*,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        body {
            font-family: 'Segoe UI', Roboto, system-ui, -apple-system, BlinkMacSystemFont, 'Helvetica Neue', sans-serif;
            background: #f6f8fc;
            color: #1a1a2e;
            line-height: 1.7;
            font-size: 16px;
        }
        a {
            color: #1e4a76;
            text-decoration: none;
            transition: color 0.2s;
        }
        a:hover {
            color: #0f2b44;
            text-decoration: underline;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: 12px;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }
        header {
            background: linear-gradient(145deg, #0b1a2a, #1a3349);
            color: #fff;
            padding: 16px 0;
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
        }
        .my-logo {
            font-size: 1.8rem;
            font-weight: 800;
            letter-spacing: -0.5px;
            background: linear-gradient(135deg, #f7971e, #ffd200);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            text-shadow: none;
            display: inline-block;
        }
        .my-logo i {
            -webkit-text-fill-color: #ffd200;
            margin-right: 6px;
        }
        .my-logo:hover {
            opacity: 0.9;
            text-decoration: none;
        }
        nav#main-nav {
            display: flex;
            align-items: center;
            gap: 8px;
            flex-wrap: wrap;
        }
        nav#main-nav a {
            color: #e0edf9;
            padding: 8px 14px;
            border-radius: 40px;
            font-weight: 500;
            font-size: 0.9rem;
            transition: background 0.25s, color 0.25s;
            white-space: nowrap;
        }
        nav#main-nav a:hover {
            background: rgba(255, 255, 255, 0.15);
            color: #ffd966;
            text-decoration: none;
        }
        nav#main-nav a.active {
            background: #f7971e;
            color: #0b1a2a;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: #fff;
            font-size: 1.8rem;
            cursor: pointer;
            padding: 4px 8px;
            border-radius: 8px;
            transition: background 0.2s;
        }
        .hamburger:hover {
            background: rgba(255, 255, 255, 0.1);
        }
        .breadcrumb {
            background: #e9eef3;
            padding: 12px 0;
            font-size: 0.85rem;
            border-bottom: 1px solid #d0dae6;
        }
        .breadcrumb ol {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            gap: 6px 12px;
        }
        .breadcrumb li+li::before {
            content: "›";
            margin-right: 12px;
            color: #687a8a;
            font-weight: 600;
        }
        .breadcrumb a {
            color: #1e4a76;
        }
        .breadcrumb .current {
            color: #4a5a6a;
            font-weight: 500;
        }
        .page-grid {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
            padding: 40px 0;
        }
        .main-content {
            min-width: 0;
        }
        .sidebar {
            position: sticky;
            top: 100px;
            align-self: start;
        }
        h1 {
            font-size: 2.6rem;
            font-weight: 800;
            line-height: 1.25;
            margin-bottom: 16px;
            color: #0b1a2a;
            letter-spacing: -0.02em;
        }
        h2 {
            font-size: 1.9rem;
            font-weight: 700;
            margin: 48px 0 16px;
            padding-bottom: 8px;
            border-bottom: 4px solid #f7971e;
            color: #0b1a2a;
            letter-spacing: -0.01em;
        }
        h3 {
            font-size: 1.4rem;
            font-weight: 600;
            margin: 32px 0 12px;
            color: #1a3349;
        }
        h4 {
            font-size: 1.15rem;
            font-weight: 600;
            margin: 24px 0 8px;
            color: #2a4a6a;
        }
        p {
            margin-bottom: 16px;
            color: #2c3e4e;
        }
        .lead {
            font-size: 1.2rem;
            color: #1a3349;
            font-weight: 400;
            line-height: 1.8;
        }
        strong {
            color: #0b1a2a;
        }
        .highlight-box {
            background: #eef4fa;
            border-left: 6px solid #f7971e;
            padding: 20px 24px;
            border-radius: 0 12px 12px 0;
            margin: 24px 0;
        }
        .highlight-box p:last-child {
            margin-bottom: 0;
        }
        .hero-img-wrap {
            margin: 28px 0 32px;
            border-radius: 16px;
            overflow: hidden;
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
            background: #dce3ec;
            position: relative;
        }
        .hero-img-wrap img {
            width: 100%;
            height: auto;
            max-height: 480px;
            object-fit: cover;
        }
        .hero-img-wrap .img-caption {
            padding: 12px 20px;
            background: #f0f4f9;
            font-size: 0.85rem;
            color: #4a5a6a;
            font-style: italic;
            border-top: 1px solid #d0dae6;
        }
        ul,
        ol {
            padding-left: 24px;
            margin-bottom: 20px;
        }
        li {
            margin-bottom: 6px;
        }
        .sidebar-card {
            background: #fff;
            border-radius: 16px;
            padding: 24px;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
            margin-bottom: 24px;
            border: 1px solid #e2e8f0;
        }
        .sidebar-card h3 {
            font-size: 1.2rem;
            margin-top: 0;
            margin-bottom: 12px;
            border-bottom: 2px solid #eef4fa;
            padding-bottom: 8px;
        }
        .sidebar-card ul {
            list-style: none;
            padding-left: 0;
        }
        .sidebar-card ul li {
            padding: 6px 0;
            border-bottom: 1px solid #f0f4f9;
        }
        .sidebar-card ul li:last-child {
            border-bottom: none;
        }
        .sidebar-card ul li a {
            font-weight: 500;
        }
        .search-form {
            display: flex;
            gap: 8px;
            margin: 20px 0 28px;
        }
        .search-form input {
            flex: 1;
            padding: 14px 18px;
            border: 2px solid #d0dae6;
