#app {
  background: #ffffff;
  overflow: hidden;
}
.content1 {
  width: 100%;
  position: relative;
  margin-bottom: 29px;
}
.content1-bg {
  width: 100%;
  height: auto;
  z-index: -1;
}
.btns {
  position: absolute;
  top: 48%;
  left: 18.65%;
  z-index: 1;
  width: 100%;
}
.btn {
  width: 10%;
  height: auto;
}
.btn1 {
  margin-right: 1.6%;
}
.content2 {
  margin-bottom: 40px;
  margin-left: 18.1%
}
.content2-bg {
  width: 60.4%;
  height: auto
}
.content3-bg {
  width: 81.25%;
  height: auto;
  float: right;
}
.content4 {
  margin-top: -150px;
}
.content4-bg {
  width: 79.17%;
  height: auto;
}