if window scroll is 0 jquery code example

Example 1: scroll to element jquery

$('html, body').animate({
  scrollTop: $("#grepperRocks").offset().top
});

Example 2: scrool to top jquerry

$("a[href='#top']").click(function() {
  $("html, body").animate({ scrollTop: 0 }, "slow");
  return false;
});