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The theme can work in any desktop environment on GTK, such as Gnome, Mate, Unity, Cinnamon and so on. If you want to get the Qt4 applications was a GTK style, run qtconfig-qt4, select GTK+ for 'Selected GUI Style' Appearance tab and will persevere.
sudo add-apt-repository ppa:noobslab/themes sudo apt-get update sudo apt-get install e17gtk-theme