Thank you for contacting Telerik Support.
What you are describing can be achieved with Sitefinity.
Sitefinity uses the following structure for the front end presentations. You have pages to which you can add widgets to display content. Those pages are either based on templates, which you define or use built in ones, or you create pages which are not based on any templates. In the templates you can define content areas which can be populated from the pages inheriting those templates, or you can put common content (Navigation, footer cotnent, etc.) which is available on all pages inheriting from those templates. The visual appearance of the templates is defined by the themes. Those themes include CSS rules, and images for them. So you can create different templates and themes for different areas of interest.
For example you can create the following - create one base page template where you want to add all common content for all pages and define layout and content ares. Then for each area of interest you can create a template which inherits from the base one and has different theme creating different appearance for pages using this template. If you make a change in the base template those changes will the passed down to the child templates and to the pages using them.
the Telerik team