Gigi Hadid turned 24 on Monday (22 April) and celebrated by throwing a private birthday party for her famous friends and family in New York. But rather than a formal affair, the model opted for a decidedly low-key dress code: denim. The theme was reportedly inspired by Britney Spears' and Justin Timberlake's famous double denim outing at the American Music Awards in 2001.
A reminder:

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The result was pleasingly casual; instead of the guests arriving in their finery, it made a refreshing change to see the A-list guestlist in more low-key attire. The birthday girl herself kept it simple in jeans and a denim jacket with a crop top, Dr Martens and layered necklaces (so far, so '90s), while sister Bella Hadid went for a triple denim look, pairing her jeans with a denim corset and loose-fit shirt.

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Ashley Graham accessorised a belted denim jacket with thigh-high boots, while Martha Hunt kept it straightforward in skinny jeans and a tank top.

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Gotham//Getty Images
Model Olivia Culpo added a high-octane twist to her denim look with glittering boots and a statement necklace, while Yolanda Hadid arrived wearing a tailored three-piece denim suit.

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Gotham//Getty Images
Helena Christensen paired her high-waisted jeans with a lacy bustier top, while Hailee Steinfeld opted for a denim-trimmed tweed outfit.

Gotham//Getty Images

Gotham//Getty Images
There was, however, one high-profile guest who notably decided to skip the dress code. Taylor Swift turned up at the New York party wearing that Mango blazer (which is now in the sale) over a floral Zimmermann dress, with Rupert Sanderson sandals and an Anya Hindmarch cat-print bag.

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