As the fashion world mourned the loss of Oscar de la Renta yesterday, Jennifer Lawrence stepped out in a sartorial tribute to the legend at the Elle Women in Hollywood event in LA. Clad in a long-sleeved, white lace mini dress by the late designer's label, J-Law was a perfect vision of the de la Renta woman: elegant, classic and timelessly romantic. Five stars, lady. Five. Stars. Here are other red (well, gray, technically) carpet highlights from the evening, from Bella Thorne's yellow leather Gucci frock to mega jumpsuit steez from Emmy Rossum and Chiara Ferragni…