getScrollTop.js

function getScrollTopPosition(){
  return document.documentElement.scrollTop || document.body.scrollTop || document.body.scrollTop || window.pageYOffset || 0;
}

// because it's so fucking difficult to detect the scrolling element, just move them all
function moveToScrollTop(amount) {
  document.documentElement.scrollTop = amount;
  document.body.parentNode.scrollTop = amount;
  document.body.scrollTop = amount;
}