顶部下拉在线客服代码可以实现顶部展开及收回效果，特别适合对特效情有独钟、以及网站无空闲区域放置客服，又想凸显客服的朋友使用。-Online customer service at the top of the drop-down at the top of the code may be implemented to expand and recover the results, especially suitable for the soft spot effects, as well as