* { 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: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
            min-height: 100vh;
        }
        a { color: #1a73e8; text-decoration: none; transition: color 0.3s ease; }
        a:hover { color: #d32f2f; }
        img { max-width: 100%; height: auto; display: block; }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        .site-header {
            background: rgba(25, 35, 70, 0.95);
            color: white;
            padding: 1rem 0;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }
        .header-inner {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo a {
            font-size: 2.2rem;
            font-weight: 800;
            color: #ffcc00;
            text-decoration: none;
            font-family: 'Arial Black', sans-serif;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
        }
        .logo a:hover { color: #fff; }
        .nav-desktop {
            display: flex;
            gap: 2rem;
        }
        @media (max-width: 768px) {
            .nav-desktop { display: none; }
        }
        .nav-desktop a {
            color: #e0e0ff;
            font-weight: 600;
            padding: 0.5rem 0;
            border-bottom: 2px solid transparent;
        }
        .nav-desktop a:hover {
            color: #ffcc00;
            border-bottom-color: #ffcc00;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.8rem;
            cursor: pointer;
        }
        @media (max-width: 768px) {
            .hamburger { display: block; }
        }
        .nav-mobile {
            display: none;
            flex-direction: column;
            background: rgba(25, 35, 70, 0.98);
            padding: 1rem;
            position: absolute;
            top: 100%;
            left: 0;
            width: 100%;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }
        .nav-mobile.active { display: flex; }
        .nav-mobile a {
            color: #e0e0ff;
            padding: 0.8rem;
            border-bottom: 1px solid #444;
        }
        .nav-mobile a:hover { background: #2a3a7a; color: #ffcc00; }
        .breadcrumb {
            padding: 1rem 0;
            font-size: 0.9rem;
            color: #666;
        }
        .breadcrumb a { color: #555; }
        .breadcrumb a:hover { color: #1a73e8; }
        .breadcrumb span { color: #888; }
        .main-content {
            background: white;
            border-radius: 12px;
            padding: 2.5rem;
            margin: 2rem auto;
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.08);
        }
        h1 {
            font-size: 2.8rem;
            color: #1a237e;
            margin-bottom: 1.5rem;
            border-bottom: 3px solid #ffcc00;
            padding-bottom: 0.5rem;
        }
        h2 {
            font-size: 2rem;
            color: #283593;
            margin: 2rem 0 1rem;
            padding-left: 0.5rem;
            border-left: 5px solid #d32f2f;
        }
        h3 {
            font-size: 1.5rem;
            color: #3949ab;
            margin: 1.5rem 0 0.8rem;
        }
        p {
            margin-bottom: 1.2rem;
            text-align: justify;
        }
        .highlight {
            background: #e3f2fd;
            padding: 1.5rem;
            border-left: 5px solid #2196f3;
            margin: 1.5rem 0;
            border-radius: 0 8px 8px 0;
        }
        .emoji { font-size: 1.2rem; margin-right: 0.3rem; }
        .bold { font-weight: 800; color: #1a237e; }
        .img-container {
            text-align: center;
            margin: 2rem 0;
            padding: 1rem;
            background: #f8f9fa;
            border-radius: 10px;
        }
        .img-container img {
            border-radius: 8px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
            margin: 0 auto;
        }
        .caption {
            font-style: italic;
            color: #666;
            margin-top: 0.5rem;
        }
        .tier-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 1.5rem;
            margin: 2rem 0;
        }
        .tier-card {
            background: #fff;
            border: 1px solid #ddd;
            border-radius: 10px;
            padding: 1.5rem;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            text-align: center;
        }
        .tier-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.1);
        }
        .tier-s { border-top: 6px solid #ff9800; }
        .tier-a { border-top: 6px solid #4caf50; }
        .tier-b { border-top: 6px solid #2196f3; }
        .tier-c { border-top: 6px solid #9c27b0; }
        .interaction-section {
            margin: 3rem 0;
            padding: 2rem;
            background: #f1f8ff;
            border-radius: 12px;
        }
        .form-group {
            margin-bottom: 1.5rem;
        }
        label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 600;
            color: #333;
        }
        input, textarea, select {
            width: 100%;
            padding: 0.8rem;
            border: 1px solid #ccc;
            border-radius: 6px;
            font-size: 1rem;
        }
        button {
            background: linear-gradient(to right, #1a73e8, #4a90e2);
            color: white;
            border: none;
            padding: 0.8rem 1.8rem;
            border-radius: 6px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.3s ease, transform 0.2s;
        }
        button:hover {
            background: linear-gradient(to right, #0d5bb5, #2a75d8);
            transform: scale(1.03);
        }
        .rating-stars {
            display: flex;
            gap: 0.5rem;
            margin: 1rem 0;
        }
        .star {
            font-size: 1.8rem;
            color: #ddd;
            cursor: pointer;
            transition: color 0.2s;
        }
        .star.active, .star:hover { color: #ffcc00; }
        .footer-links {
            background: #2d3748;
            color: #cbd5e0;
            padding: 2rem 0;
            margin-top: 3rem;
        }
        .web-links-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 1rem;
            margin-bottom: 2rem;
        }
        .web-link {
            background: #4a5568;
            padding: 1rem;
            border-radius: 6px;
            transition: background 0.3s;
        }
        .web-link:hover { background: #5a6578; }
        .web-link a { color: #90cdf4; }
        .web-link a:hover { color: white; }
        .copyright {
            text-align: center;
            padding: 1.5rem;
            background: #1a202c;
            color: #a0aec0;
            font-size: 0.9rem;
        }
        @media (max-width: 768px) {
            h1 { font-size: 2.2rem; }
            h2 { font-size: 1.7rem; }
            .main-content { padding: 1.5rem; }
            .tier-grid { grid-template-columns: 1fr; }
            .header-inner { padding: 0 1rem; }
        }