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/*ScrollUp button controller (self init)*/
    (function(){
        function ScrollTop(tmpl) {
            this._tmpl = tmpl || '<div id="scrollUp"><i class="upButton"></i></div>';
            this._isActive = false;
            
            this.init();
        }
        ScrollTop.prototype.init = function () {
            this._$btn = $(this._tmpl);
            $('body').append(this._$btn);
            
            this.scrollBtnToggler();
            
            this._$btn.on('click', this.scrollTop.bind(this));
            $(window).on('scroll', this.scrollBtnToggler.bind(this));
        };
        ScrollTop.prototype.scrollBtnToggler = function () {
            if ( $(document).scrollTop() > $(window).height() && !this._isActive ) {
                this._$btn.fadeIn({queue : false, duration: 400})
                    .animate({'bottom' : '40px'}, 400);
                this._isActive = true;
            } else if ( $(document).scrollTop() < $(window).height() && this._isActive ) {
                this._$btn.fadeOut({queue : false, duration: 400})
                    .animate({'bottom' : '-20px'}, 400);
                this._isActive = false;
            }
        };
        ScrollTop.prototype.scrollTop = function(){
            $("html, body").animate({scrollTop: 0}, 500);
            return false;
        };
        
        var scrollTopBtn = new ScrollTop();
    })();