This is the website: clashjeans.se/test/styles.html
No offence but wouldn't it be easier just to implement a simple light-box script? Or maybe it doesn't fill you requirements?
How much can I modify lightbox? Is it possible to use css to links and images? If it isn't possible I don't think it will work for me.
check out http://flowplayer.org/tools/index.html
I think what you're wanting to do is something like using tabs for your root categories and scrollable for the internal photos.