CSS does not work on Safari, but on FF.

Hey everyone.

I have been using a chatsoftware on my website ( http://blueimp.net ) and it worked great, even with Safari. Now, I wanted to mod the chat, and added an own theme, which i downloaded from a website which hosts several templates.

I modded the template and made it fit to the actual css. The new theme, Blackbox, does work on FireFox, but appears all white and formatting-less on Safari. Why?

Here is an original theme: http://drachennetz.com/semichat/css/black.css

And here is Blackbox: http://drachennetz.com/semichat/css/blackbox.css

Can anyone help me?

Regards, Ingwie.