Add class on scroll using jquery

Add class on scroll using jquery

function isScrolledIntoView(elem) {
  var docViewTop = $(window).scrollTop();
  var docViewBottom = docViewTop + $(window).height();

  var elemTop = $(elem).offset().top + 100;
  var elemBottom = elemTop + $(elem).height();

  return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}

$(window).on('scroll', function() {
  $("div").each(function() {
    if (isScrolledIntoView($(this))) {
      $(this).addClass("classname");
    }
  });
});