Mediterranean is dark theme series, it is designed for users who like dark themes. This series has 11 different variants and available for GTK 3 + 2, it is currently pre-release 2.0 version. In this series all the themes are same but with different color variants and some bitmaps.
1st: zonColor Wallpapers used in screenshots, Also checkout Black Wallpapers
2nd: zonColor-Icons used in screenshots, Also checkout icons collection
3rd: You can use Gnome-tweak-tool or Ubuntu-Tweak to change icons and themes.
To install Mediterranean themes in Ubuntu/Linux Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal: