2 var scrollTo = function(duration) {
3 var to = document.body.scrollHeight;
4 if (duration <= 0) return;
5 var difference = to - document.body.scrollTop;
6 var perTick = difference / duration * 10;
8 var sid = setInterval(function() {
9 document.body.scrollTop = document.body.scrollTop + perTick;
10 if (document.body.scrollTop > to) {