* {
  padding: 0;
  margin: 0;
}

.container {
  position: absolute;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: url(bg.jpg);
  background-attachment: fixed;
  background-size: cover;
}

.box {
  position: absolute;
  background: url(bg.jpg);
  background-attachment: fixed;
  background-size: cover;
}