Performs a smooth page scroll to an anchor on the same page. (https://css-tricks.com/snippets/jquery/smooth-scrolling/)

Smooth Scrolling

$(function() {
  $('a[href*=#]:not([href=#])').click(function() {
    if (location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') && location.hostname == this.hostname) {
      var target = $(this.hash);
      target = target.length ? target : $('[name=' + this.hash.slice(1) +']');
      if (target.length) {
        $('html,body').animate({
          scrollTop: target.offset().top
        }, 1000);
        return false;
      }
    }
  });
});

Smooth Scrolling - Klimanov

	$(".mouse-icon").click(function() {
		$("html, body").animate({
			scrollTop : $(".s-adv").offset().top
		}, 800);
	});

А.Климанов использует фрагмент этого кода
$(".mouse-icon").click(function() {
$("html, body").animate({
scrollTop : $(".s-adv").offset().top
}, 800);
});