*,
        *::before,
        *::after {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            background: #f5f7fc;
            color: #1a1a2e;
            line-height: 1.7;
            -webkit-font-smoothing: antialiased;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        a {
            color: #0057b3;
            text-decoration: none;
            transition: color 0.2s;
        }
        a:hover {
            color: #ff6b00;
            text-decoration: underline;
        }
        ul,
        ol {
            padding-left: 1.5rem;
            margin-bottom: 1.2rem;
        }
        li {
            margin-bottom: 0.4rem;
        }
        p {
            margin-bottom: 1.2rem;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            font-weight: 700;
            line-height: 1.3;
            margin-top: 0;
            color: #0d1b2a;
        }
        h1 {
            font-size: 2.4rem;
            margin-bottom: 1rem;
        }
        h2 {
            font-size: 1.8rem;
            margin-top: 2.8rem;
            margin-bottom: 0.9rem;
            border-bottom: 3px solid #ff6b00;
            padding-bottom: 0.4rem;
            display: inline-block;
        }
        h3 {
            font-size: 1.35rem;
            margin-top: 2rem;
            margin-bottom: 0.7rem;
            color: #1e3a5f;
        }
        h4 {
            font-size: 1.1rem;
            margin-top: 1.4rem;
            margin-bottom: 0.5rem;
            color: #2d4a6e;
        }
        .container {
            max-width: 1140px;
            margin: 0 auto;
            padding: 0 1.2rem;
        }
        .site-header {
            background: linear-gradient(135deg, #0d1b2a 0%, #1b2f4a 100%);
            color: #fff;
            padding: 0.8rem 0;
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: 0 4px 18px rgba(0, 0, 0, 0.15);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
        }
        .my-logo {
            font-size: 1.9rem;
            font-weight: 900;
            letter-spacing: -0.5px;
            background: linear-gradient(135deg, #f5a623, #ff6b00);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .my-logo i {
            -webkit-text-fill-color: #ff6b00;
            font-size: 1.8rem;
        }
        .my-logo:hover {
            text-decoration: none;
            opacity: 0.9;
        }
        .my-logo span {
            font-size: 1rem;
            font-weight: 400;
            -webkit-text-fill-color: #aaa;
            margin-left: 0.3rem;
        }
        .main-nav {
            display: flex;
            align-items: center;
            gap: 0.2rem;
            flex-wrap: wrap;
        }
        .main-nav a {
            color: #e0e8f0;
            padding: 0.5rem 0.9rem;
            border-radius: 30px;
            font-size: 0.9rem;
            font-weight: 500;
            transition: all 0.2s;
            white-space: nowrap;
        }
        .main-nav a:hover,
        .main-nav a.active {
            background: rgba(255, 107, 0, 0.25);
            color: #fff;
            text-decoration: none;
        }
        .main-nav a i {
            margin-right: 0.35rem;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: #fff;
            font-size: 1.8rem;
            cursor: pointer;
            padding: 0.2rem 0.4rem;
        }
        .breadcrumb {
            background: #e9edf5;
            padding: 0.6rem 0;
            font-size: 0.85rem;
            border-bottom: 1px solid #d0d8e4;
        }
        .breadcrumb ol {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            gap: 0.3rem;
            padding: 0;
            margin: 0;
        }
        .breadcrumb li+li::before {
            content: "›";
            margin: 0 0.4rem;
            color: #7a8aa0;
        }
        .breadcrumb a {
            color: #0057b3;
        }
        .breadcrumb .current {
            color: #4a5a70;
            font-weight: 600;
        }
        .main-content {
            padding: 2rem 0 3rem;
        }
        .last-updated {
            display: inline-block;
            background: #eef2f7;
            padding: 0.3rem 1rem;
            border-radius: 30px;
            font-size: 0.8rem;
            color: #4a5a70;
            margin-bottom: 1.5rem;
            border: 1px solid #d0d8e4;
        }
        .last-updated i {
            margin-right: 0.4rem;
            color: #ff6b00;
