@media screen and (max-width: 576px) {
  #ms-slide-0 .ms-slide-bgcont {
    background-image: url(https://iie.smu.edu.sg/sites/iie.smu.edu.sg/files/banner-image/Build_Test_and_Launch_within_the_Train_Network.jpg);
    background-size: cover;
    background-position: center;
  }
  #ms-slide-0 .ms-slide-bgcont img {visibility: hidden}
  
}