Today, we will see two nice themes that were already ported to GTK 3.6 and are compatible with Ubuntu 12.10 or Linux Mint 14. The first theme is MediterraneanDark and the second is FlatStudioDark which will be enjoyed by fans of dark themes. You can use them with Unity or Gnome Shell.
MediterraneanDark
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FlatStudioDark
In this tutorial, we will help you install them via PPA, you can add it with these commands:
sudo add-apt-repository ppa:upubuntu-com/gtk+3.6
sudo apt-get update
To install MediterraneanDark, enter this command:
sudo apt-get install mediterranean-dark-gtk
For FlatStudioDark, run this command:
sudo apt-get install flatstudiodark-gtk
Use Gnome Tweak Tool to enable the two themes.
MediterraneanDark/FlatStudioDark Removal
If you want to remove these themes, enter these commands:
sudo apt-get remove flatstudiodark-gtk
sudo apt-get remove mediterranean-dark-gtk
sudo add-apt-repository --remove ppa:upubuntu-com/gtk+3.6
sudo apt-get update