How to fade background image in GUIStyle in and out?

Hi,

I'd like to fade all GUI elements in and out over time. From other threads I know how to fade in and out Textures of a DrawTexture command (set GUI.color beforehand). But is it possible to change the alpha of a background image of a GUIStyle (used by the GUI element), too? I only know, how to change the text color alpha of a GUIStyle...

GUI.color affects all GUI drawn. You can set it before you draw a window and then again before you draw the window's content.