*{margin: 0;padding: 0;list-style: none;box-sizing: border-box;}
html,body{padding:0;margin:0;min-width: 100%;min-height: 100%;font-size: 14px;background: #fff;}

.alt{width: 200px;height:30px;line-height: 30px;padding: 0 10px;text-align: center;background:rgba(0,0,0,.5);color:#fff;font-size: 12px;border-radius: 5px;position: fixed;top: 140px;left:0;right:0;bottom:0;margin:0 auto;z-index: 100;}


.mask{width: 100%;height: 100%;position: fixed;z-index: 50;top:0;left:0;background:rgba(0,0,0,.5);display: none;}
.mask-content{width:80%;height: 200px;background:#fff;z-index: 51;top:0;left:0;right:0;bottom: 0;margin: auto;border-radius: 5px;display: none;position: fixed;}


.copyright{width: 100%;position: fixed;bottom:0;left:0;text-align: center;font-size: 12px;color: #909399;padding: 10px;}
.copyright a{text-decoration: none;color: #909399;}