EXCLUSIVE AT NET-A-PORTER. ROTATE Birger Christensen's Jeanette Friis Madsen and Thora Valdimars lovingly create the kind of dresses they’ve always dreamt of owning. Referencing '80s prom styles, this 'Petra' mini is cut from rigid floral-jacquard and lightly pleated for shape. It has a close fit through the bodice and ruched cap sleeves that can be worn on or off the shoulders. Match your heels and jewelry to the pops of silver.