.captcha{display:none;position:fixed;background-color:rgba(0,0,0,.3);top:0;left:0;height:100%;width:100%;z-index:1000}.captcha>div{position:relative;margin-top:30%;margin-left:45%;background-color:#fff;padding:10px;width:320px}.captcha button{position:relative;padding:5px;background-color:#ffe640;border:1px solid #000;margin-top:5px}