Get Your Ubuntu to Look like Mac OS X with a Simple Theme
Most of the themes that can pull this Mac OS X transformation work on desktop environments like GNOME, MATE, Xfce, and so on, but not all of them work in Unity. The designer of this particular version made it compatible with GTK 3.10 and it works in Ubuntu as well.
“The goal is to keep it as close as possible to ambiance on the code base with the same look as the original cupertino. If that isn’t possible for an element I will prefer the look of cupertino,” said the designer on gnome-look.org.