How to change theme colors?
Solution 1:
A useful tool to customize gtk theme is gtk-theme-config.
You can see here the greybird gtk theme wich has a blue scheme by default turned to purple and the gtk theme config at the bottom right corner.
Greybird gtk them wich has a blue scheme by default.
For install it in Saucy 13.10 and Trusty 14.04:
sudo apt install gtk-theme-config
For previous ubuntu releases:
sudo add-apt-repository ppa:shimmerproject/ppa
sudo apt update
sudo apt install gtk-theme-config
Source: http://www.webupd8.org/2012/09/customize-gtk3-gtk2-theme-colors-using.html
Important
Notice this will not work with the new default themes in ubuntu as explained here: http://www.webupd8.org/2014/04/ambiance-and-radiance-colors-theme-pack.html
Solution 2:
If all you need is more green, just install one of the themes available at ubuntu-art.org:
Solution 3:
The simplest way is maybe to install the color-varied versions of Radiance and Ambiance: Ambiance & Radiance Colors.
sudo add-apt-repository ppa:ravefinity-project/ppa
sudo apt-get update
sudo apt-get install ambiance-colors radiance-colors
And then change the theme with Unity Tweak Tool.
sudo apt install unity-tweak-tool
As for the icons, we can change only the color if we want, while keeping the same theme (in fact creating a color-variation version of the default) with:
sudo apt remove folder-color folder-color-caja folder-color-common
sudo add-apt-repository ppa:costales/folder-color
sudo apt update
sudo apt install folder-color folder-color-caja