JQuery Back to top - Scroll to top

JQuery Back to top - Scroll to top code

<script>
$(document).ready(function(){
 // hide #back-top first
 $("#back-top").hide(); 
 // fade in #back-top
 $(function () {
  $(window).scroll(function () {
   if ($(this).scrollTop() > 100) {
    $('#back-top').fadeIn();
   } else {
    $('#back-top').fadeOut();
   }
  });
  // scroll body to 0px on click
  $('#back-top a').click(function () {
   $('body,html').animate({
    scrollTop: 0
   }, 800);
   return false;
  });
 });
});
</script>