We've got quite a few requests to post some dark GTK3 themes, so here it is: DeLorean Dark and MediterraneanNight are two great dark GTK3 themes that support both GTK 3.6 (Ubuntu 12.10) and 3.4 (Ubuntu 12.04).
DeLorean Dark is a beautiful GTK3 theme that supports the latest GTK 3.6. There's also a GTK2 theme available, which has been completely redesigned recently.
Also, the theme isn't just for GNOME (this includes Unity, Cinnamon, etc.), there are Xfce and Openbox themes available as well.
Here are some DeLorean Dark screenshots:
To install DeLorean Dark in Ubuntu 12.10, use the following commands:
sudo add-apt-repository ppa:killhellokitty/themes.ppa sudo apt-get update sudo apt-get install delorean-dark-theme-3.6
The theme is also available for GTK 3.4 / Ubuntu 12.04. To install it in Ubuntu 12.04, instead of the last command above, use:
sudo apt-get install delorean-dark
For other Linux distributions and some extras which include Firefox, Thunderbird or Chromium themes, tweaks and fixes, see the DeLorean Dark DeviantArt page: for GTK 3.6 | for GTK 3.4.
MediterraneanNight is a pack of 3 darkish GTK3 themes that's available for both GTK 3.4 and 3.6: MediterraneanDark, MediterraneanLight and MediterraneanNight as well as for Xfce.
The theme is a variation of Adwaita Cupertino (now called Gnome Cupertino) with dark colors, which not only looks very nice, but it's also relaxing for the eyes.
Here are a few Mediterranean* screenshots:
The theme is highly customizable, but it requires editing some theme files. To make it easier for the users, I've uploaded MediterraneanNight to the WebUpd8 Themes PPA along with a script I've created that lets you customize the theme: you can select the environment used: GNOME Shell / Cinnamon or Unity, the style used by Nautilus, the Unity panel, tabs style, choose between regular and glossy window buttons and more:
Note that the Nautilus 3.4 styles seem to also work with Nautilus 3.6.
To install the MediterraneanNight theme pack in Ubuntu 13.04, 12.10 (GTK 3.6) or 12.04 (GTK 3.4), use the following commands:
sudo add-apt-repository ppa:webupd8team/themes sudo apt-get update sudo apt-get install mediterraneannight-gtk-theme
Then, if you want to configure the theme using the script I've created, run:
Or, you can manually edit the theme yourself - see the readme inside each Mediterranean theme folder under /usr/share/themes/
For other Linux distributions, download MediterraneanNight via Gnome-Look (available for both GTK 3.4 and 3.6).