Regardless of the theme/style a user prefers, the theme you designate will be displayed instead whenever they go to specific pages. Force Style Plus extends this functionality in XenForo to include more pages.
Force the style for notable members pages
Choose which notable members pages the style is forced on
Force the style for the help page section
Choose which help pages the style is forced on
Force the style on XenForo Resource Manager
Force the style for Siropu Chat rooms
Choose which chat rooms the style is forced on