*,
        *::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, sans-serif;
            background: #f6f9fc;
            color: #1a2a3a;
            line-height: 1.7;
            padding: 0 1rem;
        }
        a {
            color: #0077b6;
            text-decoration: none;
            transition: color 0.2s;
        }
        a:hover {
            color: #023e8a;
            text-decoration: underline;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: 12px;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            background: #fff;
            box-shadow: 0 0 40px rgba(0, 0, 0, 0.04);
            border-radius: 24px;
            padding: 0 1.5rem 2rem;
        }
        h1 {
            font-size: 2.6rem;
            font-weight: 800;
            color: #0b2a3b;
            margin: 1.8rem 0 0.6rem;
            line-height: 1.2;
            letter-spacing: -0.02em;
        }
        h2 {
            font-size: 2rem;
            font-weight: 700;
            color: #0d3b4f;
            margin: 2.8rem 0 1rem 0;
            border-left: 6px solid #ffb347;
            padding-left: 1rem;
        }
        h3 {
            font-size: 1.5rem;
            font-weight: 600;
            color: #1e4a5f;
            margin: 2rem 0 0.7rem 0;
        }
        h4 {
            font-size: 1.2rem;
            font-weight: 600;
            color: #2a5f74;
            margin: 1.4rem 0 0.5rem 0;
        }
        p {
            margin-bottom: 1.2rem;
        }
        .lead {
            font-size: 1.2rem;
            color: #2c3e50;
            font-weight: 400;
            border-left: 4px solid #ffb347;
            padding-left: 1.2rem;
            background: #fef9f0;
            padding: 1rem 1.5rem;
            border-radius: 0 12px 12px 0;
        }
        hr {
            border: none;
            border-top: 2px solid #e8edf0;
            margin: 2.5rem 0;
        }
        header {
            padding: 1.2rem 0 0.6rem;
            border-bottom: 1px solid #e8edf0;
        }
        .header-top {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            gap: 0.8rem;
        }
        .my-logo {
            font-size: 1.8rem;
            font-weight: 800;
            background: linear-gradient(135deg, #ff6b6b, #ffb347);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            letter-spacing: -0.03em;
            display: inline-block;
        }
        .my-logo small {
            font-size: 0.9rem;
            font-weight: 400;
            -webkit-text-fill-color: #5a7a8a;
            color: #5a7a8a;
            background: none;
        }
        .my-logo:hover {
            opacity: 0.85;
            text-decoration: none;
        }
        .nav-toggle {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: #1a2a3a;
            cursor: pointer;
            padding: 0.2rem 0.5rem;
            border-radius: 8px;
            transition: background 0.2s;
        }
        .nav-toggle:hover {
            background: #eef3f7;
        }
        nav.main-nav {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 0.2rem 1.4rem;
        }
        nav.main-nav a {
            font-weight: 500;
            color: #1a3a4a;
            padding: 0.3rem 0;
            border-bottom: 2px solid transparent;
            transition: border-color 0.2s, color 0.2s;
            font-size: 0.95rem;
        }
        nav.main-nav a:hover {
            border-bottom-color: #ffb347;
            color: #0b2a3b;
            text-decoration: none;
        }
        nav.main-nav a i {
            margin-right: 0.3rem;
            font-size: 0.85rem;
        }
        .breadcrumb {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 0.3rem 0.5rem;
            padding: 0.8rem 0 0.2rem;
            font-size: 0.85rem;
            color: #6a7e8e;
        }
        .breadcrumb a {
            color: #4a6a7a;
        }
        .breadcrumb a:hover {
            color: #0077b6;
        }
        .breadcrumb i {
            font-size: 0.6rem;
            color: #9aabba;
        }
        .search-bar {
            display: flex;
            gap: 0.4rem;
            margin: 1.2rem 0 0.2rem;
            max-width: 520px;
        }
        .search-bar input {
            flex: 1;
            padding: 0.7rem 1rem;
            border: 2px solid #dce4e8;
            border-radius: 40px;
            font-size: 0.95rem;
            outline: none;
            transition: border-color 0.25s;
            background: #fafcfd;
        }
        .search-bar input:focus {
            border-color: #ffb347;
        }
        .search-bar button {
            background: #ffb347;
            border: none;
            border-radius: 40px;
            padding: 0 1.4rem;
            font-size: 1rem;
            color: #1a2a3a;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.2s, transform 0.1s;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .search-bar button:hover {
            background: #ff9f1c;
            transform: scale(1.02);
        }
        .search-bar button i {
            font-size: 0.9rem;
        }
        .hero-img {
            margin: 1.8rem 0 1.2rem;
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
            background: #eef3f7;
        }
        .hero-img img {
            width: 100%;
            display: block;
        }
        .img-caption {
            font-size: 0.8rem;
            color: #7a8e9e;
            text-align: right;
            padding: 0.4rem 0.8rem 0.2rem;
        }
        .table-wrap {
            overflow-x: auto;
            margin: 1.5rem 0;
            border-radius: 12px;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
        }
        table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.95rem;
            background: #fff;
        }
        th,
        td {
            padding: 0.8rem 1rem;
            text-align: left;
            border-bottom: 1px solid #e8edf0;
        }
        th {
            background: #f2f6f9;
            font-weight: 600;
            color: #0d3b4f;
        }
        tr:hover td {
            background: #fafbfc;
        }
        .interaction-section {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 2rem;
            margin: 2.5rem 0;
            padding: 1.8rem 2rem;
            background: #fafcfd;
            border-radius: 20px;
