Forum:Tabber help anyone?

so we were trying to make the tabbers rounded on http://camphalfbloodroleplay.wikia.com/wiki/MediaWiki%3AWikia.css this wiki, but it still comes up square, however on my sand box wiki, they come up round

see http://bachs-epic-thinking-zone.wikia.com/wiki/MediaWiki:Wikia.css

http://bachs-epic-thinking-zone.wikia.com/wiki/User:Mr.Mikachu/wikia.css

and

http://bachs-epic-thinking-zone.wikia.com/wiki/Lucas_Vonner

I'm not sure what I'm doing wrong that it works on one wiki and not another >.<