This term specify the type of encryption used in commercially produced DVD-Video discs. CSS stands for Content Scramble System, and its primary purpose is to prevent copies of DVDs.
It means that there is a CSS code needed in order to access that area. And, I think in order to get the CSS code, you would have to go to the mod of the site.
CSS is a copy protection method used on DVDs. It was released around 1996 and is longer protective - workarounds have been found. Nonetheless, working around DRM protection, or any copy protection, is against the law.
CSS stands for Content Scrambling System. This is a type of data encryption used on certain media. It was created as a means to prevent direct copying of files.