.page-header {
    padding: 4rem 0;
    text-align: center;
    background: var(--container-bg-color);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
}
.page-header__title {
    font-size: var(--h1-font-size);
    margin-bottom: 1rem;
}
.page-header__nav {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 2rem;
}
.content-section {
    padding-top: 5rem; /* 增加顶部内边距以避免被固定导航栏遮挡 */
}
 .video-list {
    list-style-type: none; /* 不显示列表标记 */
    padding-left: 2rem;      /* 左边距 */
}
.video-list li {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}
.video-list a {
    font-weight: 600;
}
.video-list a:hover {
    text-decoration: underline;
}