        }
        .feature-image-wrap {
            margin: 1.8rem 0 2.2rem;
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
        }
        .feature-image-wrap img {
            width: 100%;
            display: block;
        }
        .feature-image-wrap figcaption {
            background: #f0f3f8;
            padding: 0.6rem 1.2rem;
            font-size: 0.85rem;
            color: #3a4a5e;
            border-top: 1px solid #dce2ec;
        }
        .toc {
            background: #fff;
            border: 1px solid #dce2ec;
            border-radius: 14px;
            padding: 1.4rem 2rem;
            margin: 2rem 0 2.8rem;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.03);
        }
        .toc summary {
            font-weight: 700;
            font-size: 1.2rem;
            cursor: pointer;
            color: #0d1b2a;
        }
        .toc ol {
            margin-top: 0.8rem;
            margin-bottom: 0;
            columns: 2;
            column-gap: 2rem;
            list-style: decimal;
        }
        .toc ol li {
            margin-bottom: 0.3rem;
            break-inside: avoid;
        }
        .toc a {
            color: #0057b3;
        }
        .highlight-box {
            background: linear-gradient(135deg, #fef7f0, #fff5eb);
            border-left: 5px solid #ff6b00;
            border-radius: 0 14px 14px 0;
            padding: 1.2rem 1.8rem;
            margin: 1.8rem 0;
            box-shadow: 0 2px 8px rgba(255, 107, 0, 0.08);
        }
        .highlight-box strong {
            color: #b34100;
        }
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 1.4rem;
            margin: 2rem 0;
        }
        .card-grid .card {
            background: #fff;
            border-radius: 14px;
            padding: 1.4rem 1.2rem;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
            border: 1px solid #e8ecf4;
            transition: transform 0.2s, box-shadow 0.2s;
        }
        .card-grid .card:hover {
            transform: translateY(-4px);
            box-shadow: 0 8px 28px rgba(0, 0, 0, 0.08);
        }
        .card-grid .card i {
            font-size: 2rem;
            color: #ff6b00;
            margin-bottom: 0.6rem;
        }
        .card-grid .card h4 {
            margin-top: 0;
        }
        .form-section {
            background: #fff;
            border-radius: 16px;
            padding: 1.8rem 2rem;
            margin: 2.4rem 0;
            border: 1px solid #e0e6f0;
            box-shadow: 0 4px 14px rgba(0, 0, 0, 0.03);
        }
        .form-section h3 {
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 0.6rem;
        }
        .form-group {
            margin-bottom: 1.2rem;
        }
        .form-group label {
            font-weight: 600;
            display: block;
            margin-bottom: 0.3rem;
            font-size: 0.9rem;
        }
        .form-group input,
        .form-group textarea,
        .form-group select {
            width: 100%;
            padding: 0.7rem 1rem;
            border: 1px solid #ccd4e0;
            border-radius: 10px;
            font-size: 0.95rem;
            font-family: inherit;
            background: #fafbfd;
            transition: border 0.2s;
        }
        .form-group input:focus,
        .form-group textarea:focus {
            border-color: #ff6b00;
            outline: none;
            box-shadow: 0 0 0 3px rgba(255, 107, 0, 0.15);
        }
        .form-group textarea {
            min-height: 100px;
            resize: vertical;
        }
        .btn {
            background: #ff6b00;
            color: #fff;
            border: none;
            padding: 0.7rem 2rem;
            border-radius: 30px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.2s, transform 0.1s;
        }
        .btn:hover {
            background: #e05a00;
            transform: scale(1.02);
        }
        .btn i {
            margin-right: 0.5rem;
        }
        .rating-stars {
            display: flex;
            gap: 0.4rem;
            font-size: 1.8rem;
            color: #d0d8e4;
            cursor: pointer;
            direction: rtl;
        }
        .rating-stars input {
            display: none;
        }
        .rating-stars label {
            transition: color 0.15s;
            color: #d0d8e4;
        }
        .rating-stars label:hover,
        .rating-stars label:hover~label,
