Francisco Costa made a gorgeous contribution to Calvin Klein’s house message of sexy, urban, rock ’n’ roll cool with his fall collection. Luxurious skins that flaunted technical details formed the core of the look, giving it richness and depth, while likely pricing many of pieces out of production. There were two lengths: mini and maxi. The first took the form of shifts that were Mod-ish because shifts always are, but also modern because of Costa’s nuanced cuts. He managed to make a keyhole neckline seductive, exaggerating the cutout to circle the entire breastbone. The latter came on coats and slinky ribbed knits that have staged a revival this season. A pair of long, lean black styles — a jumpsuit and tank dress with elongated leather yokes — did the house proud and brought the look back to the body.