Fashion designer Stella McCartney is marking the 10-year anniversary of her sportswear collaboration with Adidas by launching something new with the brand: Stellasport, a funky fresh line of athletic apparel, footwear and accessories aimed at teens and young women. “The adidas Stellasport girl is young, current and vibrant, looking to make a statement and stand out. We wanted to bring that to life within the collection and fuse performance with style to create performance pop,” McCartney says. Retailing for an affordable $20 to $100 (prices for Adidas by Stella McCartney, by comparison, can go up to $460) , the collection launches on Jan. 15. To wit, the collection includes eye-catching tanks, tees, tights and sports bras featuring Adidas’ Climalite technology in popping prints and bright colors.