/* =========================
   页面标题
========================= */
.page-header {
    background: #fff;
    padding: 24px 0;
    border-bottom: 1px solid #eee;
}

.page-header h1 {
    margin: 0;
    font-size: 26px;
}

.page-header p {
    margin-top: 8px;
    color: #666;
    font-size: 14px;
}


/* =========================
   分类区域
========================= */
.filter-section {
    margin-top: 16px;
}

.category-bar {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

/* 分类按钮 */
.cat-btn {
    padding: 6px 12px;
    border: 1px solid #000;
    background: #fff;
    cursor: pointer;
    border-radius: 4px;
    font-size: 13px;
    transition: all 0.2s;
}

.cat-btn:hover {
    background: #f5f5f5;
}

.cat-btn.active {
    background: #1677ff;
    color: #fff;
    border-color: #1677ff;
}


/* =========================
   列表区域
========================= */
.list-section {
    margin-top: 20px;
}

/* 视频网格：PC 一行三个 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
    align-items: stretch;
}


/* =========================
   视频卡片
========================= */
.video-card {
    display: flex;
    flex-direction: column;
    border: 1px solid #eee;
    border-radius: 10px;
    background: #fff;
    overflow: hidden;
    transition: 0.2s;
}

.video-card:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    transform: translateY(-2px);
}


/* =========================
   视频封面
========================= */
.video-cover {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    background: #f2f5f9;
    cursor: pointer;
    overflow: hidden;
}

.video-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* 播放按钮 */
.video-play {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 46px;
    height: 46px;
    transform: translate(-50%, -50%);
    background: rgba(0,0,0,0.55);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    padding-left: 3px;
}


/* =========================
   视频内容
========================= */
.video-info {
    padding: 14px 16px 16px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.video-info h3 {
    margin: 0;
    font-size: 15px;
    line-height: 1.5;
    color: #222;
}

.video-info p {
    margin: 8px 0 0;
    font-size: 13px;
    line-height: 1.6;
    color: #666;
}


/* 元信息 */
.video-meta {
    display: flex;
    justify-content: space-between;
    gap: 10px;
    font-size: 12px;
    color: #999;
    margin-top: 10px;
}


/* 按钮 */
.video-info button {
    margin-top: auto;
    padding: 7px 12px;
    border: none;
    background: #1677ff;
    color: #fff;
    border-radius: 4px;
    cursor: pointer;
    font-size: 13px;
}

.video-info button:hover {
    background: #0958d9;
}


/* =========================
   兼容旧 file-card 写法
   如果 JS 还没完全改，也不会乱
========================= */
.file-card {
    display: flex;
    gap: 12px;
    padding: 16px;
    border: 1px solid #eee;
    border-radius: 10px;
    background: #fff;
    transition: 0.2s;
}

.file-card:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    transform: translateY(-2px);
}

.file-icon {
    width: 48px;
    height: 48px;
    background: #eaf1ff;
    color: #1677ff;
    font-weight: bold;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    flex-shrink: 0;
}

.file-info {
    flex: 1;
}

.file-info h3 {
    margin: 0;
    font-size: 15px;
}

.file-info p {
    margin: 6px 0;
    font-size: 13px;
    color: #666;
}

.file-meta {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: #999;
    margin-top: 8px;
}

.file-info button {
    margin-top: 10px;
    padding: 6px 10px;
    border: none;
    background: #1677ff;
    color: #fff;
    border-radius: 4px;
    cursor: pointer;
}


/* =========================
   空状态
========================= */
.empty {
    grid-column: 1 / -1;
    text-align: center;
    padding: 40px;
    color: #999;
    background: #fff;
    border: 1px solid #eee;
    border-radius: 10px;
}


/* =========================
   响应式：平板两列
========================= */
@media (max-width: 992px) {

    .video-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 16px;
    }

}


/* =========================
   响应式：手机一列
========================= */
@media (max-width: 768px) {

    .video-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .page-header h1 {
        font-size: 20px;
    }

    .cat-btn {
        font-size: 12px;
        padding: 5px 10px;
    }

    .video-meta,
    .file-meta {
        flex-direction: column;
        gap: 4px;
        align-items: flex-start;
    }

}