The practice of picking a theme and wearing it at least two ways in one outfit is far from unusual. In its most basic iteration, this method is applied to color, à la black on black. But it also carries over to materials—Kim Kardashian often wears a stretchy lycra top (albeit very fancy lycra) with an equally stretchy bottom, and looks great doing so. Trickier is the Canadian tuxedo, or Emma Stone's example, in all its mermaid-y splendor. Darker sparkle on bottom, lighter on top, a casual side slit, and a side of knowing your good colors.

—Claire Knebl

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