[Plugin: Stout Google Calendar] change color of agenda background

in working with the color settings for a calendar in agenda view, I cannot seem to change the light blue background. Your screenshot shows the ability to do this, but none of the settings seems to make that change. Also some settings seem to do nothing when changed.

How did you get the brown and cream colors to appear as shown in the screen shot?

http://wordpress.org/extend/plugins/stout-google-calendar/