.app_head {
  background: url("/statics/images/app/banner_xxdz.png");
  background-repeat: no-repeat;
  background-size: cover;
}

.app_ui {
  background: linear-gradient(221deg, #c2efff 0%, #60bdff 100%);
}

.app_down {
  background: url("/statics/images/app/bg_xxdz_download.png");
  background-repeat: no-repeat;
  background-size: cover;
}
.introductionOne{
  background-image: url("/statics/images/app/xxdz_bg_2.png");
  background-size: cover;
}
.introductionTwo{
  background-image: url("/statics/images/app/xxdz_bg_3.png");
  background-size: cover;

}