If you are the portal administrator, you are responsible for selecting a style to serve as the system default.
When a style is deleted, all pages and regions that used the style revert to the page group default style, or the system default style if there is no page group default style.
To
set the system default style, you must be the portal administrator.
In the Services portlet, click Global Settings.
Note: By default, the Services portlet is on the Administer tab of the Builder page.
In the Default Style section, choose a style from the Display Name list.
Note: The list includes all public styles in the Shared Objects page group.
Click OK.
Creating a style
Choosing a default style for a page group
Applying a style to a page
Applying a style to a region