.banner{
    width: 100%;
    height: auto;
    display: inline-block;
    margin-top: -4px;
}
.banner img{
    width: 100%;
}
.medical{
    width: 100%;
    height: auto;
    display: inline-block;
    padding: 3% 0;
}
.medical .title{
    width: 100%;
    height: auto;
    display: inline-block;
    margin-bottom: 3%;
}
.medical .title h3{
    text-align: center;
    font-size: 23px;
    text-transform: uppercase;
    font-family: Arial, Helvetica, sans-serif;
    color: #fff;
    font-weight: normal;
    display: none;
}
.medical .title h4{
    font-size: 39px;
    padding-top: 1%;
    text-align: center;
    color: rgb(115, 208, 244);
}

/* 左右分栏：左侧分类树 25% + 右侧产品 75% */
.medical-box{
    width: 100%;
    display: -webkit-flex;
    display: flex;
    align-items: flex-start;
    margin-top: 1%;
}
.nb-nav{
    width: 25%;
    flex: 0 0 25%;
    margin: 0;
    background: #f3f8f9;
    border: 1px solid #e3ecef;
    border-radius: 4px;
    overflow: hidden;
}
.nb-nav .cat-tree{
    list-style: none;
    margin: 0;
    padding: 0;
}
.nb-nav .cat-tree > li{
    border-bottom: 1px solid #e3ecef;
}
.nb-nav .cat-tree > li:last-child{
    border-bottom: none;
}
.nb-nav .cat-all a{
    display: block;
    padding: 12px 14px;
    font-size: 14px;
    line-height: 1.4;
    color: #444;
    text-decoration: none;
}
.nb-nav .cat-all.on a,
.nb-nav .cat-all a:hover{
    background: #3e6887;
    color: #fff;
    font-weight: bold;
}
.nb-nav .cat-link{
    display: block;
    padding: 12px 14px;
    font-size: 14px;
    line-height: 1.4;
    color: #444;
    text-decoration: none;
    cursor: pointer;
    position: relative;
}
.nb-nav .cat-link:hover{
    background: #e7f0f3;
    color: #3e6887;
}
.nb-nav .cat-l1.open > .cat-link,
.nb-nav .cat-l1.cur > .cat-link{
    background: #3e6887;
    color: #fff;
    font-weight: bold;
}
.nb-nav .arrow{
    float: right;
    font-size: 12px;
    transition: transform .2s ease;
}
.nb-nav .cat-l1.open > .cat-link .arrow{
    transform: rotate(90deg);
}
.nb-nav .cat-sub{
    list-style: none;
    margin: 0;
    padding: 0;
    background: #fff;
}
.nb-nav .cat-sub li a{
    display: block;
    padding: 9px 14px 9px 32px;
    font-size: 13px;
    color: #666;
    text-decoration: none;
    border-top: 1px dashed #eef3f4;
}
.nb-nav .cat-sub li a:hover{
    color: #3e6887;
    background: #f6fafb;
}
.nb-nav .cat-sub li.cur a,
.nb-nav .cat-sub li a.act,
.nb-nav .cat-l1.cur > .cat-link.act{
    color: #3e6887;
    font-weight: bold;
}
.mb-box{
    width: 75%;
    flex: 1 1 75%;
    height: auto;
    display: inline-block;
    margin-left: 3%;
    margin-top: 0;
}

.mb-box ul{
    width: 100%;
    height: auto;
    display: inline-block;
}
.mb-box li{float: left;box-sizing: border-box;border: 1px solid #eeeeee;padding: 7px;vertical-align: top;margin-bottom: 25px;margin-right: 2%;width: 23.5%;}
.mb-box li:nth-child(4n){ margin-right: 0; }
.mb-box li img{
    width: 100%;
    height: 200px;
    object-fit: cover !important;
}
.mb-box li h3{
    text-align: center;
    padding: 3% 0;
    height: 30px;
}
.mb-box li:hover{
    border: 1px solid #3e6887;
}
.mb-box li img:hover{
    width: 110%;
    transform: scale(1.1);
    -webkit-transform: scale(1.1);
    -o-transform: scale(1.1);
    -moz-transform: scale(1.1);
    filter: brightness(1);
    visibility: visible;
    -webkit-transition: all .5s;
}
.mbbb-img{
    /* height: 260px; */
    overflow: hidden;
}
@media screen and (max-width: 1024px) and (min-width: 0px) {
    .banner {
        width: 100%;
        height: auto;
        display: inline-block;
        margin-top: 12%;
    }
    .medical .title h3{
        text-align: center;
        font-size: 16px;
        text-transform: uppercase;
        font-family: Arial, Helvetica, sans-serif;
        color: #fff;
        font-weight: normal;
    }
    .medical .title h4{
        font-size: 30px;
        padding-top: 1%;
        text-align: center;
        color: rgb(115, 208, 244);
    }
    .nb-nav .cat-tree > li {
        float: none;
        width: 100%;
        margin: 0;
        padding: 0;
    }
    .nb-nav .cat-link {
        font-size: 13px;
        padding: 11px 12px;
    }
    .nb-nav .cat-sub li a {
        font-size: 12px;
    }
    .mbbb-img {
        width: 100%;
        height: auto;
        overflow: hidden;
    }
    .mb-box li {
        box-sizing: border-box;
        width: 41%;
        float: left;
        border: 1px solid #eeeeee;
        padding: 10px;
        vertical-align: top;
        margin-bottom: 15px;
        margin-right: 5px;
    }
    .mb-box li h3 {
    text-align: center;
    padding: 3% 0;
    display: -webkit-box;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 1;
    overflow: hidden;
}

    /* 窄屏：左右分栏改为上下堆叠 */
    .medical-box {
        display: block;
    }
    .nb-nav {
        width: 100%;
        flex: none;
        margin: 0 0 20px 0;
    }
    .nb-nav .cat-sub li a {
        padding-left: 28px;
    }
    .mb-box {
        width: 100%;
        flex: none;
        margin-left: 0;
    }
}