Jquery实现无缝向上循环滚动列表的特效

 <div class="slide-title">
  <span>title1</span>
  <span>title2</span>
  <span>title3</span>
 </div>
 <div class="slide-container"><!--css设置时，注意高度是显示多少个item,如item的高度是30px，显示3个，高度则是 330 = 90px -->
  <ul class="slide-list js-slide-list">
   <li class="odd"><span>item1</span><span>item1</span><span>item1</span></li>
   <li class="even"><span>item2</span><span>item2</span><span>item2</span></li>
   <li class="even"><span>item2</span><span>item2</span><span>item2</span></li>
  </ul>
 </div>

var doscroll = function(){
 var $parent = $('.js-slide-list');
 var $first = $parent.find('li:first');
 var height = $first.height();
 $first.animate({
  height: 0 //或者改成 marginTop: -height + 'px'
  }, 500, function() {// 动画结束后，把它插到，形成无缝
  $first.css('height', height).appendTo($parent);
  // $first.css('marginTop', 0).appendTo($parent);
 });
};
setInterval(function(){doscroll()}, 2000);