for (var i = 1; i <= 100; i++)
  
function NachOben () {
  var y = 0;
  if (window.pageYOffset) {
    y = window.pageYOffset;
  } else if (document.body && document.body.scrollTop) {
    y = document.body.scrollTop;
  }
  if (y > 0) {
    window.scrollBy(0, -10);
    setTimeout("NachOben()", 10);
  }
}