.banner {
  width: 0;
  height: 500px;
  display: block;
  margin: 0 auto;
  position: relative;
}
.banner .swiper-container {
  width: 1920px;
  height: 500px;
  display: block;
  overflow: hidden;
  position: absolute;
  left: 50%;
  top: 0;
  margin-left: -960px;
  background: #eee;
}
.banner .swiper-button-prev {
  left: 50%;
  margin-left: -590px;
}
.banner .swiper-button-next {
  right: 50%;
  margin-right: -590px;
}