.body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.banner {
    width: 100%;
    height: 63vw;
    background: url('../images/banner4_2025_cn_m.jpg?20200814a') center 0/100% 100% no-repeat;
}

.main_box {
    width: 100%;
    height: fit-content;
}

.main_box_content {
    width: 100%;
    height: fit-content;
}

.sub_box {
    width: 100%;
    height: fit-content;
    padding: 0 19px;
    box-sizing: border-box;
    margin-bottom: 40px;
}

.sub_box_title {
    font-size: 18px;
    font-family: Source Han Sans CN Bold, Source Han Sans CN Bold-Bold;
    font-weight: 700;
    text-align: left;
    color: #3478dd;
    line-height: 18px;
    margin: 12px 0;
}

.sub_box_title:before {
    content: '';
    display: inline-flex;
    width: 18px;
    height: 18px;
    background: url('../images/qa_icon_1.png?20200814') left 0/18px 18px no-repeat;
    padding-right: 15px;
    vertical-align: middle;
}

.sub_box_content {
    width: 100%;
    height: fit-content;
}

.sub_box_item {
    width: fit-content;
    height: fit-content;
    margin: 15px 0;
}

.sub_box_item_question {
    font-size: 15px;
    font-family: Source Han Sans CN Regular, Source Han Sans CN Regular-Regular;
    font-weight: 400;
    text-align: left;
    color: #333333;
    line-height: 25px;
    margin: 6px 0;
}

.sub_box_item_question:before {
    content: '';
    display: inline-flex;
    width: 14px;
    height: 14px;
    background: url('../images/qa_icon_2.png?20200814') left 0/14px 14px no-repeat;
    padding-right: 8px;
    vertical-align: middle;
}

.sub_box_item_answer {
    font-size: 15px;
    font-family: Source Han Sans CN Regular, Source Han Sans CN Regular-Regular;
    font-weight: 400;
    text-align: left;
    color: #000000;
    line-height: 25px;
}

.sub_box_item_answer:before {
    content: 'A:';
    font-size: 15px;
    font-family: Source Han Sans CN Regular, Source Han Sans CN Regular-Regular;
    font-weight: 400;
    text-align: left;
    color: #000000;
    line-height: 25px;
}

.footer {
    background-color: #f8f8f8;
    min-height: 109px;
    height: fit-content;
    width: 100%;
    font-size: 7px;
    color: #999999;
    text-align: center;
    padding: 42px 10px 10px 10px;
    box-sizing: border-box;
}

.nav_block {
    position: relative;
    width: 100%;
    height: 47px;
    background-color: #F8F8F8;
}

#nav_box_holder {
    position: relative;
    width: 100%;
    height: 47px;
}

#nav_box {
    position: absolute;
    left: 0;
    top: 0;
    display: flex;
    align-items: center;
    width: 100%;
    height: 47px;
    background-color: #F8F8F8;
    z-index: 2;
}

.nav_box_item {
    flex-shrink: 0;
    flex-grow: 1;
    text-align: center;
    border-right: solid 1px #d8d8d8;
    box-sizing: border-box;
    font-size: 15px;
    font-family: Microsoft YaHei Regular, Microsoft YaHei Regular-Regular;
    font-weight: 400;
    text-align: center;
    color: #999999;
    line-height: 16px;
    padding: 10px 0;
}

.nav_box_item-selected {
    color: #3478dd !important;
}