* { margin: 0; padding: 0; box-sizing: border-box; }
        html { scroll-behavior: smooth; }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.7;
            color: #333;
            background-color: #f8f9fa;
            max-width: 100vw;
            overflow-x: hidden;
        }
        .container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        .site-header {
            background: linear-gradient(135deg, #1a237e 0%, #283593 100%);
            color: white;
            padding: 1rem 0;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo {
            font-family: 'Georgia', serif;
            font-size: 2.2rem;
            font-weight: 800;
            text-decoration: none;
            color: #FFD700;
            letter-spacing: 1px;
            display: flex;
            align-items: center;
        }
        .my-logo i { margin-right: 10px; }
        .my-logo span { color: white; }
        .main-nav { display: flex; }
        .nav-links {
            display: flex;
            list-style: none;
            gap: 1.8rem;
        }
        .nav-links a {
            color: #e0e0e0;
            text-decoration: none;
            font-weight: 600;
            font-size: 1rem;
            padding: 8px 5px;
            border-bottom: 2px solid transparent;
            transition: all 0.3s ease;
        }
        .nav-links a:hover, .nav-links a.active {
            color: #FFD700;
            border-bottom-color: #FFD700;
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            cursor: pointer;
            color: white;
        }
        .breadcrumb {
            background: #e8eaf6;
            padding: 12px 0;
            font-size: 0.9rem;
            margin-bottom: 2rem;
        }
        .breadcrumb a {
            color: #3949ab;
            text-decoration: none;
        }
        .breadcrumb a:hover { text-decoration: underline; }
        .breadcrumb span { color: #757575; }
        main { background: white; padding: 2.5rem 0; border-radius: 8px; box-shadow: 0 5px 15px rgba(0,0,0,0.05); margin-bottom: 3rem; }
        .article-header { text-align: center; margin-bottom: 3rem; padding-bottom: 2rem; border-bottom: 1px solid #eee; }
        h1 { font-size: 2.8rem; color: #1a237e; margin-bottom: 1rem; line-height: 1.2; }
        .article-meta { color: #666; font-size: 0.95rem; margin-bottom: 1.5rem; }
        .article-meta i { margin-right: 5px; color: #3949ab; }
        .lead {
            font-size: 1.3rem;
            color: #555;
            max-width: 800px;
            margin: 0 auto 2rem;
            line-height: 1.6;
        }
        .content-area { padding: 0 2rem; }
        h2 { font-size: 2rem; color: #283593; margin: 2.5rem 0 1.2rem; padding-bottom: 0.5rem; border-bottom: 2px solid #c5cae9; }
        h3 { font-size: 1.6rem; color: #3949ab; margin: 2rem 0 1rem; }
        h4 { font-size: 1.3rem; color: #5c6bc0; margin: 1.8rem 0 0.8rem; }
        p { margin-bottom: 1.5rem; font-size: 1.05rem; text-align: justify; }
        .highlight { background: #f3e5f5; padding: 1.5rem; border-left: 4px solid #7b1fa2; margin: 1.8rem 0; border-radius: 0 8px 8px 0; }
        .highlight strong { color: #7b1fa2; }
        .stats-box {
            background: linear-gradient(to right, #e3f2fd, #f3e5f5);
            padding: 2rem;
            border-radius: 10px;
            margin: 2.5rem 0;
            border: 1px solid #bbdefb;
        }
        .stats-box h3 { margin-top: 0; }
        ul, ol { margin-left: 2rem; margin-bottom: 1.5rem; }
        li { margin-bottom: 0.7rem; }
        a { color: #1a237e; text-decoration: none; transition: color 0.3s; }
        a:hover { color: #ff9800; text-decoration: underline; }
        .internal-link { font-weight: 600; color: #3949ab; }
        .internal-link:hover { color: #ff5722; }
        img.responsive-img {
            max-width: 100%;
            height: auto;
            display: block;
            margin: 2rem auto;
            border-radius: 8px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
            border: 1px solid #ddd;
        }
        .img-caption {
            text-align: center;
            font-style: italic;
            color: #666;
            margin-top: -1rem;
            margin-bottom: 2rem;
            font-size: 0.95rem;
        }
        blockquote {
            border-left: 5px solid #FFD700;
            padding-left: 1.5rem;
            margin: 2rem 0;
            font-style: italic;
            color: #555;
            background: #fffde7;
            padding-top: 1rem;
            padding-bottom: 1rem;
            border-radius: 0 5px 5px 0;
        }
        .emoji { font-size: 1.2em; margin-right: 5px; }
        .keyword { background-color: #e8f5e9; padding: 2px 6px; border-radius: 3px; font-weight: bold; color: #2e7d32; }
