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Hey Ryzippy, Google really doesn't want to penalize site owners for making web design decisions without taking their crawler into account, so I don't think there will be a problem. That said, I'd recommend that you upload the new design to a test group first, just in case. This is not a risk-free solution, though, so I'd also recommend that you push back on your web developer. Is there really no way to use the same H1 for both the mobile and desktop design? This is exactly what responsive design is for, to use the same HTML elements, but different CSS based on the screen width. Anyway, good luck, and check back in here to let other SEOs know if using multiple H1s will cause a problem! Best, Kristina