Black-n-Blue-GTK is a dark GTK3 theme with blue elements.

It is based on the Back-n-Black-GTK Overhauled theme by the same author.

For detailed installation instructions please see the following tutorial created by Softpedia: http://news.softpedia.com/news/How-to-Install-GNOME-Themes-in-Ubuntu-11-10-231213.shtml