Is fashion art? On Monday night, the Met Gala red carpet answered that question. This year, the Metropolitan Museum of Art’s Costume Institute unveiled a new exhibition, “Costume Art,” pairing iconic works from the museum’s permanent collection with curated fashion garments displayed across different body forms—the naked body, the classical body, the pregnant body, the aging body, the anatomical body, and the mortal body. It’s a show built around one central idea: that the relationship between clothing, the body, and the dressed body is as worthy of serious artistic attention as anything hanging on a wall. The dress code for the night? “Fashion Is Art.” In line with the exhibition, the carpet becomes its own gallery, one where designers approach the human body the same way an artist approaches a blank canvas. Some of tonight’s guests took that literally.…