* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        :root {
            --primary-color: #0066cc;
            --text-dark: #1a1a1a;
            --text-gray: #666;
            --border-color: #e0e0e0;
            --bg-light: #f8f9fa;
            --white: #ffffff;
        }

        body {
            font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
            line-height: 1.6;
            color: var(--text-dark);
            background: var(--white);
        }

        /* Header */
        header {
            background: var(--white);
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
        }

        nav {
            max-width: 1200px;
            margin: 0 auto;
            padding: 1rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.75rem;
            font-weight: 700;
            color: var(--text-dark);
            text-decoration: none;
        }

        .nav-links {
            display: flex;
            gap: 2rem;
            list-style: none;
        }

        .nav-links a {
            color: var(--text-dark);
            text-decoration: none;
            font-weight: 500;
            transition: color 0.3s;
        }

        .nav-links a:hover,
        .nav-links a.active {
            color: var(--primary-color);
        }

        /* Main Container */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 2rem;
            display: grid;
            grid-template-columns: 1fr 350px;
            gap: 3rem;
        }

        /* Loading Spinner */
        .loading {
            text-align: center;
            padding: 4rem 2rem;
            font-size: 1.2rem;
            color: var(--text-gray);
        }

        .spinner {
            border: 4px solid var(--border-color);
            border-top: 4px solid var(--primary-color);
            border-radius: 50%;
            width: 50px;
            height: 50px;
            animation: spin 1s linear infinite;
            margin: 0 auto 1rem;
        }

        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }

        /* Breadcrumb */
        .breadcrumb {
            display: flex;
            gap: 0.5rem;
            margin-bottom: 2rem;
            font-size: 0.9rem;
            color: var(--text-gray);
            flex-wrap: wrap;
        }

        .breadcrumb a {
            color: var(--primary-color);
            text-decoration: none;
        }

        .breadcrumb a:hover {
            text-decoration: underline;
        }

        /* Article */
        article {
            background: var(--white);
        }

        .article-header {
            margin-bottom: 2rem;
        }

        .article-category {
            color: var(--primary-color);
            font-weight: 600;
            font-size: 0.9rem;
            text-transform: uppercase;
            text-decoration: none;
            margin-bottom: 0.5rem;
            display: inline-block;
        }

        .article-title {
            font-size: 2.25rem;
            font-weight: 700;
            line-height: 1.3;
            margin-bottom: 1rem;
            color: var(--text-dark);
        }

        .article-meta {
            display: flex;
            gap: 0.5rem;
            color: var(--text-gray);
            font-size: 0.9rem;
        }

        .article-meta a {
            color: var(--primary-color);
            text-decoration: none;
        }

        .article-content {
            font-size: 1.05rem;
            line-height: 1.8;
            color: #333;
        }

        .article-content p {
            margin-bottom: 1.5rem;
        }

        .article-content img {
            width: 100%;
            max-width: 700px;
            height: auto;
            margin: 2rem auto;
            display: block;
            border-radius: 4px;
        }

        .article-content h2 {
            font-size: 1.75rem;
            font-weight: 700;
            margin: 2.5rem 0 1.5rem;
            color: var(--text-dark);
        }

        .article-content h3 {
            font-size: 1.4rem;
            font-weight: 600;
            margin: 2rem 0 1rem;
            color: var(--text-dark);
        }

        /* Table of Contents */
        .toc {
            background: var(--bg-light);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 1.5rem;
            margin: 2rem 0;
        }

        .toc-title {
            font-size: 1.25rem;
            font-weight: 600;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .toc-list {
            list-style: none;
        }

        .toc-list li {
            margin-bottom: 0.75rem;
        }

        .toc-list a {
            color: var(--text-dark);
            text-decoration: none;
            display: flex;
            align-items: flex-start;
            gap: 0.5rem;
        }

        .toc-list a:hover {
            color: var(--primary-color);
        }

        .toc-number {
            font-weight: 600;
            min-width: 1.5rem;
        }

        /* Sidebar */
        aside {
            position: sticky;
            top: 100px;
            height: fit-content;
        }

        .sidebar-section {
            background: var(--white);
            margin-bottom: 2rem;
        }

        .sidebar-title {
            font-size: 1.5rem;
            font-weight: 700;
            margin-bottom: 1.5rem;
            color: var(--text-dark);
        }

        .post-card {
            display: flex;
            gap: 1rem;
            margin-bottom: 1.5rem;
            padding-bottom: 1.5rem;
            border-bottom: 1px solid var(--border-color);
        }

