.banner {
    background-image: url('../../images/成功案例.png');
}
.Case-content {
    flex-wrap: wrap;
    margin-bottom: 190px;
}
.Case-content .card {
    margin-top: 50px;
    margin-right: 50px;
    width: calc(100%/3 - 34px);
}
.Case-content .card:nth-child(3),
.Case-content .card:nth-child(6) {
    margin-right: 0;
}
.item-content {
    padding-bottom: 30px;
}