Removing border from layout unit in PrimeFaces 3.0

jQuery UI is my favorite JavaScript widget library. I tried create JSP tag library to reuse it in my web applications. Then I switched to JSF and found the wonderful PrimeFaces implemented via jQuery UI. What a smart combination!

But, as always, we need a little hack to make it works as we want. My first hacking is to hide the border in layout unit. After examined with firebug, I found the border is produced by "ui-widget-content". Therefore we can overwrite layout unit's border. PrimeFaces changed its layout unit css class name to "ui-layout-pane-north", "ui-layout-pane-west","ui-layout-pane-east" and "ui-layout-pane-center".

Therefore, to remove header layout unit using css multiple class selectors: