.down-btn a{position:absolute;z-index:1;left:50%;bottom:20px;width:24px;height:24px;margin-left:-12px;border-left:2px solid #fff;border-bottom:2px solid #fff;-webkit-transform:rotate(-45deg);transform:rotate(-45deg);-webkit-animation:sdb05 1.5s infinite;animation:sdb05 1.5s infinite;box-sizing:border-box}@-webkit-keyframes sdb05{0%{-webkit-transform:rotate(-45deg) translate(0);opacity:0}50%{opacity:1}to{-webkit-transform:rotate(-45deg) translate(-20px,20px);opacity:0}}@keyframes sdb05{0%{transform:rotate(-45deg) translate(0);opacity:0}50%{opacity:1}to{transform:rotate(-45deg) translate(-20px,20px);opacity:0}}