Beyoncé turned heads with her see-through Givenchy dress. But it was Rihanna who made the collective mouths of millions of social media viewers hit the floor. The star’s canary yellow Guo Pei gown — with a train as long as the red carpet — stole the show at the Met Gala in New York this week. Of course, these kinds of fashion fireworks are expected at the annual fundraiser inside the Metropolitan Museum of Art. This year’s theme, “China: Through the Looking Glass,” brought together pop singers, Hollywood royalty and Fortune 500 billionaires for a wild night of style.