.banner img{
    display: block;
    width: 100%;}
.banner{
    position: relative;
        height: 450px;
            width: 1900px;}
.banner .swiper-slide a{
    display: block;
    position: relative;}

.banner .btn{
    width: 40px;
    height: 57px;
    background: transparent no-repeat 50%/100%;}
.banner .prev{
    left: 170px;
    background-image: url(images/prev.png);}
.banner .next{
    right: 170px;
    background-image: url(images/next.png);}