Install Ambiance & Radiance Flat Colors GTK Theme Suite by RAVEfinity. The suite comes with variants of Ambiance Flat Theme and Radiance Flat Theme for Ubuntu Linux.
Ambiance & Radiance Flat is an modern and vivid re-imagination of the Ambiance & Radiance themes. Despite the name the theme has been completely re-designed. Featuring a clean and modern new look in your choice of 13 vibrant colors. It supports most major GTK desktops including: Cinnamon, Gnome Shell, Gnome Classic, Mate, Xfce, LXDE, Unity, OpenBox Etc.
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Install Ambiance & Radiance Flat Theme
Run the following commands in terminal to install Ambiance & Radiance Flat Colors Theme on Ubuntu Linux:
sudo add-apt-repository ppa:ravefinity-project/ppa
sudo apt-get update
sudo apt-get install ambiance-flat-colors
sudo apt-get install radiance-flat-colors
Install Theme
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Once the Theme is downloaded on the Ubuntu System, it can be used. You can also use the downloaded/installed Ubuntu Themes using Ubuntu configuration tools such as Ubuntu Tweak Tool, Unity Tweak Tool or GNOME Tweak Tool.