change slider bg image

@media(max-width: 1024px) {
    .wpc-slider .et_pb_slides .et_pb_section_video {
        background-image: url("the url of the image designed for tablets in landscape mode");
    }
}
@media(max-width: 980px) {
    .wpc-slider .et_pb_slides .et_pb_section_video {
        background-image: url("the url of the image designed for tablets in portrait mode");
    }
}
@media(max-width: 767px) {
    .wpc-slider .et_pb_slides .et_pb_section_video {
        background-image: url("the url of the image designed for phones in landscape mode");
    }
}
@media(max-width: 480px) {
    .wpc-slider .et_pb_slides .et_pb_section_video {
        background-image: url("the url of the image designed for phones in portrait mode");
    }
}