滑入（向下滚动）框

Question

向下滑动时，新的内容模块会滑动到位。但它不起作用：/我认为scss存在问题......是否需要？没有它有没有解决方案？嗯...

以下是我的演示：FIDDLE DEMO

(function($) {

  /**
  * Copyright 2012, Digital Fusion
  * Licensed under the MIT license.
  * http://teamdf.com/jquery-plugins/license/
  *
  * @author Sam Sehnert
  * @desc A small plugin that checks whether elements are within
  *     the user visible viewport of a web browser.
  *     only accounts for vertical position, not horizontal.
  */

  $.fn.visible = function(partial) {

  var $t            = $(this),
      $w            = $(window),
      viewTop       = $w.scrollTop(),
      viewBottom    = viewTop + $w.height(),
      _top          = $t.offset().top,
      _bottom       = _top + $t.height(),
      compareTop    = partial === true ? _bottom : _top,
      compareBottom = partial === true ? _top : _bottom;

return ((compareBottom <= viewBottom) && (compareTop >= viewTop));

};

})(jQuery);

var win = $(window);

var allMods = $(".module");

allMods.each(function(i, el) {
var el = $(el);
if (el.visible(true)) {
el.addClass("already-visible"); 
} 
});

win.scroll(function(event) {

allMods.each(function(i, el) {
var el = $(el);
if (el.visible(true)) {
  el.addClass("come-in"); 
} 
});

});