paper-gtk-theme : Paper is a modern GTK3 desktop theme suite ( http://snwh.org/paper/ )
paper-icon-theme : Paper is simple and modern icon theme inspired by Google's material design guidelines. ( http://snwh.org/paper/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a qwin-overlay
For Paludis use this rsync : rsync://gentoo.zugaina.org/qwin-overlay-portage
If you have a problem : ycarus(-at-)zugaina.org