.ban-vd video {
    display: block;}

.ban-vd img {
    display: none;}

@media screen and (max-width: 1200px) {
    .ban-vd video {
        display: none;}
 
    .ban-vd img {
         display: block;}
/*
   .slick li:nth-child(1) {
        display: none;
   }
   .slick li:nth-child(2) {
        display: none;
   }
   */
}