/* 自定义额外样式 */
#toc-nav a {
    display: block;
    padding: 0.25rem 0;
    color: #64748b;
    transition: color 0.2s;
}
#toc-nav a:hover {
    color: #2563eb;
}
#toc-nav a.active {
    color: #2563eb;
    font-weight: 500;
}