Arc is a flat theme with transparent elements for GTK+4, GTK+ 3, GTK+ 2 and GNOME Shell which supports GTK+ 3 and GTK+ 2 based desktop environments like GNOME, Unity, Budgie, Pantheon, Xfce, MATE, Cinnamon, etc. Arc also includes a GTK+ theme for Plank.

Arc is available in four variants: Arc, Arc-Darker, Arc-Dark, Arc-Lighter