You may never have heard of Elsa Schiaparelli, one of the most important fashion designers between the two world wars, but she sure knew how to shock in her day. In the 1930s, she designed a hat shaped like a shoe, and, with surrealist artist Salvador Dali, a lobster dress. Her famous perfume, Shocking!, came packaged in her signature hot-pink shade. Though her fashion house is now lost to history — it closed in 1954 — the Italian designer, who was also Coco Chanel’s main rival, was a huge influence on fashion as we know it today. Influenced by modern art, she used whimsical touches such as colored zippers and buttons shaped like animals; made camouflage print fashionable; invented the wedge shoe and mix-and-match sportswear that was 40 years ahead of its time; and crafted the modern fashion show, with music, art and clothes-hanger-thin models. Check out the Costume Institute’s latest exhibition, “Schiaparelli and Prada: Impossible Conversations,” opening Thursday, and find out where Gaga et al. get it from.