prefers-reduced-motion ignored

A consequence worth stating: motion is never the sole signal, for the same reason colour is not (C-20). Honouring the reduced-motion path removes the animation, so any state that was communicated by movement alone is communicated to that user by nothing at all. A field that only shakes on a bad password has no error state under reduced motion. Pair the motion with text, an icon, or a colour change that survives without it.