You get a white window with black text on the top. (techradar.com)
I've found that an off - white / light grey with black text works best and is easy on the eyes, but your mileage may, of course, vary. (4thletter.net)
The flight number is indicated in black text in the lower left corner in case you need to write this down when calling a different airline to book this award. (travelcodex.com)