*,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, Roboto, 'Helvetica Neue', Arial, sans-serif;
            background: #f8f9fc;
            color: #1a1e2b;
            line-height: 1.7;
            padding: 0 1rem;
            max-width: 1280px;
            margin: 0 auto;
        }
        a {
            color: #2a6df4;
            text-decoration: none;
            transition: color 0.2s ease;
        }
        a:hover {
            color: #1a4fb3;
            text-decoration: underline;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: 10px;
        }
        h1,
        h2,
        h3,
        h4 {
            font-weight: 700;
            line-height: 1.25;
            margin-top: 2rem;
            margin-bottom: 0.75rem;
            color: #0f172a;
        }
        h1 {
            font-size: 2.4rem;
            margin-top: 1rem;
        }
        h2 {
            font-size: 1.8rem;
            border-bottom: 3px solid #e2e8f0;
            padding-bottom: 0.4rem;
        }
        h3 {
            font-size: 1.35rem;
            color: #1e293b;
        }
        h4 {
            font-size: 1.1rem;
            color: #334155;
        }
        p {
            margin-bottom: 1.25rem;
            font-size: 1.05rem;
        }
        ul,
        ol {
            margin: 0 0 1.5rem 1.75rem;
        }
        li {
            margin-bottom: 0.5rem;
        }
        hr {
            border: 0;
            height: 2px;
            background: linear-gradient(90deg, transparent, #cbd5e1, transparent);
            margin: 3rem 0;
        }
        .skip-link {
            position: absolute;
            top: -100%;
            left: 1rem;
            background: #2a6df4;
            color: #fff;
            padding: 0.5rem 1rem;
            border-radius: 0 0 6px 6px;
            z-index: 999;
        }
        .skip-link:focus {
            top: 0;
        }
        header {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            padding: 1rem 0;
            border-bottom: 1px solid #e2e8f0;
            margin-bottom: 1.2rem;
            position: relative;
        }
        .my-logo {
            font-size: 1.9rem;
            font-weight: 800;
            color: #0f172a;
            letter-spacing: -0.5px;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 0.3rem;
        }
        .my-logo:hover {
            text-decoration: none;
            color: #2a6df4;
        }
        .my-logo i {
            color: #2a6df4;
            font-size: 1.8rem;
        }
        nav.nav-primary {
            display: flex;
            align-items: center;
            gap: 0.2rem;
        }
        nav.nav-primary a {
            padding: 0.6rem 1rem;
            border-radius: 8px;
            font-weight: 500;
            font-size: 0.95rem;
            color: #1e293b;
            transition: background 0.2s, color 0.2s;
        }
        nav.nav-primary a:hover {
            background: #eef2ff;
            color: #2a6df4;
            text-decoration: none;
        }
        nav.nav-primary a.active {
            background: #2a6df4;
            color: #fff;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            font-size: 1.8rem;
            color: #0f172a;
            cursor: pointer;
            padding: 0.2rem 0.5rem;
            border-radius: 6px;
            transition: background 0.2s;
        }
        .hamburger:hover {
            background: #eef2ff;
        }
        .breadcrumb {
            font-size: 0.9rem;
            padding: 0.4rem 0 0.8rem 0;
            color: #64748b;
            display: flex;
            flex-wrap: wrap;
            gap: 0.4rem;
            align-items: center;
        }
        .breadcrumb a {
            color: #2a6df4;
        }
        .breadcrumb span {
            color: #94a3b8;
            margin: 0 0.2rem;
        }
        .hero {
            background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
            color: #f1f5f9;
            padding: 2.5rem 2rem;
            border-radius: 16px;
            margin: 1.2rem 0 2.5rem 0;
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            align-items: center;
            justify-content: space-between;
        }
        .hero-content {
            flex: 2 1 300px;
        }
        .hero-content h1 {
            color: #f8fafc;
            font-size: 2.2rem;
            margin-top: 0;
            border: none;
        }
        .hero-content p {
            font-size: 1.15rem;
            opacity: 0.9;
            max-width: 600px;
        }
        .hero-img {
            flex: 1 1 220px;
            border-radius: 12px;
            box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
        }
        .main-grid {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 2.5rem;
            margin: 1.5rem 0 3rem 0;
        }
        .content-area {
            min-width: 0;
        }
        .sidebar {
            background: #ffffff;
            border-radius: 14px;
            padding: 1.6rem 1.4rem;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04);
            border: 1px solid #e9edf4;
            height: fit-content;
            position: sticky;
            top: 1.5rem;
        }
