.banner{position:relative;min-width:1200px;margin:0px auto;overflow:hidden;max-height:550px;}.banner .bg{width:100%;}.banner-img{position:absolute;top:0px;width:100%;height:auto;min-width:1200px;}.banner-img img{position:absolute;top:0px;left:0px;width:100%;}.banner-btn{position:absolute;bottom:16px;text-align:center;width:100%;height:10px;}.banner-btn>img{cursor:pointer;margin:0 3px;}.banner .btn{position:absolute;top:50%;margin-top:-53px;cursor:pointer;opacity:0.4;}.banner .btn:hover{opacity:1;}.banner .pre-btn{left:6%;}.banner .next-btn{right:6%;}@media (min-width: 320px) and (max-width: 479px) {.banner{min-width:320px;width:100%; height:194px;}.banner-img{min-width:320px;}.banner-btn{position:absolute;bottom:8px;text-align:center;width:100%;height:10px;}.banner-btn>img{cursor:pointer;margin:0 3px;}.banner .btn{position:absolute;top:50%;margin-top:-28px;cursor:pointer;opacity:0.4;}.banner .btn>img{width:30px;}.banner .btn:hover{opacity:1;}.banner .pre-btn{left:6%;}.banner .next-btn{right:6%;}}@media (min-width: 480px) and (max-width: 639px) {.banner{min-width:480px;width:100%; height:240px;}.banner-img{min-width:480px;}.banner-btn{position:absolute;bottom:8px;text-align:center;width:100%;height:10px;}.banner-btn>img{cursor:pointer;margin:0 3px;}.banner .btn{position:absolute;top:50%;margin-top:-28px;cursor:pointer;opacity:0.4;}.banner .btn>img{width:30px;}.banner .btn:hover{opacity:1;}.banner .pre-btn{left:6%;}.banner .next-btn{right:6%;}}