body {
    background: #F6F5F6;
}

.lab_box {
    position: relative;
}

.lab_head {
    height: 279px;
    background: #00AED3;
    width: 100%;
}

.lab_content {
    width: 1200px;
    margin: -279px auto 0;
    padding-bottom: 117px;
}

.lab_title {
    font-size: 44px;
    font-weight: 600;
    color: #FFFFFF;
    padding: 44px 0 47px;
    text-align: center;
}

.exper_list {
    background-color: #fff;
    padding: 0 10px;
    margin: 17px 0 14px;
}

.exper_item {
    font-size: 16px;
    font-weight: 600;
    color: #000000;
    height: 57px;
    line-height: 57px;
    padding: 0 28px;
}

    .exper_item.active {
        color: #00C1DE;
    }

.video_item {
    width: 282px;
    height: 230px;
    padding: 9px 0;
    background: #fff;
    box-shadow: 0px 2px 4px 0px rgba(110, 110, 110, 0.5);
    margin-right: 24px;
    margin-bottom: 24px;
    display:block;
}

    .video_item:nth-child(4n) {
        margin-right: 0;
    }

.video_text {
    padding: 12px;
    height: 44px;
    font-weight: 600;
    color: #000000;
    line-height: 22px;
    overflow: hidden;
    text-overflow: ellipsis;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    word-break: break-all;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
}

.video_head {
    width: 266px;
    height: 169px;
    position: relative;
    margin: 0 auto;
}

.video_bg {
    width: 266px;
    height: 169px;
    display: block;
    object-fit: cover;
}

.video_icon {
    width: 57px;
    height: 57px;
    display: block;
    position: absolute;
    left: 17px;
    bottom: 12px;
}

.video_btn {
    width: 1200px;
    height: 41px;
    background: #DEDCDC;
    text-align: center;
    line-height: 41px;
    font-size: 18px;
    font-weight: 600;
    color: #4B4B4B;
    margin-top: 25px;
    display: block;
}
    .video_btn:hover{
        cursor:pointer
    }
    .video_list {
        margin-top: 40px;
    }
.head_banner_bg{
    width:100%;
    height:100%
}