https://centerlevko.ru/wp-content/themes/levko/js/jquery.accordion.source.js

1(function(jQuery){
2     jQuery.fn.extend({  
3         accordion: function() {
4            return this.each(function() {
5
6            	var $ul = $(this);
7            	
8				if($ul.data('accordiated'))
9					return false;
10													
11				$.each($ul.find('ul, li>div'), function(){
12					$(this).data('accordiated', true);
13					$(this).hide();
14				});
15				$.each($ul.find('a'), function(){
16					$(this).click(function(e){
17						activate(this);
18						return void(0);
19					});
20				});
21				
22				var active = (location.hash)?$(this).find('a[href=' + location.hash + ']')[0]:'';
23
24				if(active){
25					activate(active, 'toggle');
26					$(active).parents().show();
27				}
28				if ($(".accordion li").hasClass("active")){
29					$(".accordion li.active").parents('ul').not(".accordion").show();
30					$(".accordion li.active").parents('li').addClass("active");
31
32					var elem = $(".accordion ul li, .accordion>li").has("ul");
33					elem.children('a').addClass("used");
34					elem.children('a').click(function(){
35					 return false;
36					});
37				}
38				function activate(el,effect){
39					$(el).parent('li').toggleClass('active').siblings().removeClass('active').children('ul, div').slideUp('fast');
40					$(el).siblings('ul, div')[(effect || 'slideToggle')]((!effect)?'fast':null);
41				}
42				
43            });
44        } 
45    }); 
46})(jQuery);