            border: 1px solid #e8edf0;
        }
        .interaction-section h3 {
            margin-top: 0;
            font-size: 1.3rem;
        }
        .interaction-section form {
            display: flex;
            flex-direction: column;
            gap: 0.8rem;
        }
        .interaction-section input,
        .interaction-section textarea,
        .interaction-section select {
            padding: 0.7rem 1rem;
            border: 2px solid #dce4e8;
            border-radius: 10px;
            font-size: 0.95rem;
            outline: none;
            transition: border-color 0.25s;
            background: #fff;
            font-family: inherit;
        }
        .interaction-section input:focus,
        .interaction-section textarea:focus,
        .interaction-section select:focus {
            border-color: #ffb347;
        }
        .interaction-section textarea {
            min-height: 80px;
            resize: vertical;
        }
        .interaction-section button {
            background: #0d3b4f;
            color: #fff;
            border: none;
            padding: 0.7rem 1.6rem;
            border-radius: 40px;
            font-weight: 600;
            font-size: 0.95rem;
            cursor: pointer;
            transition: background 0.2s, transform 0.1s;
            align-self: flex-start;
        }
        .interaction-section button:hover {
            background: #1a5a6f;
            transform: scale(1.02);
        }
        .rating-stars {
            display: flex;
            gap: 0.3rem;
            font-size: 1.8rem;
            color: #f0c040;
        }
        .rating-stars i {
            cursor: pointer;
            transition: transform 0.15s, color 0.2s;
        }
        .rating-stars i:hover {
            transform: scale(1.2);
            color: #ffb347;
        }
        friend-link {
            display: block;
            padding: 2rem 0 0.8rem;
            border-top: 2px solid #e8edf0;
            margin-top: 2.5rem;
        }
        friend-link h4 {
            font-size: 1.1rem;
            margin-bottom: 0.8rem;
            color: #0d3b4f;
        }
        friend-link a {
            display: inline-block;
            margin: 0.3rem 1.2rem 0.3rem 0;
            color: #4a6a7a;
            font-weight: 500;
        }
        friend-link a:hover {
            color: #0077b6;
        }
        footer {
            padding: 1.8rem 0 0.8rem;
            text-align: center;
            color: #6a7e8e;
            font-size: 0.9rem;
            border-top: 1px solid #e8edf0;
            margin-top: 2rem;
        }
        footer .copyright {
            margin-top: 0.4rem;
            font-size: 0.8rem;
            color: #8a9eae;
        }
        @media (max-width: 820px) {
            .container {
                padding: 0 1rem 1.5rem;
            }
            h1 {
                font-size: 2rem;
            }
            h2 {
                font-size: 1.6rem;
            }
            h3 {
                font-size: 1.25rem;
            }
            .interaction-section {
                grid-template-columns: 1fr;
                padding: 1.2rem;
            }
            .header-top {
                flex-wrap: wrap;
            }
            .nav-toggle {
                display: block;
            }
            nav.main-nav {
                display: none;
                flex-direction: column;
                width: 100%;
                padding: 0.8rem 0 0.2rem;
                gap: 0.4rem;
            }
            nav.main-nav.open {
                display: flex;
            }
            nav.main-nav a {
                padding: 0.5rem 0;
                border-bottom: 1px solid #e8edf0;
                width: 100%;
            }
            .search-bar {
                max-width: 100%;
            }
            .rating-stars {
                font-size: 1.5rem;
            }
        }
        @media (max-width: 480px) {
            h1 {
                font-size: 1.6rem;
            }
            .my-logo {
                font-size: 1.4rem;
            }
            .breadcrumb {
                font-size: 0.75rem;
            }
            .container {
                padding: 0 0.6rem 1rem;
                border-radius: 12px;
            }
            .interaction-section {
                padding: 1rem;
            }
        }
        .highlight {
            background: #fef3e0;
            padding: 0.1rem 0.4rem;
            border-radius: 6px;
            font-weight: 600;
        }
        .badge {
            display: inline-block;
            background: #ffb347;
            color: #1a2a3a;
            padding: 0.1rem 0.8rem;
            border-radius: 40px;
            font-size: 0.75rem;
            font-weight: 700;
            letter-spacing: 0.03em;
        }
        .quote {
            background: #f2f6f9;
            border-left: 5px solid #ffb347;
            padding: 1.2rem 1.8rem;
            border-radius: 0 12px 12px 0;
            margin: 1.5rem 0;
            font-style: italic;
            color: #2c4a5a;
        }
        .emoji-lg {
            font-size: 1.4em;
            display: inline-block;
            margin-right: 0.2em;
        }
        .grid-2 {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 1.5rem;
            margin: 1.5rem 0;
        }
        @media (max-width: 600px) {
            .grid-2 {
                grid-template-columns: 1fr;
            }
        }
        .card {
            background: #fafcfd;
            border: 1px solid #e8edf0;
            border-radius: 16px;
            padding: 1.2rem 1.5rem;
            transition: box-shadow 0.25s;
        }
        .card:hover {
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
        }
        .toc {
            background: #f2f6f9;
            border-radius: 16px;
            padding: 1.5rem 2rem;
            margin: 1.8rem 0;
        }
        .toc ul {
            list-style: none;
            padding: 0;
            columns: 2;
            column-gap: 2rem;
        }
        .toc li {
            padding: 0.2rem 0;
            break-inside: avoid;
        }
        .toc a {
            font-weight: 500;
        }
        @media (max-width: 500px) {
            .toc ul {
                columns: 1;
            }
        }