* { margin: 0; padding: 0; box-sizing: border-box; }
        html { scroll-behavior: smooth; }
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
            line-height: 1.7;
            color: #333;
            background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
            min-height: 100vh;
        }
        img { max-width: 100%; height: auto; display: block; }
        h1, h2, h3, h4 { font-weight: 800; line-height: 1.3; margin-bottom: 1rem; color: #1a365d; }
        h1 { font-size: clamp(2.5rem, 5vw, 3.5rem); text-align: center; margin-top: 1.5rem; }
        h2 { font-size: clamp(1.8rem, 4vw, 2.5rem); border-left: 5px solid #2b6cb0; padding-left: 1rem; margin-top: 2.5rem; }
        h3 { font-size: clamp(1.5rem, 3vw, 1.9rem); color: #2d3748; margin-top: 2rem; }
        h4 { font-size: 1.3rem; color: #4a5568; margin-top: 1.5rem; }
        p { margin-bottom: 1.5rem; font-size: 1.1rem; }
        .lead { font-size: 1.3rem; font-weight: 500; color: #4a5568; margin-bottom: 2rem; }
        .highlight { background-color: #fffacd; padding: 0.2rem 0.5rem; border-radius: 3px; font-weight: 600; }
        strong { color: #2b6cb0; }
        em { color: #718096; }
        .emoji { font-size: 1.2em; margin-right: 0.3rem; }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background: linear-gradient(90deg, #1a365d 0%, #2b6cb0 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-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo {
            font-size: 2rem;
            font-weight: 900;
            text-decoration: none;
            color: white;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .my-logo i { color: #f6ad55; }
        .my-logo:hover { color: #f6ad55; }
        nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
        }
        nav a {
            color: white;
            text-decoration: none;
            font-weight: 600;
            font-size: 1.1rem;
            padding: 0.5rem 0;
            transition: color 0.3s;
            position: relative;
        }
        nav a:hover { color: #f6ad55; }
        nav a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 3px;
            background: #f6ad55;
            transition: width 0.3s;
        }
        nav a:hover::after { width: 100%; }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.8rem;
            cursor: pointer;
        }
        @media (max-width: 768px) {
            nav ul {
                flex-direction: column;
                position: fixed;
                top: 70px;
                right: -100%;
                background: #1a365d;
                width: 80%;
                height: calc(100vh - 70px);
                padding: 2rem;
                transition: right 0.5s ease;
                box-shadow: -5px 0 15px rgba(0,0,0,0.2);
            }
            nav ul.active { right: 0; }
            .hamburger { display: block; }
        }
        .breadcrumb {
            padding: 1rem 0;
            font-size: 0.9rem;
            color: #718096;
        }
        .breadcrumb a {
            color: #2b6cb0;
            text-decoration: none;
        }
        .breadcrumb a:hover { text-decoration: underline; }
        main {
            background: white;
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0,0,0,0.08);
            padding: 2.5rem;
            margin: 2rem auto;
        }
        .content-section {
            margin-bottom: 3rem;
        }
        .interactive-box {
            background: #f7fafc;
            border: 2px solid #e2e8f0;
            border-radius: 10px;
            padding: 2rem;
            margin: 2rem 0;
        }
        .form-group {
            margin-bottom: 1.5rem;
        }
        label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 600;
        }
        input, textarea, select {
            width: 100%;
            padding: 0.8rem;
            border: 1px solid #cbd5e0;
            border-radius: 8px;
            font-size: 1rem;
            transition: border 0.3s;
        }
        input:focus, textarea:focus, select:focus {
            outline: none;
            border-color: #2b6cb0;
            box-shadow: 0 0 0 3px rgba(43, 108, 176, 0.2);
        }
        button {
            background: linear-gradient(90deg, #2b6cb0, #1a365d);
            color: white;
            border: none;
            padding: 0.9rem 2rem;
            border-radius: 8px;
            font-weight: 700;
            cursor: pointer;
            transition: transform 0.3s, box-shadow 0.3s;
        }
        button:hover {
            transform: translateY(-3px);
            box-shadow: 0 7px 14px rgba(43, 108, 176, 0.3);
        }
        .article-image {
            border-radius: 12px;
            overflow: hidden;
            margin: 2.5rem auto;
            box-shadow: 0 10px 20px rgba(0,0,0,0.1);
            max-width: 800px;
        }
        .img-caption {
            text-align: center;
            font-style: italic;
            color: #718096;
            margin-top: 0.5rem;
            font-size: 0.95rem;
        }
        .internal-links {
            background: #edf2f7;
            padding: 1.5rem;
            border-radius: 10px;
            margin: 2rem 0;
        }
        .internal-links ul {
            list-style: none;
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 1rem;
        }
        .internal-links a {
            color: #2b6cb0;
            text-decoration: none;
            display: block;
            padding: 0.7rem;
            border-radius: 6px;
            transition: background 0.3s;
        }
        .internal-links a:hover {
            background: #e2e8f0;
            text-decoration: underline;
        }
        footer {
            background: #1a365d;
            color: white;
            padding: 3rem 0 1.5rem;
            margin-top: 3rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2rem;
            margin-bottom: 2rem;
        }
        .footer-section h3 { color: #f6ad55; border-left: none; padding-left: 0; }
        .footer-section a { color: #cbd5e0; text-decoration: none; }
        .footer-section a:hover { color: #f6ad55; }
        friend-link {
            display: block;
            margin: 0.5rem 0;
            font-weight: 600;
        }
        .copyright {
            text-align: center;
            padding-top: 1.5rem;
            border-top: 1px solid #2d3748;
            font-size: 0.9rem;
            color: #a0aec0;
        }
        @media (max-width: 768px) {
            main { padding: 1.5rem; }
            h2 { font-size: 1.6rem; }
            .internal-links ul { grid-template-columns: 1fr; }
        }