This Valentine’s Day, why not add a little color to her life? Gift your sweetheart a designer fragrance and lingerie in the same vibrant hue, from playful pink and luscious lavender to cupid’s raciest red. Dopamine shades are the hottest trend in intimate apparel. Instead of basic blacks and practical, second-skin neutrals, companies (and shoppers) are going technicolor. That means bras, panties, bodysuits, bustiers and slips in mood-enhancing brights, fun pastels or vivid jewel tones. And why