A computing system provides a graphical user interface having hierarchically-organized control galleries. The computing system displays the graphical user interface on a display device. The graphical user interface contains a document area and a control ribbon. The document area contains at least a portion of a document that a user is editing. The control ribbon includes a class control gallery. The class control gallery includes a plurality of class controls associated with different classes of related commands. The computing system displays a variation control gallery containing variation controls in a class associated with a selected one of the class controls. In response to a selection of a variation control in the variation control gallery, the computing system applies a command associated with the variation control to a document in the document area.