Hi, at first thanks a lot for your answer.

Can you give me a hint how I can make the documents execute my css style and not only to display the code?
Because I'm not sure where I should start trying and maybe you've got a suggestion.

Regards
Jan

I would write it as a custom application. There are 40+ applications in Phabricator which can provide you examples. We don't provide support for building custom applications, so you're on your own and should expect it to task a few days (if you're familiar with Phabricator development). This isn't really a good task if you're new to Phabricator. If you need us to write such an application, we do have Consulting available.