You can see how it’s done in DevTools; within the style-block in head (under: <– Art Direction Styles –> ). It’s a very nifty
css-animation on the background-position of a (zero height?) background-image within a zero height element with a large amount of
padding-bottom in percentages. (Title itself is an image too).
BTW, try the
background-size property for the faking of animations on gradients: