For all the transparent, glossy, 3-D bezel-laden GTK themes out there, there are also sublime simplistic ones too.
White in particular makes for a minimalistic and elegant choice. As such below are my pick of some of the best minimalistic and more refined themes out there, designed to give your system that touch of class.
Flat BSM
Flat BSM is a clean, clear and refined theme designed to stay out of your way in order to just let you get on with using your computer. It comes in 7 different colours, but you can also easily choose your own colour scheme as the theme is totally customizable! Way to go!
You do need the clearlooks engine installed ” which most Ubuntu users will already have by default.
What sells this theme for me is it’s gorgeous panels. A lot of GTK themes totally neglect the panel, but Flat BSM makes it just as gorgeous as the rest of the theme, forgoing the usual semi-transparent look for a sleek glossy background that truly just pops the cherry on top of this theme.