/* CSS Variables for theming */
        :root {
            --primary-color: #e74c3c;
            --secondary-color: #e74c3c;
            --success-color: #2ecc71;
            --warning-color: #f1c40f;
            --dark-bg: #181818;
            --grad-top: #CFE9FF;
            --grad-mid: #B7DFFF;
            --grad-bottom: #A7D8FF;
            --light-bg: #e0f2f1;
            --white: #ffffff;
            --gray-50: #f9fafb;
            --gray-100: #f3f4f6;
            --gray-200: #e5e7eb;
            --gray-300: #d1d5db;
            --gray-400: #9ca3af;
            --gray-500: #6b7280;
            --gray-600: #4b5563;
            --gray-700: #374151;
            --gray-800: #1f2937;
            --gray-900: #111827;
            --blue-50: #eff6ff;
            --blue-200: #bfdbfe;
            --blue-300: #93c5fd;
            --blue-700: #1d4ed8;
            --blue-800: #1e40af;
            --blue-900: #1e3a8a;
            --green-50: #f0fdf4;
            --green-200: #bbf7d0;
            --green-300: #86efac;
            --green-700: #15803d;
            --green-800: #166534;
            --green-900: #14532d;
            --red-50: #fef2f2;
            --red-200: #fecaca;
            --red-300: #fca5a5;
            --red-700: #b91c1c;
            --red-800: #991b1b;
            --red-900: #7f1d1d;
            --yellow-100: #fef3c7;
            --yellow-900: #78350f;
            --purple-600: #9333ea;
        }

        /* Dark mode variables */
        .dark {
            --white: #1f2937;
            --gray-50: #1f2937;
            --gray-100: #374151;
            --gray-200: #4b5563;
            --gray-300: #6b7280;
            --gray-400: #9ca3af;
            --gray-500: #d1d5db;
            --gray-600: #e5e7eb;
            --gray-700: #f3f4f6;
            --gray-800: #1f2937;
            --gray-900: #111827;
            --blue-50: #1e3a8a;
            --blue-900: #eff6ff;
            --green-50: #14532d;
            --green-900: #f0fdf4;
            --red-50: #7f1d1d;
            --red-900: #fef2f2;
            --yellow-100: #78350f;
            --yellow-900: #fef3c7;
        }

        /* Reset and base styles */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            background-color: var(--light-bg);
            color: var(--gray-900);
            line-height: 1.6;
            min-height: 100vh;
            transition: all 0.3s ease;
        }

        .dark body {
            background-color: var(--dark-bg);
            color: var(--gray-100);
        }

        /* Container */
        .container {
            max-width: 1024px;
            margin: 0 auto;
            padding: 4px 12px;
        }

        @media (min-width: 640px) {
            .container {
                padding: 12px 24px;
            }
        }

        /* Reading Progress Bar */
        .reading-progress-wrapper {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 50;
        }

        .reading-progress {
            height: 3px;
            background: linear-gradient(90deg, #e74c3c 0%, #f39c12 50%, #27ae60 100%);
            transition: all 0.3s ease;
            width: 0%;
        }

        /* Header */
        .header {
            background: linear-gradient(to bottom, var(--grad-top), var(--grad-mid), var(--grad-bottom));
            color: var(--gray-800);
            border-radius: 16px;
            padding: 16px;
            margin-bottom: 16px;
            position: relative;
            overflow: hidden;
        }

        @media (min-width: 640px) {
            .header {
                padding: 24px;
                margin-bottom: 24px;
            }
        }

        /* Navigation */
        .nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 24px;
        }

        .logo {
            font-size: 20px;
            font-weight: 700;
            text-decoration: none;
            color: inherit;
            transition: color 0.3s ease;
        }

        .logo:hover {
            color: var(--primary-color);
        }

        @media (min-width: 640px) {
            .logo {
                font-size: 24px;
            }
        }

        .nav-links {
            display: none;
            gap: 24px;
        }

        @media (min-width: 640px) {
            .nav-links {
                display: flex;
            }
        }

        .nav-links a {
            text-decoration: none;
            color: inherit;
            transition: color 0.3s ease;
        }

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

        .nav-links a.active {
            font-weight: 600;
        }

        .mobile-menu-btn {
            display: block;
            background: none;
            border: none;
            color: var(--gray-700);
            font-size: 20px;
            cursor: pointer;
        }

        @media (min-width: 640px) {
            .mobile-menu-btn {
                display: none;
            }
        }

