text: $(function($) {
      function scrollToPos() {
          var title = "回到顶部";
          $('<a href="#" id="to-top" title="' + title + '"> <div class="to-top-wrap"></div></a>').appendTo("body");
          var $e = $('#to-top')
          $(window).scroll(function() {
              $(window).scrollTop() > $(window).height() ? $e.fadeIn(500) : $e.fadeOut(500)
          })
          $e.click(function(event) {
              event.preventDefault();
              $("html,body").animate({
                  scrollTop: 0
              }, 600)
          })
      }
      scrollToPos();
  })
  