body { font-family: 'Arial', sans-serif; line-height: 1.6; color: #333; max-width: 1200px; margin: 0 auto; padding: 20px; }
        .mobile-nav { display: none; background: #0066cc; color: white; padding: 10px; text-align: center; cursor: pointer; }
        @media (max-width: 768px) { .desktop-nav { display: none; } .mobile-nav { display: block; } }
        nav { background: #0066cc; padding: 15px; margin-bottom: 20px; }
        nav a { color: white; text-decoration: none; margin: 0 15px; font-weight: bold; }
        h1 { color: #0066cc; border-bottom: 3px solid #ff9900; padding-bottom: 10px; }
        h2 { color: #ff9900; margin-top: 30px; }
        h3 { color: #339966; }
        .download-btn { background: #4CAF50; color: white; padding: 12px 25px; text-decoration: none; border-radius: 5px; display: inline-block; margin: 15px 0; }
        .login-btn { background: #008CBA; color: white; padding: 12px 25px; text-decoration: none; border-radius: 5px; display: inline-block; margin: 15px 10px; }
        img { max-width: 100%; height: auto; margin: 20px 0; }
        .tag { background: #f0f0f0; padding: 5px 10px; border-radius: 3px; margin: 5px; display: inline-block; }
        footer { margin-top: 40px; padding: 20px; background: #f5f5f5; }