Overriding properties within a custom user control

I'm sure this is more simple than I'm making it, but all I'm trying to do is assign background and foreground properties to a control that is embedded within a custom control by assigning the background and/or foreground of the custom control.

For example, the custom control consists of nothing more than a grid with a textbox and a button. The button accesses a device which returns a value, which in turn puts the value in the textbox.

If I set the foreground and background color of the custom control, I want those values to apply to the textbox ONLY!

Notice how it's filling the entire background of the custom control.

Thanks all.....