To set or change the default group theme (affecting all groups in your community you haven't individually customized):
- Log in as an administrator or as the owner of the group.
- Navigate to the group home page.
- Mouse over Management.
- Click Control Panel.
- Navigate to System administration > Group administration > Configuration > Default group theme.
- In the Default Theme drop-down list, select an available theme to use for all groups.
- Click Save.