“That sweater is not just blue, it’s not turquoise, it’s not lapis, it’s actually cerulean.” Two decades later, Miranda Priestly’s disdainful monologue in  The Devil Wears Prada  continues to be the best example of how style travels from runway to retail store and becomes a pop-culture shorthand at affordable prices. In the film, Meryl Streep’s character tells her assistant how designer Oscar de la Renta’s 2002 collection of cerulean gowns was reinterpreted by Yves Saint Laurent through cerulean military jackets, was adapted by eight different designers before it filtered down to the department store. All these years later, the process may be the same. But the journey is dramatically faster. How soon does what you see on a Paris or Milan runway end up on racks at Indian malls? “A dress can make its way from the runway to a fast-fashion retailer in as little as two to three weeks,” says designer Samant Chauhan.…