.videos {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 24px;
    justify-items: center;
    padding: 10px 0 40px 0;
}

.videos video {
    width: 200px;
    height: 360px;   /* 統一影片高度 */
    object-fit: cover;   /* 保證不變形、不露白、不壓縮 */
    border-radius: 16px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    background: #000;     /* 影片載入前不會出現白框 */
}