"We wanted something young, something that felt fresh, so we looked to surfing and skating, the things we grew up on," Lazaro Hernandez said backstage after Wednesday's fun, energetic Proenza Schouler show. Any of that sound familiar? Hernandez and his partner, Jack McCollough, started playing with tie-dyes and scuba elements for Resort. Here, they pushed the idea: They took the notion of track jackets wrapped around waists and built those elements right into tank dresses and shirtdresses, and they teamed a pair of color-blocked track pants with a great tailored jacket for a sporty-chic effect. It's the sort of nonchalant look a lot of designers struggle to pull off; these guys nailed it effortlessly.

As for those tie-dyes? There was nothing hippie about them, cut as they were into micro-mini racerback tanks or shifts and trimmed at the hem with thick layers of plastic fringe. For evening, the silhouette was short, short, short. A few of the cocktail numbers featured the bra-cup bodices the duo has made their signature, mixed here with tiers of micro ruffles. Other dresses floated away from the body in dense embroideries of beads and feathers, and still others featured the brightest, most novel animal prints to hit a runway in recent memory. Each look was perched on wedge-heel woven sandals as colorful as the clothes, and a few of the models had blue or purple streaks in their hair. There have been moments in the last couple of seasons where the boys—at 28, they still qualify for the term—were straining a bit too hard to come off as "grown-up" designers. For Spring, they found a groove with a concept so simple it should've been more obvious: designing for the cool girls they like to hang out with.