.section-courses{
    background: #f8f9fb;
    padding-top: 50px;
}
.section-courses .video-main-box{
    display: flex;
    background: #fff;
    padding: 25px 15px 30px;
    margin-bottom: 20px;
    height: 428px;
    font-size: 14px;
    color: #999;
}
.section-courses .video-main-box .left-box{
    width: 60%;
    position: relative;
}
.section-courses .video-main-box .left-box .play-box{
    position: absolute;
    top: calc(50% - 78px);
    left: calc(50% - 78px);
    width: 150px;
    height: 134px;
    background: rgba(0, 0, 0, 0.60);
    border-radius: 2px;
    text-align: center;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #fff;
}
.section-courses .video-main-box .right-box{
    width: 40%;
    padding-left: 20px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}
.section-courses .video-main-box .right-box .media-heading{
    font-size: 22px;
    color: #333;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.section-courses .video-main-box .right-box .sub-infos {
    margin: 20px 0;
    color: #666;
    font-size: 12px;
    height: 20px;
}
.section-courses .video-main-box .right-box .sub-infos ul li{
    display: inline-block;
}
.section-courses .video-main-box .right-box .sub-texts {
    line-height: 24px;
    overflow: hidden;
    padding-bottom: 25px;
}
.section-courses .video-main-box .right-box .sub-nums ul li{
    display: inline-block;
}
.video-detail-box{
    background: #fff;
    padding: 25px 15px 30px;
    margin-bottom: 80px;
}
.video-detail-box .title{
    font-size: 22px;
    color: #333;
}
.video-detail-box .video-detail-content{
    padding-top: 20px;
    min-height: 500px;
}
.video-detail-box .video-detail-content img{
    width: 100%;
}