Once a hard-edged Modernist penthouse, the home is now an airy retreat. Kendall Wilkinson gave the abode’s light-filled rooms and meticulous craftsmanship a jolt with clean, modern furniture and graphic designs. The palette was simple: black, white, anthracite, and charcoal. A checkered marble floor sets the stage for a sofa in dark green velvet and chrome-plate Italian chairs. Views of San Francisco abound through curtain-less windows. Custom crystal chandeliers and sconces add shimmer and elegance throughout.