Here is a guide to install the Ambiance Adium Message Style for Empathy.
If you don’t like the default message box theme from Empathy you should give the Ambiance Adium message style a try. It’s my favourite theme and i have been using it for some years. Installing the theme doesn’t take long and isn’t difficult at all.
To install the theme you first need to make the adium and the message-styles folders in your .local/share folder. To do this open a terminal window (press Ctrl+Alt+T)and copy+paste the following line:
mkdir .local/share/adium/ && mkdir .local/share/adium/message-styles/
To download, extract and move the Ambiance Adium theme to the folders you just made copy+paste the following lines:
cd ~/Downloads/
wget http://gnome-look.org/CONTENT/content-files/146855-Ambiance.AdiumMessageStyle-1.8.tar.gz
tar -xzvf 146855-Ambiance.AdiumMessageStyle-1.8.tar.gz
mv Ambiance.AdiumMessageStyle/ ~/.local/share/adium/message-styles/
When done you can close the terminal window and to use the Ambiance Adium message style click on the Dash Home button and search for: empathy. In the Empathy menu click on Edit -> Preferences and select the Themes tab. Click on the Chat Theme button and select Ambiance. There are some variants available under the Variant button. Click on it and select them to get a preview of the variant and select the variant you like.