Hailey Bieber looked cozy in a Clara Cutout Onesie ($130) by Frankies Bikinis during a stroll in Los Angeles on Tuesday. Shortly after her viral reunion with Selena Gomez — during which she wore a chocolate-brown Saint Laurent dress with a diamond-shaped stomach cutout — Bieber gave the popular fall trend an athleisure twist.

While walking toward her car, the model looked ready for a full HIIT workout in the strappy white one-piece, which features shorts and a small stomach cutout just below the bust. From the back, the ruched design reveals a massive back-cutout detail that curves across the lower back, where Bieber had tied a rose-pink sweatshirt around her waist. She styled the look with Raf Simons Cyclon Sneakers ($465) in white, crew socks, a Femme Shoulder Bag ($3,300) by Prada, Balenciaga Oval Sunglasses, and a messy bun.

As leggings and statement scarves take their rightful places in our fall wardrobes, Bieber’s everyday ensemble is the ultimate laid-back oufit inspo. The trendy onesie, made of recycled polyester and spandex, is basically the ultimate leisure suit and can be dressed up with a fuzzy trench coat, cable-knit knee socks, and ankle boots for a day out, or it can be dressed down with a hoodie and slippers for lounging around the house.

Ahead of her get-together with Gomez, Bieber met up with Kylie Jenner to get into the Halloween spirit. With tricks and treats on the brain, the pair dressed up as Elphaba, the Wicked Witch of the West from “Wicked,” in sheer all-black ensembles and matching green body paint to grab pizza.

Shop the pieces from Bieber’s latest outfit ahead.