Passcode lock not the same colours as background?
A couple of months ago my iPhone 4's passcode lock colours changed to a light grey, even though my background colours were blue, orange, and light blue. Even the category colours changed to a browny-purple type colour. I've changed my background numerous times to see whether or not it was just a glitch, but it's still the same colour. I'm on the latest software update so, everything is updated. It makes the background of my homescreen and lockscreen look disgusting, is there any way to change it?
EDIT: I found out what to do, I have no idea how it changed on it's own.
iPhone 4, iOS 7.1