main .banner {
    position: relative;
    background: url("../img/case/typical_case_banner.png") center center no-repeat;
    background-size: cover;
    height: 600px;
}

main .banner .title {
    font-size: 48px;
    color: rgba(255, 255, 255, 1);
    text-align: center;
    padding: 240px 0 312px;
    margin: 0;
}

main .banner .bannerNav {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(21, 28, 42, 0.5);
    list-style: none;
    display: flex;
    align-items: center;
    font-size: 14px;
    margin: 0;
    height: 52px;
    padding: 0;
}

main .banner .bannerNav .item {
    color: #ffffff;
    text-decoration: none;
    display: block;
    padding: 17px 15px;
}
main .banner .bannerNav .item:first-child{
    margin-left:  375px; 
}
main .banner .bannerNav .item:hover,
main .banner .bannerNav .item.active {
    background: rgba(17, 144, 255, 0.5);

}

main .content {
    line-height: 2;
    width: 1210px;
    margin: 97px auto 66px;
    list-style: none;
    padding: 0;
}

main .content li .title {
    font-size: 24px;
    color: rgba(50, 58, 64, 1);
    margin-bottom: 30px;
    text-align: center;
}

main .content li p:not(.title) {
    text-indent: 2em;
    color: #707980;
    font-size: 16px;
    margin: 0;
}