*,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            background: #f8fafc;
            color: #1e293b;
            line-height: 1.7;
            padding: 0 1rem;
        }
        a {
            color: #2563eb;
            text-decoration: none;
            transition: color 0.2s;
        }
        a:hover {
            color: #1d4ed8;
            text-decoration: underline;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: 12px;
        }
        ul,
        ol {
            padding-left: 1.5rem;
            margin-bottom: 1.2rem;
        }
        li {
            margin-bottom: 0.4rem;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            line-height: 1.25;
            color: #0f172a;
            margin-top: 2rem;
            margin-bottom: 0.75rem;
            font-weight: 700;
        }
        h1 {
            font-size: 2.4rem;
            margin-top: 0.5rem;
        }
        h2 {
            font-size: 1.8rem;
            border-bottom: 3px solid #e2e8f0;
            padding-bottom: 0.4rem;
        }
        h3 {
            font-size: 1.35rem;
        }
        h4 {
            font-size: 1.1rem;
            font-weight: 600;
        }
        p {
            margin-bottom: 1.2rem;
        }
        strong,
        b {
            font-weight: 700;
            color: #0f172a;
        }
        em {
            font-style: italic;
        }
        hr {
            border: none;
            border-top: 2px solid #e2e8f0;
            margin: 2.5rem 0;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1rem;
        }
        .site-header {
            background: linear-gradient(135deg, #ffffff 0%, #f1f5f9 100%);
            border-bottom: 2px solid #e2e8f0;
            padding: 0.8rem 0;
            position: sticky;
            top: 0;
            z-index: 100;
            backdrop-filter: blur(6px);
            background: rgba(255, 255, 255, 0.95);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 0.5rem 1rem;
        }
        .my-logo {
            font-size: 1.8rem;
            font-weight: 800;
            background: linear-gradient(135deg, #2563eb, #7c3aed);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            letter-spacing: -0.5px;
            text-transform: uppercase;
            display: inline-block;
        }
        .my-logo:hover {
            opacity: 0.85;
            text-decoration: none;
        }
        .my-logo small {
            font-size: 0.7rem;
            -webkit-text-fill-color: #64748b;
            color: #64748b;
            display: block;
            font-weight: 400;
            letter-spacing: 1px;
        }
        .nav-bar {
            display: flex;
            align-items: center;
            gap: 1.2rem;
            flex-wrap: wrap;
        }
        .nav-bar a {
            font-weight: 600;
            color: #334155;
            padding: 0.3rem 0;
            border-bottom: 2px solid transparent;
            transition: 0.2s;
        }
        .nav-bar a:hover {
            color: #2563eb;
            border-bottom-color: #2563eb;
            text-decoration: none;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            font-size: 1.8rem;
            color: #1e293b;
            cursor: pointer;
            padding: 0.2rem 0.4rem;
            transition: 0.2s;
        }
        .hamburger:hover {
            color: #2563eb;
        }
        #nav-toggle {
            display: none;
        }
        .nav-overlay {
            display: none;
        }
        .breadcrumb {
            background: #f1f5f9;
            padding: 0.6rem 1.2rem;
            border-radius: 40px;
            font-size: 0.9rem;
            margin: 1rem 0 1.8rem 0;
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 0.3rem 0.6rem;
        }
        .breadcrumb a {
            color: #475569;
        }
        .breadcrumb a:hover {
            color: #2563eb;
        }
        .breadcrumb .sep {
            color: #94a3b8;
            font-weight: 300;
        }
        .breadcrumb .current {
            color: #0f172a;
            font-weight: 600;
        }
        .search-wrap {
            background: #ffffff;
            border: 1px solid #e2e8f0;
            border-radius: 50px;
            padding: 0.3rem 0.3rem 0.3rem 1.2rem;
            display: flex;
            align-items: center;
            max-width: 360px;
            margin: 1.5rem auto 2rem auto;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
        }
        .search-wrap input {
            flex: 1;
            border: none;
            outline: none;
