Styling information should be documented for the content and page editors (like g.d.o group organizers )

Problem/Motivation

One can apply limited styling on panels used in groups.drupal.org as seen in the attached image.
The problem is, as mentioned at about d.o, "in order to preserve Drupal.org's 'brand' identity, Bluecheese is not available outside of the Drupal.org implementers team," and g.d.o group organizers cannot decide which classes are available for block items. (Create custom page layouts for your Group seems to have some obsolete information and a few open documents like CSS Guide for the Blue Cheese theme implementers does not help much either.)

Proposed resolution

1. Bluecheese maintainers should document the styling information including the list of css classes which can be applied to block items, for the content and page editors. Such a document would be helpful also for other uses like common images, preferred content styling etc.
2. As soon as such a document becomes available the above mentioned g.d.o wiki page can be updated accordingly.