Motion

M3 Expressive's springs as --md-sys-motion-spatial-* and --md-sys-motion-effects-*, each with its own duration. Reduced motion makes all of them instant.

Position, size and shape move on the spatial springs, which overshoot — fast for small elements, slow for large ones. Colour and opacity move on the effects springs, which never overshoot. Always pair an easing with its duration; everything that moves goes through these tokens, so reduced motion makes it instant. The Standard scheme (motion.scheme) swaps the spatial springs for a restrained set.