I'm so grumpy with myself and I don't even know how it happened - I'll blame my kids - but I just noticed a small ding in the metal on the front edge of the lid right where you put your fingers to open it. It's slightly rough when I run my finger over it. I know this is on me, but does anybody have any suggestions for smoothing it out? My Air is gold, so I can't just go to town with sandpaper. Managed to keep my 2012 Pro in perfect cosmetic shape for almost a decade, and I did this a week in to ownership!