It was all about metallic for ?on last night’s . The singer dazzled in a bronze-hued Lanvin top,?Vivienne Westwood burgundy bubble hem skirt, matching Brian Atwood heels, and edgy gold Jennifer Fisher jewelry. Lopez?went with a?shiny lip and dark-rimmed eyes to complement her ensemble, and opted for slicked-back simple waves when it came to her hair. The judge’s nails also stuck to the metallic theme, and were?done in a shimmery combination of colors. “I liked the way the material of the top and skirt picked up the light and shimmered, and decided to make a similar color on Jen’s nails,” nail expert?Tom Bachik tells InStyle.com exclusively. “I wanted to create depth and dimension so I started by painting her nails black and then put a mix of glitters on top. I used two golds and a bronze to create that dimension among the tricolor. Finally, we cleaned off on the edges so there was a black edge all around.” Want more J. Lo fashion? Tune in every Thursday and Friday this season to catch more of Jennifer Lopez??s?American Idol?style moments right here on InStyle.com, and?!