Meghan is proving it’s one of those old sartorial “rules” that stands to be disproved

Meghan Markle Just Proved This Controversial Fashion Rule Was Meant to Be Broken

Meghan Markle has perfected the art of wearing black and navy together.

While it was once considered a fashion no-no, Meghan is proving it’s one of those old sartorial “rules” that stands to be disproved.

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The Duchess of Sussex looked chic in a navy belted top with ruffled details by Oscar de la Renta and black flared pants by Altuzarra for a sporty outing with Prince Harry on Monday.

Between outings with the Queen and royal walkabouts, Meghan is learning the ups and downs of life as the Duchess of Sussex.

Image zoom Meghan Markle Chris Jackson/Getty

Although she has quickly adapted to many of the minutiae of royal dos and don’ts, she “has found certain rules in the royal household difficult to understand, like the fact that the Queen prefers women in dresses or skirts rather than trouser suits, and is often asking Harry why things have to be done in a certain way,” a source previously told PEOPLE.

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“I think she finds it a little frustrating at times, but this is her new life, and she has to deal with it,” the source added.

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She has also taken fashion cues from her sister-in-law, Kate Middleton, by opting for pantyhose instead of her usual bare legs and smaller clutches instead of larger handbags.