What a cool floor for a boy's room, and perfect with that bedding. I had to ask my own son what that logo is, and he told me that it's the Falcons, so the accent color would be red. You might try one large horizontal stripe across the bed wall in the gray, with a couple of smaller accent pinstripes, the most prominent of which would be red, something along these lines (see what I did there, lines?):
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