.develop-top {
    position: relative;
}

.develop-top>img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.develop-top:after {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, .4);
}

.develop-txt {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 76%;
    z-index: 3;
    transform: translate(-50%, -50%);
}

.develop-ico {
    height: 120px;
    text-align: center;
}

.develop-ico img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.develop-tit {
    color: #fff;
    text-align: center;
    line-height: 1.2;
}

.develop-des {
    text-align: center;
    line-height: 1.875;
    color: #fff;
    margin-top: 18px;
}

.develop-btm {
    display: flex;
    flex-wrap: wrap;
}

.develop-bitem {
    flex: 0 0 30.55%;
    margin-right: 4.175%;
}

.develop-bitem:nth-child(3n) {
    margin-right: 0;
}

@media screen and (max-width:1600px) {
    .develop-ico {
        height: 100px;
    }
}

@media screen and (max-width:1200px) {
    .develop-ico {
        height: 80px;
    }
}

@media screen and (max-width:768px) {
    .develop-ico {
        height: 60px;
    }

    .develop-bitem {
        flex: 0 0 100%;
        margin-right: 0;
        margin-bottom: 5vw;
    }

    .develop-top {
        height: 300px;
    }

    .develop-txt {
        width: 90%;
    }

    .develop-des {
        line-height: 1.5;
    }
}