Hi, all
I'm new SIG user and I have problem with CSS. Please take a look on the test website:

www.teatrpanao.pl/index.php?option=com_content&view=article&id=3:test-galerii&catid=1:news&Itemid=2

The thumbnails aren't looks so good.

I tried to change sig.css and jwsig.php files but now I don't know what should I have to do.
I know I can change this line in jwsig.php file:
I want to achieve an effect like this:

www.kmarkopoulos.gr/index.php?option=com_content&view=article&id=52:2008-07-20-16-05-58&catid=35:2008-07-20-15-46-58&Itemid=11

or this (demo galleries):

www.joomlaworks.net/content/view/17/42/

On my website I'm using rt_afterburner_j15 template.

Regards.