Red may be the official color of The Devil Wears Prada 2 press tour, but when Emily Blunt showed up to the sequel's London premiere, she chose to take her manicure for the night in a direction that was slightly more springy. Blunt appeared alongside her costars at the London premiere on April 22 wearing red from head to toe. The actress wore a strapless top that flared at the waist and featured a floor-length train, and she paired it with trousers and heels in the exact same color. Her hair was styled in big, glamorous curls with a side bang , but it was her manicure that stopped me in my tracks. At the film's New York City premiere earlier this week, Blunt wore a cherry red manicure that she added a spring detail to in the form of floral-shaped pearls. This time around, though, instead of leaning all the way into the red theme, she wore a metallic glitter gradient manicure, courtesy of celebrity nail artist, Julie Kandalec .…