        .sidebar h3 {
            margin-top: 0;
            font-size: 1.2rem;
            border-bottom: 2px solid #e2e8f0;
            padding-bottom: 0.5rem;
        }
        .sidebar ul {
            list-style: none;
            margin: 0.8rem 0 0 0;
            padding: 0;
        }
        .sidebar li {
            margin-bottom: 0.6rem;
        }
        .sidebar a {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.4rem 0.6rem;
            border-radius: 6px;
            transition: background 0.2s;
        }
        .sidebar a:hover {
            background: #f1f5f9;
            text-decoration: none;
        }
        .sidebar a i {
            width: 1.2rem;
            color: #2a6df4;
        }
        .search-box {
            background: #fff;
            border-radius: 12px;
            padding: 1.5rem 1.5rem 1.8rem;
            margin: 2rem 0;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
            border: 1px solid #e9edf4;
        }
        .search-box h3 {
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 0.6rem;
        }
        .search-form {
            display: flex;
            flex-wrap: wrap;
            gap: 0.8rem;
            margin-top: 0.8rem;
        }
        .search-form input[type="text"] {
            flex: 1 1 240px;
            padding: 0.75rem 1rem;
            border: 1px solid #cbd5e1;
            border-radius: 8px;
            font-size: 1rem;
            background: #f8fafc;
            transition: border 0.2s, box-shadow 0.2s;
        }
        .search-form input[type="text"]:focus {
            border-color: #2a6df4;
            box-shadow: 0 0 0 3px rgba(42, 109, 244, 0.15);
            outline: none;
        }
        .search-form button {
            padding: 0.75rem 1.8rem;
            background: #2a6df4;
            color: #fff;
            border: none;
            border-radius: 8px;
            font-weight: 600;
            font-size: 1rem;
            cursor: pointer;
            transition: background 0.2s, transform 0.1s;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .search-form button:hover {
            background: #1a4fb3;
            transform: translateY(-1px);
        }
        .interaction-panel {
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            margin: 2.5rem 0;
        }
        .comment-section,
        .rating-section {
            flex: 1 1 280px;
            background: #fff;
            border-radius: 14px;
            padding: 1.6rem 1.6rem 2rem;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
            border: 1px solid #e9edf4;
        }
        .comment-section h3,
        .rating-section h3 {
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 0.6rem;
        }
        .comment-section textarea,
        .rating-section select,
        .rating-section input[type="number"] {
            width: 100%;
            padding: 0.7rem 0.9rem;
            border: 1px solid #cbd5e1;
            border-radius: 8px;
            font-size: 0.95rem;
            font-family: inherit;
            background: #f8fafc;
            transition: border 0.2s;
            margin-bottom: 0.6rem;
        }
        .comment-section textarea:focus,
        .rating-section select:focus,
        .rating-section input[type="number"]:focus {
            border-color: #2a6df4;
            box-shadow: 0 0 0 3px rgba(42, 109, 244, 0.1);
            outline: none;
        }
        .comment-section textarea {
            min-height: 90px;
            resize: vertical;
        }
        .comment-section button,
        .rating-section button {
            padding: 0.65rem 1.6rem;
            background: #0f172a;
            color: #fff;
            border: none;
            border-radius: 8px;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.2s;
            font-size: 0.95rem;
        }
        .comment-section button:hover,
        .rating-section button:hover {
            background: #2a6df4;
        }
        .rating-stars {
            display: flex;
            gap: 0.3rem;
            font-size: 1.6rem;
            color: #f59e0b;
            margin: 0.4rem 0 0.8rem 0;
            cursor: pointer;
        }
        .rating-stars i {
            transition: transform 0.15s, color 0.15s;
        }
        .rating-stars i:hover {
            transform: scale(1.2);
        }
        .rating-display {
            font-weight: 600;
            margin-top: 0.3rem;
            color: #1e293b;
        }
        figure {
            margin: 2rem 0;
            text-align: center;
        }
        figure img {
            border-radius: 12px;
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.08);
        }
        figcaption {
            font-size: 0.9rem;
            color: #64748b;
            margin-top: 0.5rem;
            font-style: italic;
        }
        .callout {
            background: #eef2ff;
            border-left: 5px solid #2a6df4;
            padding: 1.2rem 1.6rem;
            border-radius: 0 10px 10px 0;
            margin: 1.8rem 0;
        }
        .callout p:last-child {
            margin-bottom: 0;
        }
        .table-wrap {
            overflow-x: auto;
            margin: 1.8rem 0;
        }
