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function createNavScrollSpy() {
	var $slider = $(".ui-scrollspy");
	function initScrollSpy() {
		var headerHeight = $('#header').outerHeight() + 70;
		var scrollTop = $(document).scrollTop() + headerHeight;
		if($slider.hasClass('initialized')) {
			return;
		}
		$slider.find('li').each(function(){
			var hash = $(this).find('a').attr("href");
			var $target = $(hash);
			if($target.length == 0) {
				$(this).remove();
				return;
			}
			if ($target.offset().top <= scrollTop + $(window).height() / 2 - $target.outerHeight() / 2) {
				$slider.find("li.active").removeClass("active");
				$(this).addClass("active");
			} else {
				$(this).removeClass("active");
			}
		});
	}
	if($slider.length) {
		initScrollSpy();
		$slider.find('a').click(function(e){
			e.preventDefault();
			$(document).off("scroll", initScrollSpy);
			$slider.find("li.active").removeClass("active");
			$(this).closest('li').addClass("active");
			var hash = $(this).attr("href");
			var target = $(hash);
			var offsetTop = target.offset().top - $(window).height() / 2 + target.outerHeight() / 2;
			$("html, body").animate({
			    scrollTop: offsetTop
				}, 500, function(){
					//window.location.hash = hash;
					$(document).on("scroll", initScrollSpy);
				}
			);
		});
		$(document).on("scroll", initScrollSpy);
	}
}