text: $(function() {
      var $topLink = $('.top-link');
      var $topLinks = $('.top-links');
      var $itembg = $('.itembg');
      var bgleft = $itembg[0].offsetLeft,
          bgtop = $itembg[0].offsetTop;
  
      $topLink.mouseover(function() {
          $itembg.stop()
          $itembg.animate({
              left: this.offsetLeft,
              top: this.offsetTop
          }, 300)
      })
      $topLinks.mouseleave(function() {
              $itembg.animate({
                  left: bgleft,
                  top: bgtop
              }, 300)
          })
          // 顶部导航滑动件事
      function _scroll() {
          var scrollTop = $(window).scrollTop();
          if (scrollTop < 10) {
              $('.position-fixed').css('opacity', 1);
          } else {
              $('.position-fixed').css({
                  opacity: 0.6
              });
          }
      }
      $(window).on('scroll', function() {
          _scroll()
      });
  })