Zone properties make it easy to apply unique styling to specific iParts, for emphasis and contrast.
To apply a style to an iPart’s zone property, edit the content record, click Properties, and enter the name of the class in Zone CSS Class:

All tree-name themes contain three zone style classes:
■ TitleBarNoBorder – simply removes the bottom border from iPart headers
■ CCOGrayBg – applies a gray background to content appearing in CCO tabs

■ CalloutBlockType1 – accentuates an iPart whose border is enabled
Aspen:
Birch: