After combining two apartments, a new full-floor residence serves as a backdrop to the clients’ art collection. From the foyer, an extended gallery displaying paintings runs alongside the double-height living room, den, and airy dining room. The black-and-white color scheme emphasizes the interior’s clean, modern lines, with built-in cabinetry minimizing clutter and pocket doors seamlessly connecting the generously scaled rooms. The risers on the floating staircase were re-stained a deep ebony to make an artful statement of their own.