.mv{position:relative;background:none}.mv__bg{position:absolute;top:0;left:0;width:100%;height:520px}.mv__bg ul.slider{width:100%;height:520px}.mv__bg ul.slider li{width:100%;height:520px;background-position:center center;background-repeat:no-repeat;background-size:cover}@media only screen and (max-width: 769px){.mv__bg{height:154.4vw}.mv__bg ul.slider{height:154.4vw}.mv__bg ul.slider li{height:154.4vw;background-position:center center;background-repeat:no-repeat;background-size:cover}}