Tavi Gevinson thinks Seventeen magazine has a body image problem — and she is not mincing words.

Seventeen has at last, in an oblique kind of way, responded to the controversy sparked in April when a 14-year-old from Maine started an online petition calling out the magazine's over-use of Photoshop. That petition, started by a middle school student named Julia Bluhm, quickly went viral and was signed by over…

"I didn't think it was going to get this big," said a trench-coat-clad 14-year-old Julia Bluhm as she stood in the drizzle outside the Midtown skyscraper where Seventeen magazine is headquartered. Bluhm was talking about the online petition she started asking Seventeen to produce one photo spread per month without the…