        table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.95rem;
            background: #fff;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
        }
        th,
        td {
            padding: 0.7rem 1rem;
            text-align: left;
            border-bottom: 1px solid #e9edf4;
        }
        th {
            background: #f1f5f9;
            font-weight: 600;
            color: #0f172a;
        }
        tr:last-child td {
            border-bottom: none;
        }
        footer {
            border-top: 1px solid #e2e8f0;
            padding: 2rem 0 1.5rem 0;
            margin-top: 3rem;
        }
        .footer-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            justify-content: space-between;
        }
        .footer-col {
            flex: 1 1 200px;
        }
        .footer-col h4 {
            margin-top: 0;
            font-size: 1.05rem;
            color: #0f172a;
        }
        .footer-col ul {
            list-style: none;
            margin: 0.5rem 0 0 0;
            padding: 0;
        }
        .footer-col li {
            margin-bottom: 0.4rem;
        }
        .footer-col a {
            color: #334155;
        }
        .footer-col a:hover {
            color: #2a6df4;
        }
        .copyright {
            text-align: center;
            padding-top: 1.5rem;
            margin-top: 1.5rem;
            border-top: 1px solid #e9edf4;
            color: #64748b;
            font-size: 0.9rem;
        }
        friend-link {
            display: flex;
            flex-wrap: wrap;
            gap: 0.8rem 1.6rem;
            padding: 1rem 0 0.5rem 0;
            font-size: 0.95rem;
        }
        friend-link a {
            color: #2a6df4;
        }
        friend-link a:hover {
            text-decoration: underline;
        }
        .last-updated {
            font-size: 0.9rem;
            color: #64748b;
            display: flex;
            align-items: center;
            gap: 0.4rem;
            margin: 0.4rem 0 1.2rem 0;
        }
        @media (max-width: 820px) {
            .main-grid {
                grid-template-columns: 1fr;
            }
            .sidebar {
                position: static;
                order: 2;
            }
            .content-area {
                order: 1;
            }
            .hero {
                flex-direction: column;
                text-align: center;
                padding: 2rem 1.2rem;
            }
            .hero-content p {
                max-width: 100%;
            }
            .hero-img {
                max-width: 280px;
            }
            h1 {
                font-size: 1.9rem;
            }
            h2 {
                font-size: 1.5rem;
            }
        }
        @media (max-width: 640px) {
            body {
                padding: 0 0.6rem;
            }
            header {
                flex-wrap: nowrap;
            }
            .hamburger {
                display: block;
            }
            nav.nav-primary {
                display: none;
                flex-direction: column;
                width: 100%;
                background: #ffffff;
                border-radius: 12px;
                padding: 0.6rem 0;
                box-shadow: 0 12px 30px rgba(0, 0, 0, 0.1);
                position: absolute;
                top: 100%;
                left: 0;
                z-index: 100;
                border: 1px solid #e9edf4;
                margin-top: 0.3rem;
            }
            nav.nav-primary.open {
                display: flex;
            }
            nav.nav-primary a {
                padding: 0.7rem 1.2rem;
                border-radius: 0;
            }
            .my-logo {
                font-size: 1.5rem;
            }
            .hero-content h1 {
                font-size: 1.6rem;
            }
            .interaction-panel {
                flex-direction: column;
            }
            .breadcrumb {
                font-size: 0.8rem;
            }
            .search-form button {
                width: 100%;
                justify-content: center;
            }
            .rating-stars {
                font-size: 1.4rem;
            }
            table {
                font-size: 0.85rem;
            }
            th,
            td {
                padding: 0.5rem 0.6rem;
            }
        }
        @media (min-width: 641px) {
            nav.nav-primary {
                display: flex !important;
            }
            .hamburger {
                display: none !important;
            }
        }
        .text-muted {
            color: #64748b;
        }
        .flex-center {
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .mt-1 {
            margin-top: 1rem;
        }
        .mb-1 {
            margin-bottom: 1rem;
        }
        .highlight {
            background: #fef9c3;
            padding: 0.1rem 0.3rem;
            border-radius: 4px;
            font-weight: 500;
        }
        .tag {
            display: inline-block;
            background: #e9edf4;
            padding: 0.2rem 0.8rem;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 500;
            color: #1e293b;
        }