.cover {
  background-size: cover !important;
}
.contain {
  background-size: contain !important;
}

@media screen and (min-width: 30em) {
  .cover-ns {
    background-size: cover !important;
  }
  .contain-ns {
    background-size: contain !important;
  }
}

@media screen and (min-width: 30em) and (max-width: 60em) {
  .cover-m {
    background-size: cover !important;
  }
  .contain-m {
    background-size: contain !important;
  }
}

@media screen and (max-width: 60em) and (orientation: landscape) {
  .cover-ml {
    background-size: cover !important;
  }
  .contain-ml {
    background-size: contain !important;
  }
}

@media screen and (min-width: 60em) {
  .cover-l {
    background-size: cover !important;
  }
  .contain-l {
    background-size: contain !important;
  }
}