This song was produced and co-written by the pop/electronica duo Dreamlab, who comprise Leah Haywood (vocals, keyboards) and Daniel James (vocals, guitars). The other co-writer was the Swedish singer-songwriter Tony Nilsson.
Selena told Billboard magazine: "It was actually the first song I recorded and it was really fun and I feel like everyone can relate to that song. It's kind of one of those songs about living in the moment while keeping it a big huge summer dance track. That one was really fun and kind of dance poppy."
The video finds Selena partying and dancing her life away. She explained the meaning of both the song and the clip is having fun, and throwing caution to the wind. "The song 'Hit the Lights' is that missed opportunity," she said. "The dreams that you wish you would go for and basically the song is just encouraging people to [let] loose and have fun and be young and crazy. This video is more organic than anything I've done before. It's about being with people you love and enjoying the moment and embracing the moment you're in your life."
"Lean On" was originally sent by Major Lazer to both Rihanna and Nicki Minaj's camps as a slower reggae track. After both parties rejected the tune, Major Lazer recruited Danish singer MØ to supply vocals and recorded it themselves.