*{padding:0;margin:0}#main{width:100%;max-width:640px;overflow-x:hidden;overflow-y:scroll;margin:0 auto}.alert-toast{position:fixed;z-index:99999;max-width:600px;padding:8px 16px;background:rgba(0,0,0,0.7);border-radius:4px;top:33%;left:50%;transform:translate(-50%,-50%);-webkit-transform:translate(-50%,-50%);color:#fff}