Vertex is a theme for GTK 3, GTK 2, Gnome-Shell and Cinnamon.
It supports GTK 3 and GTK 2 based desktop environments like Gnome,
Cinnamon, Mate, XFCE, Budgie, Pantheon, etc.
Themes for Chrome/Chromium and Firefox browser are included, too.
The theme comes with three variants to choose from: the default
variant with dark header-bars, a light variant, and a dark variant.