        /* Breadcrumb */
        .breadcrumb {
            display: flex;
            align-items: center;
            font-size: 14px;
            opacity: 0.75;
            margin-bottom: 16px;
        }

        .breadcrumb a {
            color: inherit;
            text-decoration: none;
            transition: color 0.3s ease;
        }

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

        .breadcrumb .separator {
            margin: 0 8px;
        }

        /* Article */
        .article {
            background: var(--white);
            border-radius: 16px;
            box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
            overflow: hidden;
        }

        .dark .article {
            background: var(--gray-800);
        }

        /* Article Header */
        .article-header {
            padding: 24px;
            border-bottom: 1px solid var(--gray-200);
        }

        .dark .article-header {
            border-bottom-color: var(--gray-700);
        }

        @media (min-width: 640px) {
            .article-header {
                padding: 32px;
            }
        }

        .article-title {
            font-size: 28px;
            font-weight: 700;
            color: var(--gray-900);
            margin-bottom: 16px;
            line-height: 1.2;
        }

        .dark .article-title {
            color: var(--white);
        }

        @media (min-width: 640px) {
            .article-title {
                font-size: 36px;
            }
        }

        .article-subtitle {
            font-size: 20px;
            color: var(--gray-600);
            margin-bottom: 24px;
            line-height: 1.5;
        }

        .dark .article-subtitle {
            color: var(--gray-400);
        }

        /* Article Meta */
        .article-meta {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            font-size: 14px;
            color: var(--gray-500);
        }

        .dark .article-meta {
            color: var(--gray-400);
        }

        .meta-item {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .category-tag {
            background: rgba(231, 76, 60, 0.1);
            color: var(--primary-color);
            padding: 4px 8px;
            border-radius: 4px;
            font-size: 12px;
        }

        /* Table of Contents */
        .toc {
            padding: 24px;
            background: var(--gray-50);
            border-bottom: 1px solid var(--gray-200);
        }

        .dark .toc {
            background: var(--gray-900);
            border-bottom-color: var(--gray-700);
        }

        @media (min-width: 640px) {
            .toc {
                padding: 32px;
            }
        }

        .toc-title {
            font-size: 18px;
            font-weight: 600;
            margin-bottom: 16px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .toc-list {
            list-style: none;
            font-size: 14px;
        }

        .toc-list li {
            margin-bottom: 8px;
        }

        .toc-link {
            color: inherit;
            text-decoration: none;
            transition: color 0.3s ease;
        }

        .toc-link:hover,
        .toc-link.active {
            color: var(--primary-color);
        }

        .toc-link.active {
            font-weight: 600;
        }

        /* Blog Content */
        .blog-content {
            padding: 24px;
        }

        @media (min-width: 640px) {
            .blog-content {
                padding: 32px;
            }
        }

        .blog-content h1 {
            font-size: 28px;
            font-weight: 700;
            margin-top: 32px;
            margin-bottom: 16px;
            color: var(--gray-900);
        }

        .dark .blog-content h1 {
            color: var(--white);
        }

        .blog-content h2 {
            font-size: 24px;
            font-weight: 700;
            margin-top: 24px;
            margin-bottom: 12px;
            color: var(--gray-900);
        }

        .dark .blog-content h2 {
            color: var(--white);
        }

        .blog-content h3 {
            font-size: 20px;
            font-weight: 600;
            margin-top: 20px;
            margin-bottom: 12px;
            color: var(--gray-800);
        }

        .dark .blog-content h3 {
            color: var(--gray-200);
        }

        .blog-content h4 {
            font-size: 18px;
            font-weight: 600;
            margin-top: 16px;
            margin-bottom: 8px;
            color: var(--gray-800);
        }

        .dark .blog-content h4 {
            color: var(--gray-200);
        }

        .blog-content p {
            margin-bottom: 16px;
            line-height: 1.7;
            color: var(--gray-700);
        }

        .dark .blog-content p {
            color: var(--gray-300);
        }

        .blog-content ul,
        .blog-content ol {
            margin-bottom: 16px;
            padding-left: 24px;
        }

        .blog-content ul li,
        .blog-content ol li {
            margin-bottom: 8px;
            color: var(--gray-700);
        }

        .dark .blog-content ul li,
        .dark .blog-content ol li {
            color: var(--gray-300);
        }

