In this tutorial we will help you render the top panel of the Gnome Shell transparent using the Gimp and some terminal commands. The default color for the Gnome shell panel is solid black and to make it transparent we need to use an image manipulation program like the Gimp. You can also use any other color, but try to choose only what fits with your panel's font.
If you haven't installed the Gimp on Ubuntu 11.10, you can do with this command:
sudo apt-get install gimp
Then open the terminal and edit the panel-border.svg image file with this command:
sudo gimp /usr/share/gnome-shell/theme/panel-border.svg
Under the "Layers" section, move the opacity slider to the left to make your image transparent. For full transparency, move the slider to zero. For my part, I will adjust it to 20.
Save now your file and rename it as panel-border.png since Gimp doesn't support svg files.
Edit now the gnome-shell.css file with this command:
Search and replace:
Save your file and exit. Log out the current session and log back in. Your Gnome Shell panel is now transparent.