https://smiththerm.com/js/tabbedContent2.js

1// JavaScript Document
2
3//tab effects
4
5var TabbedContent = {
6	init: function() {	
7		$(".tab_item").mousedown(function() {
8		
9			var background = $(this).parent().find(".moving_bg");
10			
11			$(background).stop().animate({
12				left: $(this).position()['left']
13			}, {
14				duration: 300
15			});
16			
17			TabbedContent.slideContent($(this));
18			
19		});
20	},
21	
22	slideContent: function(obj) {
23		
24		var margin = $(obj).parent().parent().find(".slide_content").width();
25		margin = margin * ($(obj).prevAll().size() - 1);
26		margin = margin * -1;
27		
28		$(obj).parent().parent().find(".tabslider").stop().animate({
29			marginLeft: margin + "px"
30		}, {
31			duration: 300
32			
33		});
34	}
35}
36
37$(document).ready(function() {
38	TabbedContent.init();
39});