        .blog-content ul li {
            list-style-type: disc;
        }

        .blog-content ol li {
            list-style-type: decimal;
        }

        .blog-content blockquote {
            border-left: 4px solid var(--primary-color);
            padding: 8px 16px;
            background: var(--gray-50);
            border-radius: 0 8px 8px 0;
            margin-bottom: 16px;
            font-style: italic;
        }

        .dark .blog-content blockquote {
            background: var(--gray-800);
        }

        .blog-content code {
            background: var(--gray-100);
            padding: 2px 8px;
            border-radius: 4px;
            font-size: 14px;
            font-family: 'Courier New', monospace;
        }

        .dark .blog-content code {
            background: var(--gray-800);
        }

        .blog-content pre {
            background: var(--gray-100);
            padding: 16px;
            border-radius: 8px;
            margin-bottom: 16px;
            overflow-x: auto;
        }

        .dark .blog-content pre {
            background: var(--gray-800);
        }

        .blog-content a {
            color: var(--primary-color);
            text-decoration: underline;
            transition: color 0.3s ease;
        }

        .blog-content a:hover {
            color: rgba(231, 76, 60, 0.8);
        }

        .blog-content img {
            border-radius: 8px;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
            margin-bottom: 16px;
            max-width: 100%;
            height: auto;
        }

        .blog-content .highlight {
            background: var(--yellow-100);
            padding: 2px 8px;
            border-radius: 4px;
        }

        .dark .blog-content .highlight {
            background: var(--yellow-900);
        }

        /* Info boxes */
        .info-box {
            border-radius: 8px;
            padding: 16px;
            margin: 24px 0;
            border: 1px solid;
        }

        .info-box.blue {
            background: var(--blue-50);
            border-color: var(--blue-200);
        }

        .dark .info-box.blue {
            background: rgba(30, 58, 138, 0.2);
            border-color: var(--blue-800);
        }

        .info-box.green {
            background: var(--green-50);
            border-color: var(--green-200);
        }

        .dark .info-box.green {
            background: rgba(20, 83, 45, 0.2);
            border-color: var(--green-800);
        }

        .info-box.red {
            background: var(--red-50);
            border-color: var(--red-200);
        }

        .dark .info-box.red {
            background: rgba(127, 29, 29, 0.2);
            border-color: var(--red-800);
        }

        .info-box h4 {
            font-weight: 600;
            margin-bottom: 8px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .info-box.blue h4 {
            color: var(--blue-800);
        }

        .dark .info-box.blue h4 {
            color: var(--blue-300);
        }

        .info-box.green h4 {
            color: var(--green-800);
        }

        .dark .info-box.green h4 {
            color: var(--green-300);
        }

        .info-box.red h4 {
            color: var(--red-800);
        }

        .dark .info-box.red h4 {
            color: var(--red-300);
        }

        .info-box p,
        .info-box ul {
            margin-bottom: 0;
        }

        .info-box.blue p,
        .info-box.blue li {
            color: var(--blue-700);
        }

        .dark .info-box.blue p,
        .dark .info-box.blue li {
            color: var(--blue-300);
        }

        .info-box.green p,
        .info-box.green li {
            color: var(--green-700);
        }

        .dark .info-box.green p,
        .dark .info-box.green li {
            color: var(--green-300);
        }

        .info-box.red p,
        .info-box.red li {
            color: var(--red-700);
        }

        .dark .info-box.red p,
        .dark .info-box.red li {
            color: var(--red-300);
        }

        /* Grid layouts */
        .grid {
            display: grid;
            gap: 24px;
        }

        @media (min-width: 768px) {
            .grid-2 {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (min-width: 1024px) {
            .grid-3 {
                grid-template-columns: repeat(3, 1fr);
            }
        }

        /* Frequency chart */
        .frequency-chart {
            background: var(--gray-50);
            border-radius: 8px;
            padding: 24px;
            margin: 24px 0;
        }

        .dark .frequency-chart {
            background: var(--gray-900);
        }

        .frequency-chart h4 {
            font-weight: 600;
            margin-bottom: 12px;
        }

        .frequency-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 8px;
            font-size: 14px;
            font-family: 'Courier New', monospace;
        }

        @media (min-width: 640px) {
            .frequency-grid {
                grid-template-columns: repeat(3, 1fr);
            }
        }

        /* Call to action */
        .cta-box {
            background: rgba(231, 76, 60, 0.1);
            border: 1px solid rgba(231, 76, 60, 0.2);
            border-radius: 8px;
            padding: 24px;
            margin: 16px;
        }

