.keyvisual--common-01 {
    background-image: url(/m/cmn_files/img/corporate/disclosure/keyvisual.jpg);
}

@media screen and (max-width: 768px) {
    .keyvisual--common-01 {
        background-image: url(/m/cmn_files/img/corporate/disclosure/keyvisual-sp.jpg);
    }
}