Facebook has lost it's color

Hello,
the colour has gone out of my internet screen, I have been playing with the display settings on my computer and I have stuffed something up. when I go onto facebook all the blue on the top of the screen has disappeared and I can't see the tab buttons. Whatever I have done it has also done something to my Word program half of it has changed back to the old grey style and other half is still the same, (blue version 2007)