You know, I just tried and can't reproduce in Chrome either. I'm able to reproduce in Safari, and now having successfully nerd-sniped myself I'm pretty confident it's actually a bug in Safari. The `@media screen and (min-width: 60em)` doesn't update its definition of an `em` when the page is zoomed in or out, so zooming the page gives more pixels for the "min-width" part, but the "60em" is still being treated as the original zoom level.