.main_nav {
    border-color: #162665;
}

.main_nav a.on {
    border-color: #162665;
    color: #162665;
    background: url(../images/icon-view.png) no-repeat 90% center;
}
.page_content {
    display: flex;
    margin-top: 10px;
    min-height: 500px;
    margin-bottom: 60px;
}

.page_main_content {
    flex: 1;
    width: 100%;
    padding-left: 70px;
    flex-direction: column;
}

.service_group,
.service_list {
    display: flex;
    flex-direction: column;
}

.service_group {
    margin: 0 0 25px;
}

.sg_title {
    border-bottom: 1px solid #ddd;
    font-size: 18px;
    color: #162665;
    font-weight: bold;
    margin: 0 0 15px;
}

.sg_title span {
    display: inline-block;
    padding-bottom: 10px;
    border-bottom: 4px solid #162665;
}

.sg_items {
    display: flex;
    flex-wrap: wrap;
}

.sg_item {
    position: relative;
    border: 1px solid #ddd;
    padding: 10px;
    margin-right: 15px;
    margin-bottom: 15px;
    width: calc((100% - 30px) / 3);
}

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

.sg_item:hover {
    color: #162665;
    border: 1px solid #162665;
}

.ellipsis {
    white-space: nowrap; /* 禁止换行 */
    overflow: hidden; /* 隐藏超出内容 */
    text-overflow: ellipsis; /* 显示省略号 */
}

.full_cover_link {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 99;
}

@media only screen and (max-width: 750px) {
    .page_content {
        min-height: 300px;
        margin-bottom: 20px;
    }
    .page_main_content {
        flex: 1;
        padding-left: 0;
        flex-direction: column;
    }

    .main_nav {
        min-height: 80px;
    }

    .main_nav a.on {
        border-color: #162665;
        color: #162665;
        background: url(../images/icon-view.png) no-repeat right center;
    }

    .sg_item {
        width: calc((100% - 15px) / 2);
    }

    .sg_item:nth-child(3n) {
        margin-right: 15px;
    }

    .sg_item:nth-child(2n) {
        margin-right: 0;
    }
}