Numix Green is a modern flat theme with a combination of light and dark elements. It supports Gnome, Unity, XFCE and Openbox.
Numix Green is a fork of Numix. Numix is a part of the Numix Project.
Extract the zip file to the themes directory i.e. /usr/share/themes/ or ~/.themes/.
To set the theme in Gnome, run the following commands in Terminal,
gsettings set org.gnome.desktop.interface gtk-theme "Numix Green"
gsettings set org.gnome.desktop.wm.preferences theme "Numix Green"
To set the theme in Xfce, run the following commands in Terminal,
xfconf-query -c xsettings -p /Net/ThemeName -s "Numix Green"
xfconf-query -c xfwm4 -p /general/theme -s "Numix Green"
GTK+ 3.6 or above
Murrine theme engine
Numix Green is a fork of Numix and is lisensed under GPL-3.0+.