        .post-card:last-child {
            border-bottom: none;
            margin-bottom: 0;
            padding-bottom: 0;
        }

        .post-thumbnail {
            width: 80px;
            height: 80px;
            object-fit: cover;
            border-radius: 4px;
            flex-shrink: 0;
        }

        .post-info {
            flex: 1;
        }

        .post-title {
            font-size: 0.95rem;
            font-weight: 600;
            line-height: 1.4;
            margin-bottom: 0;
        }

        .post-title a {
            color: var(--text-dark);
            text-decoration: none;
        }

        .post-title a:hover {
            color: var(--primary-color);
        }

        /* Categories */
        .categories-list {
            list-style: none;
        }

        .categories-list li {
            margin-bottom: 0.75rem;
        }

        .categories-list a {
            color: var(--primary-color);
            text-decoration: none;
            font-size: 1rem;
        }

        .categories-list a:hover {
            text-decoration: underline;
        }

        /* Blog List Page */
        .blog-grid {
            display: grid;
            gap: 2.5rem;
        }

        .blog-card {
            display: grid;
            grid-template-columns: 280px 1fr;
            gap: 1.5rem;
            padding-bottom: 2.5rem;
            border-bottom: 1px solid var(--border-color);
        }

        .blog-card:last-child {
            border-bottom: none;
        }

        .blog-thumbnail {
            width: 100%;
            height: 200px;
            object-fit: cover;
            border-radius: 4px;
        }

        .blog-content {
            display: flex;
            flex-direction: column;
        }

        .blog-category {
            color: var(--primary-color);
            font-weight: 600;
            font-size: 0.9rem;
            text-transform: uppercase;
            text-decoration: none;
            margin-bottom: 0.5rem;
            display: inline-block;
        }

        .blog-title {
            font-size: 1.5rem;
            font-weight: 700;
            line-height: 1.3;
            margin-bottom: 0.75rem;
        }

        .blog-title a {
            color: var(--text-dark);
            text-decoration: none;
        }

        .blog-title a:hover {
            color: var(--primary-color);
        }

        .blog-excerpt {
            color: var(--text-dark);
            line-height: 1.7;
            margin-bottom: 0.75rem;
        }

        /* Pagination */
        .pagination {
            display: flex;
            justify-content: center;
            gap: 0.5rem;
            margin: 3rem 0;
        }

        .pagination a,
        .pagination span {
            padding: 0.5rem 1rem;
            border: 1px solid var(--border-color);
            text-decoration: none;
            color: var(--text-dark);
            border-radius: 4px;
            transition: all 0.3s;
        }

        .pagination a:hover {
            background: var(--primary-color);
            color: var(--white);
            border-color: var(--primary-color);
        }

        .pagination .active {
            background: var(--primary-color);
            color: var(--white);
            border-color: var(--primary-color);
        }

        /* Footer */
        footer {
            background: var(--bg-light);
            border-top: 1px solid var(--border-color);
            padding: 2rem;
            margin-top: 4rem;
        }

        .footer-content {
            max-width: 1200px;
            margin: 0 auto;
            text-align: center;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin-bottom: 1.5rem;
            flex-wrap: wrap;
        }

        .footer-links a {
            color: var(--text-dark);
            text-decoration: none;
            font-size: 0.9rem;
        }

        .footer-links a:hover {
            color: var(--primary-color);
        }

        .copyright {
            color: var(--text-gray);
            font-size: 0.9rem;
        }

        /* Scroll to top button */
        .scroll-top {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            width: 50px;
            height: 50px;
            background: var(--primary-color);
            color: var(--white);
            border: none;
            border-radius: 4px;
            cursor: pointer;
            display: none;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            box-shadow: 0 4px 12px rgba(0,102,204,0.3);
            transition: all 0.3s;
        }

        .scroll-top:hover {
            background: #0052a3;
            transform: translateY(-2px);
        }

        .scroll-top.visible {
            display: flex;
        }

        /* Error Message */
        .error-message {
            text-align: center;
            padding: 4rem 2rem;
            color: var(--text-gray);
        }

        .error-message h2 {
            font-size: 2rem;
            margin-bottom: 1rem;
            color: var(--text-dark);
        }

        .error-message a {
            color: var(--primary-color);
            text-decoration: none;
        }