            background: transparent;
            padding: 0.6rem 0;
            font-size: 0.95rem;
            color: #1e293b;
            min-width: 0;
        }
        .search-wrap input::placeholder {
            color: #94a3b8;
        }
        .search-wrap button {
            background: #2563eb;
            border: none;
            color: #fff;
            padding: 0.6rem 1.4rem;
            border-radius: 50px;
            font-weight: 600;
            cursor: pointer;
            transition: 0.2s;
            font-size: 0.95rem;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .search-wrap button:hover {
            background: #1d4ed8;
        }
        .hero-img-wrap {
            margin: 2rem 0 2.5rem 0;
            border-radius: 16px;
            overflow: hidden;
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
        }
        .hero-img-wrap img {
            width: 100%;
            max-height: 480px;
            object-fit: cover;
        }
        .hero-caption {
            font-size: 0.9rem;
            color: #64748b;
            text-align: center;
            margin-top: 0.5rem;
            font-style: italic;
        }
        .toc {
            background: #ffffff;
            border: 1px solid #e2e8f0;
            border-left: 5px solid #2563eb;
            border-radius: 12px;
            padding: 1.5rem 1.8rem;
            margin: 2rem 0 2.5rem 0;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.03);
        }
        .toc h3 {
            margin-top: 0;
            font-size: 1.3rem;
            display: flex;
            align-items: center;
            gap: 0.6rem;
        }
        .toc ul {
            list-style: none;
            padding: 0;
            margin: 0.8rem 0 0 0;
            columns: 2 240px;
            column-gap: 2rem;
        }
        .toc li {
            margin-bottom: 0.5rem;
            break-inside: avoid;
        }
        .toc a {
            display: inline-block;
            padding: 0.2rem 0;
            font-weight: 500;
        }
        .feedback-section {
            display: flex;
            flex-wrap: wrap;
            gap: 1.2rem 2rem;
            background: #ffffff;
            border: 1px solid #e2e8f0;
            border-radius: 16px;
            padding: 2rem 2rem 2.2rem 2rem;
            margin: 3rem 0 2rem 0;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.03);
        }
        .feedback-section h3 {
            margin-top: 0;
            width: 100%;
            font-size: 1.4rem;
        }
        .comment-box,
        .score-box {
            flex: 1 1 260px;
        }
        .comment-box form,
        .score-box form {
            display: flex;
            flex-direction: column;
            gap: 0.6rem;
        }
        .comment-box textarea,
        .score-box select,
        .score-box input[type="number"] {
            padding: 0.7rem 1rem;
            border: 1px solid #cbd5e1;
            border-radius: 10px;
            font-size: 0.95rem;
            font-family: inherit;
            background: #fafbfc;
            transition: 0.2s;
            outline: none;
        }
        .comment-box textarea:focus,
        .score-box select:focus,
        .score-box input[type="number"]:focus {
            border-color: #2563eb;
            box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
        }
        .comment-box textarea {
            min-height: 100px;
            resize: vertical;
        }
        .feedback-section .btn {
            background: #2563eb;
            color: #fff;
            border: none;
            padding: 0.65rem 1.5rem;
            border-radius: 40px;
            font-weight: 600;
            cursor: pointer;
            transition: 0.2s;
            font-size: 0.95rem;
            align-self: flex-start;
        }
        .feedback-section .btn:hover {
            background: #1d4ed8;
            transform: translateY(-1px);
        }
        friend-link {
            display: block;
            background: #f1f5f9;
            border-radius: 16px;
            padding: 1.8rem 2rem;
            margin: 2.5rem 0 1.5rem 0;
            border: 1px solid #e2e8f0;
        }
        friend-link h3 {
            margin-top: 0;
            font-size: 1.2rem;
            display: flex;
            align-items: center;
            gap: 0.6rem;
            color: #1e293b;
        }
        friend-link ul {
            list-style: none;
            padding: 0;
            margin: 1rem 0 0 0;
            display: flex;
            flex-wrap: wrap;
            gap: 0.6rem 1.8rem;
        }
        friend-link li {
