Almost three years after "We Are Young" became every college student's go-to power anthem, it's good to know that fun. hasn't changed much. The Grammy-winning trio debuted their new single, "Harsh Lights," during a June 18 performance on "The Tonight Show with Jimmy Fallon." Adopting the same rollicking singalong qualities as their previous singles, the song could easily be mistaken for a cut from "Some Nights." Because, of course, it's all about late-night partiers looking for hope in the dawning light. You'll hear the line "We all got scars" repeated in abundance, and you'll know that, in the context of fun. songs, you are home.