Install arc-theme by entering the following commands in the terminal:
sudo apt update sudo apt install arc-theme
Description:
Flat theme with transparent elements
Arc is a flat theme with transparent elements for GTK+ 3, GTK+ 2 and GNOME Shell which supports GTK+ 3 and GTK+ 2 based desktop environments like GNOME, Unity, Budgie, Pantheon, Xfce, MATE, etc. Arc also includes a GTK+ theme for Plank. . Arc is available in three variants: Arc, Arc-Darker, Arc-Dark
Homepage: https://github.com/nicohood/arc-theme
Version: 20180114-1ubuntu1
Section: universe/misc