.is_pc{
    display: block;
}
.is_sp{
    display: none;
}
.cp_banner img{
    position: relative;
    z-index: 50;
}

@media screen and (max-width: 750px) {
    .is_pc{
        display: none;
    }
    .is_sp{
        display: block;
    }
}

.cp_banner img{
    max-width: 960px;
    width: 100%;
    height: auto;
    margin: calc( 60px + 25px) auto -90px;
}
@media screen and (max-width: 750px) {
    .cp_banner img{
        padding: 20px;
        margin: calc( 40px + 25px) auto -50px;
    }
}