Could you recommend anything to put on this in order to make it all black again? I guess my foot probably grazed it and I've tried to to clean it, but I'm not having any luck. Thank you!!!!http://img142.imageshack.us/i/leftcardoor.jpg/I suppose you would call this a "scuff."I also tried Mothers Back-to-Black, which got some of it out, but it still needs some work.