Celebrity style: 1970s inspiration Style 1970s, celebrity style, fashion Demi Lovato at the 2018 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas on May 20, 2018. (Photo by Kevin Mazur/WireImage) Kesha at the 2018 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas on May 20, 2018. (Photo by John Shearer/Getty Images for dcp Ciara at the 2018 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas on May 20, 2018. (Photo by Kevin Mazur/WireImage) Andra Day at the 90th Annual Academy Awards at the Dolby Theatre in Los Angeles on March 4, 2018. (Photo by Eric McCandless/ABC) Tiffany Haddish at the 90th Annual Academy Awards at the Dolby Theatre in Los Angeles on March 4, 2018. (Photo by Rick Rowell/ABC) Leslie Mann at the 29th Producers Guild Awards presented by Cadillac at the Beverly Hilton in Beverly Hills, California, on January 20, 2018. (Photo by John Salangsang/Invision for Producers Guild of America/AP Images)