skin.ini gradient colors

A question regarding this article:

I have no succes trying to set the gradient colors for the different (non windows) buttons in the skin.ini file.
I’d like to create a 3D-look for these buttons, I guess using gradient colors is a good start.

Could someone give me an example of a skin.ini section where these settings should be placed?
Are things like [Buttons] and [Waveforms] ‘legal’ sections within skin.ini or are they part of [Playlist] sections and so on?

Many thanks!

Gradients are only supported for the “graphic style” buttons, e.g. the buttons inside the players. Nowhere else.