.mod {
    text-align: center;
    position: relative;
}

.mod-s1 {
    background: url(../../images/sale/818/2020/pc/00-banner.jpg) no-repeat center top;
    height: 1037px;
}

.mod-s1 a {
    width: 300px;
    height: 80px;
    position: absolute;
    z-index: 2;
    top: 545px;
    margin: 0 auto 0 -150px;
}

.mod-s2 {
    background: url(../../images/sale/818/2020/pc/01-img.jpg) no-repeat center top;
    height: 480px;
}

.mod-s2 a {
    width: 300px;
    height: 80px;
    position: absolute;
    z-index: 2;
    top: 325px;
    margin: 0 auto 0 -454px;
}

.mod-s3 {
    background: url(../../images/sale/818/2020/pc/02-img.jpg) no-repeat center top;
    height: 520px;
}

.mod-s3 a {
    width: 300px;
    height: 80px;
    position: absolute;
    z-index: 2;
    top: 325px;
    margin: 0 auto 0 -454px;
}

.mod-s4 {
    background: url(../../images/sale/818/2020/pc/03-img.jpg) no-repeat center top;
    height: 678px;
}

.mod-s4 a {
    width: 300px;
    height: 80px;
    position: absolute;
    z-index: 2;
    top: 395px;
    margin: 0 auto 0 70px;
}

@media screen and (max-width: 768px) {
    .mob {
        display: flex;
        position: relative;
    }

    .mob img {
        width: 100%;
    }

    .mob-s2 a {
        position: absolute;
        width: 40%;
        height: 4rem;
        left: 5%;
        top: 66%;
    }

    .mob-s3 a {
        position: absolute;
        width: 40%;
        height: 4rem;
        left: 5%;
        top: 66%;
    }

    .mob-s4 a {
        position: absolute;
        width: 40%;
        height: 4rem;
        top: 66%;
        right: 3%;
    }
}