Panel And Slingshot Transparency

Open Files as Administrator.

Enter your password....

Navigate to the folder /usr/share/themes/elementary/gtk-3.0/

Find the file apps.css and open it ( scratch-text-editor ).

Scroll down to the following section :

Just below is the line : background-color: alpha (#000, 0.7);

#000 is the color ( see : http://www.color-hex.com/ ), 0.7 is the transparency.

Change the number 0.7 into a lower number ( e.g. 0.3 ).

To see the change type in a terminal :

killall wingpanel


In order to make the slingshot-launcher and the drop down menus from the panel transparent, we need to change another file :

cd /usr/share/themes/elementary/gtk-3.0/
sudo nano granite-widgets.css

Type Ctrl+W ( Where Is ) and type popover_bg and hit Enter.

There are three lines containing alpha and we need to change the last numbers ( 0.97 ) in them ( make them lower ). So it will look like this :

Type Ctrl+O ( WriteOut ), hit Enter and Ctrl+X

To see the changes :
killall wingpanel
killall slingshot-launcher