.bg {
  width: 10rem;
  height: 100vh;
  background: url("../images/catBg.jpg") repeat-y;
  background-size: 100% auto;
  margin: 0 auto;
  overflow: hidden;
}
.icon-box {
  text-align: center;
  margin-top: -0.1rem;
}
.icon-box img {
  width: 5.68rem;
}
.banner-box {
  text-align: center;
}
.banner-box img {
  width: 6rem;
}
.down {
  width: 5rem;
  height: 1.17rem;
  background: url("../images/btn.png") no-repeat;
  background-size: 100% 100%;
  margin: 0 auto;
  margin-top: 0.1rem;
}