How can you change the GTK Theme and Window Decorations separately in Unity?

I'm trying to mix and match a GTK theme with a different Window Decoration, but I cant see where this can be done. The Unity-Tweak-Tool changes the two in tandem, but this is not necessarily what I want.

You can try to change the Window theme and the GTK theme separately using the gsettings command, Ubuntu Tweak or gnome-tweak-tool.

Gsettings

There are two schemas, for the gtk theme is org.gnome.desktop.interface & for the window theme is org.gnome.desktop.wm.preferences.

In this example I will set the gtk-theme to Ambiance and the Window-theme to Radiance.

1) Open a Terminal window Ctrl+Alt+T and type:

• gsettings set org.gnome.desktop.interface gtk-theme Ambiance
• gsettings set org.gnome.desktop.wm.preferences theme Radiance

The result in Nautilus:

Ubuntu-Tweak

To install ubuntu-tweak you can add this ppa.

1) Open a Terminal window Ctrl+Alt+T and type:

• sudo add-apt-repository ppa:tualatrix/ppa
• sudo apt-get update
• sudo apt-get install ubuntu-tweak

2) Open the Ubuntu-Tweak and go to Tweaks -> Theme.

Gnome-Tweak-Tool

To install the gnome-tweak-tool

1) Open a Terminal window Ctrl+Alt+T and type:

• sudo apt-get install gnome-tweak-tool

2) Open the gnome-tweak-tool application and go to Theme.

NOTE: In this application the window-theme is named as Current Theme.

Hope this helps.