Meghan Markle took a dark step away from royal customs with her outfit detail during an outing

On Monday, a pregnant Duchess Meghan made a surprise appearance at the British Fashion Awards at Royal Albert Hall in London. She was there to present a special award to one of her favorite designers.

Fans noticed that there was one particular detail in Meghan’s look that seemed to stray from the normal Royal etiquette.

Duchess Meghan, 37, was at the British Fashion Awards to honor her wedding dress designer, Clare Waight Keller. The fashion designer is the artistic director of Givenchy and Meghan’s wedding dress creator.

The Duchess, alongside actress Rosamund Pike, presented Keller with the British Womenswear Designer of the Year Award. For the occasion, the Royal intentionally wore a one-shoulder Givenchy black dress.

For more on this story go to our Twitter account @amomama_usa. Meghan completed her look with a gold "Karat" heel by Tamara Mellon and a gold cuff bracelet by Pippa Small.

She revealed to the audience:

“It is such an honor to be here celebrating British fashion and British fashion designers in my new home of the U.K.”

However, one thing about her look that stood out was her visible black nail polish. The Duchess broke Royal style protocol by straying away from the translucent nail shades that were previously set by the Queen and Duchess Kate.

It’s clear that she was color coordinating her nails with her black dress and the look worked well. Despite it not being an official rule, it is widely known that the Queen finds colorful nail polish distracting.

Brighter colors aren’t banned for Royals; however, the Queen does prefer nude colors for official engagements. The Queen’s favorite brand is Essie’s “Ballet Slippers.”

The monarch has been using the bottles of the sheer, pale pink polish since 1989. At the time, her hairdresser had written to the founder Essie Weingarten and described the nail polish as “the only color Her Majesty would wear.”

Meghan was in her element at the awards ceremony. After her surprise appearance, she let her guard down by taking part in a photo booth session with Keller and Pike.

The three posed for a candid photo booth image that showed the duchess cradling her growing baby bump.