Katy Perry set off fireworks at the Super Bowl halftime show and performed in four killer costumes by Jeremy Scott, but we couldn’t keep our eyes off of her sparkly shoes.

Perry’s longtime collaborator and celebrated costume designer Erin Lareau helped customize the glittery ankle booties, which the pop princess wanted crystallized completely — including the inside of the heel (pictured below).

“I used 12,000 tiny Swarovski crystals in clear on the tops and outsides of the heels and a Swarovski color called ‘Black Diamond Aurora Borealis’ on the inside of the heel,” Lareau exclusively tells Pret-a-Reporter. “I made sure the crystals were extremely tiny, using a blend of 3-, 5-, 7-, 9-, 10- and 12-millimeter sizes for an encrusted look, as I have learned from experience that often white can expand on camera.”

As for the booties themselves, it turns out that Perry, like Taylor Swift, opts for professional performance dance shoes for all of her live shows, and the Super Bowl was no exception. LaDuca Dance Shoes, which makes steppers for the Rockettes as well as many notable Broadway shows, created a custom 4-inch-high ankle bootie with a side zip, mitred platform and square heels, with made-in-Italy nude leather, for Perry’s performance.

Johnny Wujek, Perry’s stylist, gushed about the shoemaker: “We love Phil LaDuca — he made her heels for her California Dreams and Prismatic tours — such support and comfort. Katy loves them.” Wujek and Lareau got together at an early fitting to brainstorm on colors. “As there was no time for a shoe change, we went with clear crystals to go with all of her looks,” says Lareau. Adds Wujek: “What better than a custom crystal bootie?”

As Lareau aptly sums it up, “We can all use a little sparkle, right?” Wujek concurs: “It was her glass slipper — they were definitely the talk of the show.” We’d say so.