背景图片嵌入与定位

.bg-img {
  background-image: url("../img/bg.png");
  background-position: center top;
  background-repeat: no-repeat;
}
.bg01-img {
  background-image: url("../img/bg01.png");
  background-position: center top;
  background-repeat: no-repeat;
}
.bg02-img {
  background-image: url("../img/bg02.png");
  background-position: center top;
  background-repeat: no-repeat;
}
.bg03-img {
  background-image: url("../img/bg03.png");
  background-position: center top;
  background-repeat: no-repeat;
}
.bg04-img {
  background-image: url("../img/bg04.png");
  background-position: center top;
  background-repeat: no-repeat;
}