        @media (min-width: 640px) {
            .cta-box {
                padding: 32px;
                margin: 32px 24px;
            }
        }

        .cta-box h4 {
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 12px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .cta-box p {
            color: var(--gray-700);
            margin-bottom: 16px;
        }

        .dark .cta-box p {
            color: var(--gray-300);
        }

        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--primary-color);
            color: white;
            padding: 12px 24px;
            border-radius: 8px;
            text-decoration: none;
            font-weight: 500;
            transition: background-color 0.3s ease;
        }

        .btn:hover {
            background: rgba(231, 76, 60, 0.9);
        }

        /* Author Bio */
        .author-bio {
            padding: 24px;
            border-top: 1px solid var(--gray-200);
        }

        .dark .author-bio {
            border-top-color: var(--gray-700);
        }

        @media (min-width: 640px) {
            .author-bio {
                padding: 32px;
            }
        }

        .author-bio h3 {
            font-size: 18px;
            font-weight: 600;
            margin-bottom: 16px;
        }

        .author-info {
            display: flex;
            align-items: center;
            gap: 16px;
        }

        .author-avatar {
            width: 64px;
            height: 64px;
            border-radius: 50%;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
        }

        .author-text {
            color: var(--gray-700);
        }

        .dark .author-text {
            color: var(--gray-300);
        }

        /* Tags */
        .tags-section {
            padding: 24px;
            border-top: 1px solid var(--gray-200);
        }

        .dark .tags-section {
            border-top-color: var(--gray-700);
        }

        @media (min-width: 640px) {
            .tags-section {
                padding: 32px;
            }
        }

        .tags-section h3 {
            font-size: 18px;
            font-weight: 600;
            margin-bottom: 16px;
        }

        .tags-list {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }

        .tag {
            background: var(--gray-100);
            color: var(--gray-700);
            padding: 4px 12px;
            border-radius: 9999px;
            font-size: 14px;
        }

        .dark .tag {
            background: var(--gray-700);
            color: var(--gray-300);
        }

        /* Related Articles */
        .related-articles {
            margin-top: 32px;
            background: var(--white);
            border-radius: 16px;
            padding: 24px;
            box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
            margin-bottom: 5px;
        }

        .dark .related-articles {
            background: var(--gray-800);
        }

        @media (min-width: 640px) {
            .related-articles {
                padding: 32px;
            }
        }

        .related-articles h2 {
            font-size: 24px;
            font-weight: 700;
            margin-bottom: 24px;
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .related-article {
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .related-article:hover .related-article-title {
            color: var(--primary-color);
        }

        .related-article-title {
            font-weight: 600;
            margin-bottom: 8px;
            transition: color 0.3s ease;
        }

        .related-article-description {
            font-size: 14px;
            color: var(--gray-600);
            margin-bottom: 8px;
        }

        .dark .related-article-description {
            color: var(--gray-400);
        }

        .related-article-meta {
            font-size: 12px;
            color: var(--gray-500);
        }

        /* Footer */
        .footer {
            margin-top: 32px;
            text-align: center;
            padding: 24px 0;
            border-top: 1px solid var(--gray-200);
        }

        .dark .footer {
            border-top-color: var(--gray-700);
        }

        .footer-links {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 16px;
            margin-bottom: 16px;
        }

        @media (min-width: 640px) {
            .footer-links {
                gap: 24px;
            }
        }

        .footer-link {
            color: var(--gray-600);
            text-decoration: none;
            transition: color 0.3s ease;
            font-size: 14px;
        }

        .dark .footer-link {
            color: var(--gray-400);
        }

        @media (min-width: 640px) {
            .footer-link {
                font-size: 16px;
            }
        }

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

        .footer-copyright {
            color: var(--gray-500);
            font-size: 12px;
        }

        @media (min-width: 640px) {
            .footer-copyright {
                font-size: 14px;
            }
        }

        /* Responsive utilities */
        .hidden-mobile {
            display: none;
        }

        @media (min-width: 640px) {
            .hidden-mobile {
                display: block;
            }
        }

        .hidden-desktop {
            display: block;
        }

        @media (min-width: 640px) {
            .hidden-desktop {
                display: none;
            }
        }
  /* Related Articles link style (override blog-content link rule) */
.related-articles a {
  text-decoration: none;
  color: inherit;
}
.related-articles a:hover {
  text-decoration: none; /* keep it clean on hover too */
}