            margin: 0;
        }
        friend-link a {
            color: #2563eb;
            font-weight: 500;
        }
        friend-link a:hover {
            color: #1d4ed8;
        }
        .site-footer {
            border-top: 2px solid #e2e8f0;
            padding: 2rem 0 1.5rem 0;
            margin-top: 3rem;
            text-align: center;
            color: #64748b;
            font-size: 0.9rem;
        }
        .site-footer .copyright {
            font-weight: 500;
            color: #334155;
        }
        @media (max-width: 768px) {
            body {
                padding: 0 0.6rem;
            }
            h1 {
                font-size: 1.8rem;
            }
            h2 {
                font-size: 1.4rem;
            }
            h3 {
                font-size: 1.15rem;
            }
            .header-inner {
                flex-wrap: wrap;
            }
            .hamburger {
                display: block;
            }
            .nav-bar {
                display: none;
                width: 100%;
                flex-direction: column;
                align-items: flex-start;
                gap: 0.3rem;
                padding: 1rem 0 0.5rem 0;
                border-top: 1px solid #e2e8f0;
                margin-top: 0.5rem;
            }
            #nav-toggle:checked+.hamburger+.nav-bar {
                display: flex;
            }
            .nav-bar a {
                padding: 0.5rem 0;
                width: 100%;
                border-bottom: 1px solid #f1f5f9;
            }
            .breadcrumb {
                font-size: 0.8rem;
                padding: 0.4rem 1rem;
                border-radius: 30px;
            }
            .toc ul {
                columns: 1;
            }
            .feedback-section {
                padding: 1.5rem;
            }
            .search-wrap {
                max-width: 100%;
            }
            friend-link ul {
                flex-direction: column;
                gap: 0.3rem;
            }
            .my-logo {
                font-size: 1.4rem;
            }
        }
        @media (min-width: 769px) {
            #nav-toggle {
                display: none;
            }
            .hamburger {
                display: none !important;
            }
            .nav-bar {
                display: flex !important;
            }
        }
        .text-muted {
            color: #64748b;
        }
        .mt-1 {
            margin-top: 1rem;
        }
        .mb-1 {
            margin-bottom: 1rem;
        }
        .flex-center {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            flex-wrap: wrap;
        }
        .last-updated {
            display: inline-block;
            background: #eef2ff;
            color: #4338ca;
            padding: 0.2rem 1rem;
            border-radius: 40px;
            font-size: 0.85rem;
            font-weight: 500;
            margin-bottom: 1.2rem;
        }
        .in-text-link {
            font-weight: 600;
            color: #2563eb;
            border-bottom: 1px dotted #94a3b8;
        }
        .in-text-link:hover {
            border-bottom-style: solid;
        }
        .stat-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
            gap: 1rem;
            margin: 1.8rem 0;
        }
        .stat-card {
            background: #ffffff;
            border: 1px solid #e2e8f0;
            border-radius: 16px;
            padding: 1.2rem;
            text-align: center;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
        }
        .stat-card .num {
            font-size: 2rem;
            font-weight: 800;
            color: #2563eb;
            display: block;
            line-height: 1.2;
        }
        .stat-card .label {
            font-size: 0.85rem;
            color: #64748b;
            text-transform: uppercase;
            letter-spacing: 0.5px;
            font-weight: 600;
        }
        .highlight-box {
            background: #fef9c3;
            border-left: 5px solid #eab308;
            padding: 1.2rem 1.5rem;
            border-radius: 0 12px 12px 0;
            margin: 1.8rem 0;
        }
        .highlight-box strong {
            color: #a16207;
        }
        .tip-box {
            background: #ecfdf5;
            border-left: 5px solid #10b981;
            padding: 1.2rem 1.5rem;
            border-radius: 0 12px 12px 0;
            margin: 1.8rem 0;
        }
        .tip-box strong {
            color: #047857;
        }
        .emoji-lg {
            font-size: 1.4rem;
        }