Board Thread:Support Requests - Getting Started/@comment-4594870-20140803111314/@comment-5558012-20140803144944

Try:

@import url("http://monsterhigh.wikia.com/index.php?title=MediaWiki:Common.css&usemsgcache=yes&ctype=text/css&smaxage=86400&action=raw&maxage=86400");

Staff should be able to do this for you though. They imported the Common.css to the Wikia.css on the back end without me even asking.