On stage, millennial nostalgia is stepping into the spotlight. Across some of this year’s biggest pop tours, artists are building their wardrobes around the early 2000s, spanning everything from glitter wrap tops and micro shorts to barely-there dresses and tassels. The crystal-studded bodysuit still has its place as the definitive pop-star uniform , but it’s no longer the only option, and Y2K is proving to be one of the most fun alternatives.

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Brooklyn-based fashion designer Kelsey Randall, who created Taylor Swift’s rhinestone chainmail dress for “The Fate of Ophelia” video, is shaping this pop-girl style movement in real time. After being approached by stylist Neelo Noory, she began designing pieces for Hilary Duff’s Lucky Me tour . Duff gravitated toward the designer’s glow-in-the-dark star dress, an homage to the sticky decals we’d scatter across our ceilings, and loved that it “captured elements of [her] youth, but as a modern adult interpretation,” Randall said.…