K2 css

Hi There,

I have added the K2 2.5 version to my installation.
Now I created a menu link which points to a K2 item. However, the result does not look like on your demo.
Is there any css file which I need to include?

Got the same problem with gk_sporter for joomla 1.7.
It would be nice to know what files exactly to copy to get something else than the default k2 default.
Hope someone can help.
Thanks