&gt;
          &lt;/ui:include&gt;
      &lt;p:layout fullPage="true"&gt;
  </code></pre>