Scrollbar fixed in JS

fixed-sidebar-scroll.js

self.sidebarAutoScroll = function()
  {
		window.content = $('#page>.row>div:eq(0)');
		window.sidebar = $('#page>.row>div:eq(1)');
		sidebar.data('initial-offset', sidebar.offset());
		sidebar.data('initial-height', sidebar.height());
		if (sidebar.data('initial-height')<content.height() && sidebar.data('initial-height')<$(window).height() && $(window).width()>768) {
			console.log('Using sidebarAutoScroll');
			var footerOffset = $('#footer').offset().top;
			$(window).scroll(function(e){
				if (pageYOffset>sidebar.data('initial-offset').top-20) {
					var top = Math.min(-pageYOffset-sidebar.data('initial-height')+footerOffset-40,20);
					sidebar.css({
						position:'fixed',
						top: top,
						left: window.sidebar.data('initial-offset').left-20
					});
				} else {
					sidebar.css({
						position:'static'
					});
				}
			});
		}
	};