$(function() {
    var e = $("#rocket-to-top"),
    t = $(document).scrollTop(),
    n,r,i = !0;
    $(window).scroll(function() {
        var t = $(document).scrollTop();
        t == 0 ? e.css("background-position") == "0px 0px" ? e.fadeOut("slow") : i && (i = 


!1, $(".level-2").css("opacity", 1), e.delay(100).animate({
            marginTop: "-1000px"
        },
        "normal",
        function() {
            e.css({ "margin-top": "-125px",display: "none"}),i = !0})) : e.fadeIn("slow")}),
    e.hover(function() {
        $(".level-2").stop(!0).animate({opacity: 1})},
    function() {$(".level-2").stop(!0).animate({opacity: 0})}),
    //download by www.sucaijiayuan.com
    $(".level-3").click(function() {
        function t() {
            var t = e.css("background-position");
            if (e.css("display") == "none" || i == 0) {
                clearInterval(n),
                e.css("background-position", "0px 0px");
                return
                }
            switch (t){
            case "0px 0px":
                e.css("background-position", "-298px 0px");
                break;
            case "-298px 0px":
                e.css("background-position", "-447px 0px");
                break;
            case "-447px 0px":
                e.css("background-position", "-596px 0px");
                break;
            case "-596px 0px":
                e.css("background-position", "-745px 0px");
                break;
            case "-745px 0px":
                e.css("background-position", "-298px 0px");
            }
        }
        if (!i) return;
        n = setInterval(t, 50),
        $("html,body").animate({scrollTop: 0},"slow");
    });
});

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