You'll be surprised how flexible and scalable system is with the following functionality:
- Themes - allows you to create your own or change default one to match your website UI;
- Modules - as system is modular, you can built any module on your own or customize existing ones to expand functionality and integrate any feature you are interested in;
- Localization - you can add your own language and translate interface with built-in interface. A big advantage is that you can change naming of any word or expression if you have specifics in your company or business.
Also, you have SingularCore open-source engine at your disposal to change anything inside if you need more complicated modifications.