Not one for wallflowers, Alex Perry's Valentine dress comes in an acid yellow hue for instant visual impact. True to form for the silhouette-focused Australian label, the design has been crafted from flattering stretch-crêpe, sculpted into a svelve silhouette that's defined by slender double straps, a sweetheart neckline, a fitted waist and a slit-back hem. Team yours with white sandals for a high-octane party look.