At the Marrakech Film Festival, we took a break from the red carpet, Dior parties, dizzying souks and sinus-clearing spice markets to visit a fashion oasis. Yves Saint Laurent said of Marrakech, “The city taught me color,” and there’s a cornea-burning amount of it at the Jardin Majorelle. An exhibit of the couturier’s vibrant djellabas, velvet Zouave pants, African bead dresses, and other Moroccan-inspired pieces—forty in all—has just launched in the shock-blue museum in the center of the sprawling garden, purchased by Saint Laurent and Pierre Bergé in 1980 and renovated ever since. On the other side of the grounds, nestled in a peaceful patch of bamboo, sits a quiet memorial to the master…