        /* Responsive */
        @media (max-width: 968px) {
            .container {
                grid-template-columns: 1fr;
            }

            aside {
                position: static;
            }

            .blog-card {
                grid-template-columns: 1fr;
            }

            .nav-links {
                gap: 1rem;
            }

            .article-title {
                font-size: 1.75rem;
            }
        }

        @media (max-width: 640px) {
            nav {
                flex-direction: column;
                gap: 1rem;
            }

            .nav-links {
                flex-wrap: wrap;
                justify-content: center;
            }

            .container {
                padding: 1rem;
            }
        }
/* Sidebar Styling */
.sidebar-section {
    margin-bottom: 2.5rem;
}

.sidebar-title {
    font-size: 1.2rem;
    border-left: 4px solid var(--primary-color);
    padding-left: 10px;
    margin-bottom: 1.5rem;
}

/* Recent Post Cards */
.post-card {
    display: flex;
    gap: 12px;
    margin-bottom: 1rem;
    align-items: center;
}

.post-thumbnail {
    width: 60px;
    height: 60px;
    border-radius: 6px;
    object-fit: cover;
}

.post-title {
    font-size: 0.9rem;
    line-height: 1.4;
}

/* Category List */
.categories-list {
    list-style: none;
}

.categories-list li {
    padding: 8px 0;
    border-bottom: 1px solid #eee;
}

.categories-list a {
    text-decoration: none;
    color: #333;
    display: block;
    transition: 0.2s;
}

.categories-list a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

/* Exact Footer Styles from index.html */
footer {
    background: var(--bg-light);
    border-top: 1px solid var(--border-color);
    padding: 2rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    list-style: none; /* Added to ensure no bullets */
    padding: 0;
}

.footer-links a {
    color: var(--text-dark);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--primary-color);
}

.copyright {
    color: var(--text-gray);
    font-size: 0.9rem;
}

/* Centered Table of Contents */
.toc {
    background: var(--bg-light);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    margin: 2.5rem auto; /* "auto" on the sides centers the block */
    
    /* Using display: table is the most reliable way to 
       center a box while matching its text width */
    display: table; 
    min-width: 320px;
    max-width: 100%;
}

.toc-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    text-align: center; /* Centers the "Table of Contents" title */
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.75rem;
}

.toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.toc-list li {
    margin-bottom: 0.85rem;
}

.toc-list a {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    display: flex;
    gap: 0.75rem;
    transition: all 0.2s ease;
}

.toc-list a:hover {
    color: var(--primary-color);
    transform: translateX(5px); /* Smooth crispy slide */
}
html {
    scroll-behavior: smooth;
    /* This ensures your sticky nav doesn't cover the heading 
       when the page auto-scrolls */
    scroll-padding-top: 100px; 
}
        /* Container spacing */
.container {
    max-width: 1200px;
    margin: 40px auto; /* Adds space at top/bottom and centers */
    padding: 0 20px;
    display: flex;
    gap: 40px; /* Crucial: This creates the gap between content and sidebar */
}

/* Main content width */
main {
    flex: 2; /* Takes up 2/3 of the space */
    min-width: 0; /* Prevents overflow */
}

/* Sidebar width */
aside {
    flex: 1; /* Takes up 1/3 of the space */
    display: flex;
    flex-direction: column;
    gap: 30px; /* Spaces out different sidebar widgets */
}/* Article Styling */
.article-title {
    font-size: 2.5rem;
    margin-bottom: 10px;
    color: #222;
    line-height: 1.2;
}

.article-meta {
    margin-bottom: 30px;
    color: #777;
    font-size: 0.9rem;
    border-bottom: 1px solid #eee;
    padding-bottom: 15px;
}

/* The actual text blocks */
.content p {
    line-height: 1.8; /* Makes text easier to read */
    margin-bottom: 20px;
    color: #444;
}

.content h2 {
    margin-top: 40px;
    margin-bottom: 15px;
    font-size: 1.8rem;
}

.content hr {
    margin: 40px 0;
    border: 0;
    border-top: 1px solid #eee;
}
.sidebar-title {
    font-size: 1.2rem;
    border-left: 4px solid #3498db; /* Adds a nice accent line */
    padding-left: 10px;
    margin-bottom: 20px;
    text-transform: uppercase;
}

.post-card {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    align-items: center;
}

.post-thumbnail {
    width: 80px;
    height: 60px;
    object-fit: cover;
    border-radius: 4px;
}

.post-title {
    font-size: 0.95rem;
    line-height: 1.4;
}

.categories-list li {
    list-style: none;
    padding: 10px 0;
    border-bottom: 1px solid #f0f0f0;
}