ScrollObserver callbacks

Triggers functions at specific points during scroll.
ScrollObservers callbacks functions are defined directly in the onScroll() parameters Object.

animate('.square', {
  x: 100,
  autoplay: onScroll({
    container: '.container',
    target: '.section',
    axis: 'y',
    enter: 'bottom top',
    leave: 'top bottom',
    sync: true,
┌──────────────────────────┐
│   onEnter: () => {},     │
│   onLeave: () => {},     ├─ Callbacks
│   onUpdate: () => {},    │
└──────────────────────────┘
  })
});