Hello, sunshine!

Occasionally, the fashion world rallies behind some silly rules. (No white after Labor Day, never mix black and brown, you know the drill.) But thanks to Margot Robbie, we can finally put the "blondes shouldn't wear yellow" decree to rest.

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The Wolf of Wall Street beauty, 24, shined bright on the Harper's Bazaar Women of the Year Awards red carpet in London on Nov. 4, thanks to her plunging lemon confection of a dress. Robbie chose the Rosie Assoulin floor-sweeper for the occasion, pairing the sunny design with rose gold sandals and bold jewels.

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Most importantly, the Pan Am alum didn't hide her golden tresses! Instead, Robbie wore her blonde locks smooth and long, and looked gorgeous doing so, proving once and for all that anyone—including blondes—can wear yellow.