Forget the brownstones with historic detailing that dominate Park Slope. This apartment, located at the co-op building 302 5th Avenue, is modernly renovated and downright lofty, with double-height ceilings and a raised space above the kitchen. The sleek spiral staircase also adds a contemporary touch. And with two bedrooms, 1,700 square feet over three floors, and a garden, there is plenty of room to spread out. The triplex has just hit the market for $1.5 million.