        .tooltip { position: relative; display: inline-block; border-bottom: 1px dotted #3949ab; cursor: help; }
        .tooltip .tooltiptext {
            visibility: hidden;
            width: 200px;
            background-color: #3949ab;
            color: #fff;
            text-align: center;
            border-radius: 6px;
            padding: 8px;
            position: absolute;
            z-index: 1;
            bottom: 125%;
            left: 50%;
            margin-left: -100px;
            opacity: 0;
            transition: opacity 0.3s;
            font-size: 0.9rem;
        }
        .tooltip:hover .tooltiptext { visibility: visible; opacity: 1; }
        .feature-section { margin: 3rem 0; }
        .feature-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin-top: 1.5rem;
        }
        .feature-card {
            background: white;
            border: 1px solid #e0e0e0;
            border-radius: 10px;
            padding: 1.8rem;
            box-shadow: 0 4px 8px rgba(0,0,0,0.05);
            transition: transform 0.3s, box-shadow 0.3s;
        }
        .feature-card:hover { transform: translateY(-5px); box-shadow: 0 8px 16px rgba(0,0,0,0.1); }
        .feature-card h4 { color: #1a237e; }
        .feature-card i { font-size: 2rem; color: #3949ab; margin-bottom: 1rem; }
        .interactive-forms { background: #f5f5f5; padding: 2.5rem; border-radius: 10px; margin: 3rem 0; }
        .form-group { margin-bottom: 1.5rem; }
        .form-group label { display: block; margin-bottom: 0.5rem; font-weight: 600; color: #333; }
        .form-control {
            width: 100%;
            padding: 12px 15px;
            border: 1px solid #ccc;
            border-radius: 6px;
            font-size: 1rem;
            transition: border 0.3s;
        }
        .form-control:focus { border-color: #3949ab; outline: none; box-shadow: 0 0 0 3px rgba(57, 73, 171, 0.2); }
        .btn {
            background: linear-gradient(to right, #1a237e, #3949ab);
            color: white;
            border: none;
            padding: 12px 24px;
            border-radius: 6px;
            cursor: pointer;
            font-size: 1rem;
            font-weight: 600;
            transition: background 0.3s, transform 0.2s;
        }
        .btn:hover { background: linear-gradient(to right, #283593, #5c6bc0); transform: scale(1.02); }
        .rating-stars { display: flex; gap: 5px; margin: 1rem 0; }
        .rating-stars input { display: none; }
        .rating-stars label { font-size: 1.8rem; color: #ddd; cursor: pointer; transition: color 0.2s; }
        .rating-stars input:checked ~ label, .rating-stars label:hover, .rating-stars label:hover ~ label { color: #FFD700; }
        .site-footer {
            background: #1a237e;
            color: #e0e0e0;
            padding: 3rem 0 1.5rem;
            margin-top: 4rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2.5rem;
            margin-bottom: 2.5rem;
        }
        .footer-section h3 { color: #FFD700; margin-bottom: 1.5rem; font-size: 1.3rem; }
        .footer-links { list-style: none; }
        .footer-links li { margin-bottom: 0.8rem; }
        .footer-links a { color: #bbdefb; text-decoration: none; }
        .footer-links a:hover { color: #FFD700; }
        friend-link {
            display: block;
            background: #283593;
            padding: 1.5rem;
            border-radius: 8px;
            margin-top: 1rem;
        }
        friend-link a { color: #FFD700; font-weight: bold; }
        .copyright {
            text-align: center;
            padding-top: 1.5rem;
            border-top: 1px solid #3949ab;
            font-size: 0.9rem;
            color: #90a4ae;
        }
        @media (max-width: 992px) {
            h1 { font-size: 2.4rem; }
            .content-area { padding: 0 1rem; }
        }
        @media (max-width: 768px) {
            .hamburger { display: block; }
            .main-nav { position: relative; }
            .nav-links {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 100%;
                right: 0;
                background: #1a237e;
                width: 250px;
                padding: 1rem;
                border-radius: 0 0 8px 8px;
                box-shadow: 0 10px 20px rgba(0,0,0,0.2);
                z-index: 1001;
            }
            .nav-links.active { display: flex; }
            .nav-links li { margin: 0.5rem 0; }
            .header-container { flex-wrap: wrap; }
            .my-logo { font-size: 1.8rem; }
            .feature-grid { grid-template-columns: 1fr; }
            .interactive-forms { padding: 1.5rem; }
        }
        @media (max-width: 480px) {
            h1 { font-size: 2rem; }
            h2 { font-size: 1.7rem; }
            h3 { font-size: 1.4rem; }
            .lead { font-size: 1.1rem; }
            .article-meta { font-size: 0.85rem; }
        }