.main_box {
    display: flex;
    flex-direction: column;
    max-width: 1200px;
    width: 100%;
    border: 1px solid #ebebeb;
}
.main_box>h1 {
    height: 50px;
    line-height: 50px;
    margin-left: 5px;
}
.video_item {
    display: flex;
    width: 100%;
    justify-content: space-between;
    height: 35px;
    line-height: 35px;
    border-top: 1px solid #ebebeb;
}
.video_item:hover {
    background-color: #ebebeb;
}
.video_zj {
    width: 100%;
    height: 35px;
    line-height: 35px;
    font-size: 1.8rem;
    font-weight: bold;
    background-color: #ebebeb;
    padding-left: 5px;
}
.video_bt {
    min-width: 300px;
    margin-left: 5px;
}
.video_sj {
    width: 120px;
}
.video_num {
    width: 80px;
    white-space: nowrap;
}
@media (max-width: 550px) {
    .video_sj {
        display: none;
    }
}