        background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 12px; padding: 1rem;
    }
    .toc-title { font-weight: 700; margin: 0 0 0.5rem 0; font-size: 0.95rem; color: #334155; }
    .toc-list { list-style: none; margin: 0; padding: 0; }
    .toc-list li { margin: 0.25rem 0; }
    .toc-link { color: #64748b; text-decoration: none; font-size: 0.9rem; }
    .toc-link.active { color: #4f46e5; font-weight: 600; }
    
    .article-content h2 {
        color: var(--primary-color);
        margin-to