            border-radius: 40px;
            font-size: 1rem;
            background: #fff;
            transition: border 0.3s;
            outline: none;
        }
        .search-form input:focus {
            border-color: #f7971e;
        }
        .search-form button {
            background: #1a3349;
            color: #fff;
            border: none;
            border-radius: 40px;
            padding: 0 28px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.25s;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .search-form button:hover {
            background: #0b1a2a;
        }
        .interaction-area {
            background: #fff;
            border-radius: 20px;
            padding: 32px;
            margin: 48px 0;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
            border: 1px solid #e2e8f0;
        }
        .interaction-area h2 {
            margin-top: 0;
            border-bottom-color: #f7971e;
        }
        .comment-form textarea,
        .comment-form input {
            width: 100%;
            padding: 14px 18px;
            border: 2px solid #d0dae6;
            border-radius: 12px;
            font-size: 1rem;
            margin-bottom: 16px;
            font-family: inherit;
            transition: border 0.3s;
            outline: none;
            background: #fafcff;
        }
        .comment-form textarea:focus,
        .comment-form input:focus {
            border-color: #f7971e;
        }
        .comment-form textarea {
            min-height: 120px;
            resize: vertical;
        }
        .form-row {
            display: flex;
            gap: 16px;
            flex-wrap: wrap;
        }
        .form-row input {
            flex: 1;
            min-width: 180px;
        }
        .btn {
            background: #1a3349;
            color: #fff;
            border: none;
            border-radius: 40px;
            padding: 14px 32px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.25s, transform 0.1s;
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }
        .btn:hover {
            background: #0b1a2a;
            transform: translateY(-1px);
            text-decoration: none;
            color: #fff;
        }
        .btn-secondary {
            background: #e9eef3;
            color: #1a3349;
        }
        .btn-secondary:hover {
            background: #d0dae6;
            color: #0b1a2a;
        }
        .star-rating {
            display: flex;
            gap: 6px;
            font-size: 1.8rem;
            cursor: pointer;
            margin: 12px 0 20px;
            direction: rtl;
        }
        .star-rating input {
            display: none;
        }
        .star-rating label {
            color: #c0c8d4;
            transition: color 0.2s;
            cursor: pointer;
        }
        .star-rating label:hover,
        .star-rating label:hover~label,
        .star-rating input:checked~label {
            color: #f7b731;
        }
        footer {
            background: #0b1a2a;
            color: #c8d6e5;
            padding: 48px 0 24px;
            margin-top: 48px;
        }
        footer a {
            color: #8ab4d6;
        }
        footer a:hover {
            color: #ffd966;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 32px;
        }
        .footer-grid h4 {
            color: #ffd966;
            margin-top: 0;
            font-weight: 600;
        }
        .footer-grid ul {
            list-style: none;
            padding-left: 0;
        }
        .footer-grid ul li {
            padding: 4px 0;
        }
        friend-link {
            display: block;
            background: #112233;
            padding: 24px 28px;
            border-radius: 16px;
            margin: 24px 0 32px;
            border: 1px solid #1e3a4a;
        }
        friend-link a {
            display: inline-block;
            margin: 4px 16px 4px 0;
            padding: 4px 0;
            font-weight: 500;
        }
        .copyright {
            border-top: 1px solid #1e3a4a;
            padding-top: 24px;
            font-size: 0.85rem;
            text-align: center;
            color: #7a8a9a;
        }
        @media (max-width: 820px) {
            .page-grid {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .sidebar {
                position: static;
            }
            .header-inner {
                flex-wrap: wrap;
            }
            .hamburger {
                display: block;
            }
            nav#main-nav {
                display: none;
                width: 100%;
                flex-direction: column;
                padding-top: 16px;
                gap: 4px;
            }
            nav#main-nav.open {
                display: flex;
            }
            nav#main-nav a {
                padding: 12px 16px;
                border-radius: 8px;
                width: 100%;
            }
            h1 {
                font-size: 2rem;
            }
            h2 {
                font-size: 1.5rem;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .form-row {
                flex-direction: column;
            }
            .search-form {
                flex-wrap: wrap;
            }
            .search-form button {
                width: 100%;
                justify-content: center;
                padding: 14px;
            }
        }
        @media (max-width: 480px) {
            .container {
                padding: 0 16px;
            }
            h1 {
                font-size: 1.6rem;
            }
            .interaction-area {
                padding: 20px;
            }
            .my-logo {
                font-size: 1.4rem;
            }
        }
        html {
            scroll-behavior: smooth;
        }
        .last-updated {
            display: flex;
            align-items: center;
            gap: 8px;
            color: #4a6a7a;
            font-size: 0.9rem;
            margin: 8px 0 24px;
            padding: 8px 16px;
            background: #eef4fa;
            border-radius: 40px;
            width: fit-content;
        }
        .last-updated i {
            color: #f7971e;
        }
        .toc-list {
            counter-reset: toc;
        }
        .toc-list li {
            counter-increment: toc;
        }
        .toc-list li a::before {
            content: counter(toc) ". ";
            color: #f7971e;
            font-weight: 600;
        }