Prefers-reduced-motion update

[Joe Snell]

Per this comment on twitter:
https://twitter.com/scottjehl/status/1086287082031583232?s=11

.. we should change the style to be the following (more stable / reliable):
`@media (prefers-reduced-motion: reduce) {

*,
*::before,
*::after {
	animation-duration: 0.1s !important;
            transition-duration: 0.1s !important;
}

}`

[Joe Snell]

Branch for issue updated / merged