javascript 弹性菜单垂直的那种

body {cursor:hand; margin:0; padding:0; position:absolute; overflow:hidden; left:0; top:0; width:100%; height:100%;} .link {position:absolute;left:0;width:100%;height:0;background:#000;overflow:hidden;visibility:hidden;} .title {position:relative;cursor:pointer;background:#FF6600;width:100%;color:#f