        .rating-stars input:checked~label {
            color: #ffb800;
        }
        friend-link {
            display: block;
            background: #f0f4fa;
            border-radius: 14px;
            padding: 1.4rem 2rem;
            margin: 2rem 0 1rem;
            border: 1px solid #d0d8e4;
        }
        friend-link::before {
            content: "🔗 Friend Links";
            display: block;
            font-weight: 700;
            font-size: 1.1rem;
            margin-bottom: 0.6rem;
            color: #0d1b2a;
        }
        friend-link a {
            display: inline-block;
            margin: 0.2rem 0.8rem 0.2rem 0;
            padding: 0.3rem 0.8rem;
            background: #fff;
            border-radius: 20px;
            border: 1px solid #ccd4e0;
            font-size: 0.9rem;
        }
        friend-link a:hover {
            background: #ff6b00;
            color: #fff;
            border-color: #ff6b00;
            text-decoration: none;
        }
        .site-footer {
            background: #0d1b2a;
            color: #b0c0d0;
            padding: 2.4rem 0 1.8rem;
            margin-top: 2rem;
            border-top: 4px solid #ff6b00;
        }
        .site-footer .footer-inner {
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            justify-content: space-between;
            align-items: center;
        }
        .site-footer .copy {
            font-size: 0.85rem;
        }
        .site-footer .copy strong {
            color: #e0e8f0;
        }
        @media (max-width: 768px) {
            h1 {
                font-size: 1.8rem;
            }
            h2 {
                font-size: 1.4rem;
            }
            h3 {
                font-size: 1.15rem;
            }
            .header-inner {
                flex-wrap: wrap;
            }
            .hamburger {
                display: block;
            }
            .main-nav {
                display: none;
                width: 100%;
                flex-direction: column;
                align-items: stretch;
                gap: 0.2rem;
                padding-top: 0.8rem;
                border-top: 1px solid rgba(255, 255, 255, 0.1);
                margin-top: 0.6rem;
            }
            .main-nav.open {
                display: flex;
            }
            .main-nav a {
                padding: 0.6rem 1rem;
                border-radius: 8px;
            }
            .toc ol {
                columns: 1;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .form-section {
                padding: 1.2rem 1.2rem;
            }
            .feature-image-wrap {
                margin: 1rem 0 1.6rem;
            }
            .site-footer .footer-inner {
                flex-direction: column;
                text-align: center;
            }
        }
        @media (max-width: 480px) {
            .container {
                padding: 0 0.9rem;
            }
            h1 {
                font-size: 1.5rem;
            }
            .my-logo {
                font-size: 1.4rem;
            }
            .breadcrumb {
                font-size: 0.75rem;
            }
        }
        .scroll-top {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            background: #ff6b00;
            color: #fff;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            box-shadow: 0 4px 16px rgba(255, 107, 0, 0.3);
            transition: transform 0.2s, opacity 0.2s;
            z-index: 50;
            border: none;
            cursor: pointer;
        }
        .scroll-top:hover {
            transform: scale(1.1);
            background: #e05a00;
        }
        .scroll-top.hidden {
            opacity: 0;
            pointer-events: none;
        }
        .hidden-schema {
            display: none;
        }
        .emoji-big {
            font-size: 1.8rem;
            line-height: 1;
        }
        .inline-highlight {
            background: #fff3e0;
            padding: 0.1rem 0.4rem;
            border-radius: 4px;
            font-weight: 600;
        }
        .two-col-list {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 0.2rem 1.5rem;
        }
        @media (max-width: 560px) {
            .two-col-list {
                grid-template-columns: 1fr;
            }
        }
        hr {
            border: none;
            border-top: 2px dashed #dce2ec;
            margin: 2.2rem 0;
        }