I bought a new mac and I've started having problems with the colour scheme. Instead of white, my apps are all grey in colour. This problem seemed to fix itself whenever I changed the screen saver to 'Drift'. Now that I've updated to the newest IOS, this doesn't work anymore. When I have apps overlapping each other, the white colour appears on the border like you can see in the picture. Can someone offer any suggestions on how to fix this problem please.