@media (min-width: 320px) {
  .myimg {
    height:100%!important;
  }
}
@media (min-width: 520px) {
  .myimg {
    height:100%!important;
  }
}
@media (min-width: 640px) {
  .myimg {
    height:100%!important;
  }
}
@media (min-width: 768px) {
  .myimg {
    height:100%!important;
  }
}
@media (min-width: 992px) {
  .myimg {
    height:5100px!important;
  }
}
@media (min-width: 1200px) {
  .myimg {
    height:610px!important;
  }
}