#wachat a{position:fixed;z-index:9999;right:0;float:right;top:40%;margin-top:-25px;cursor:pointer;min-width:50px;max-width:150px;color:#fff;text-align:center;padding:10px;margin:0 auto 0 auto;background:#20b038;-webkit-transition:All .5s ease;-moz-transition:All .5s ease;-o-transition:All .5s ease;-ms-transition:All .5s ease;transition:All .5s ease}#wachat a img{width:50px}