1. A computer-implemented method for rendering one or more graphical hierarchical diagrams for display by a display device, the method comprising: receiving selection of a first graphic definition for rendering a first graphical hierarchical diagram, the first graphic definition specifying a first graphical element; in response to the selection of the first graphic definition, rendering the first graphical element within the first graphical hierarchical diagram in a drawing pane on the display device; receiving content text within the first graphical element; receiving a first customization to a presentation property of the first graphical element; updating the presentation property of the first graphical element with the first customization; receiving a second customization to a semantic property of the first graphical element; updating the semantic property of the first graphical element with the second customization; receiving a selection of a second graphic definition; and in response to the selection of the second graphic definition, rendering a second graphical hierarchical diagram comprising a second graphical element that includes the content text and the updated semantic property but not the updated presentation property.