There's nothing prim and proper about Christopher Bailey's Burberry Prorsum Resort collection. Sex and sun is more like it, what with Yves Klein-blue and fuchsia neoprene cut into trenches and dresses accented with thick, black industrial zippers. Seamed knits had a whiff of the medievalism of the Fall collection, but the second-skin dresses, some ruched and shirred, showed Bailey exploring new territory.