MLib is a set of WPF theming libraries based on MahApps.Metro, MUI, and Infragistics Themes For Microsoft Controls.
This set of theming libraries is used to power several Windows dektop app projects:
All styles are available with a Light and Dark theme.
The framework supports a dialog service that supports ContentDialogs and Modal Dialogs using one seemless API:
Review this article and give feedback on designing WPF controls for more than one specific theming library:
There is more than one NuGet package available, because not all theming features are impemented in one solid big library, but within a set of libraries. So, what you actually downlod and install depends on what you need. But most people are going to want to style an application window and its containing controls, which can be done by downloading and installing MLib with MWindowLib. Install MLib with MWindowDialogLib, if you are planning to implement ContentDialogs in your application.
The above setup with MWindowDialogLib includes the libraries for MWindowLib, so either one of the 2 deployment scenarios mentioned above, should work for most situations.
This framework is designed with Windows 10 UI guidelines in mind but it should also work for Windows 7 or 8.