jQuery Demo Doesn't Work On My Browser

jQuery Demo Doesn't Work On My Browser

Does anyone has a same problem with me?

I'm using Chrome v26 and Firefox v18. Everything looks fine when I opened twitter, google, etc. Even when I opened my website (localsite) contains jquery, it looks great!

But when I opened jqueryui.com, it cant runs the demo. Buttons, menus, etc. It looks plain like no CSS or jQuery at all.

Is my browser or java lack of update? Or I just need a plugin?

Please, I need to fix this