body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; line-height: 1.6; color: #333; max-width: 1200px; margin: 0 auto; padding: 20px; }
        .mobile-nav { display: none; }
        @media (max-width: 768px) {
            .desktop-nav { display: none; }
            .mobile-nav { display: block; position: fixed; bottom: 0; width: 100%; background: #fff; padding: 10px; box-shadow: 0 -2px 10px rgba(0,0,0,0.1); }
            .nav-toggle { width: 100%; padding: 12px; background: #2c3e50; color: white; border: none; }
        }
        nav { background: #2c3e50; color: white; padding: 15px; margin-bottom: 30px; }
        nav a { color: white; text-decoration: none; margin: 0 15px; font-weight: bold; }
        .logo { font-size: 24px; font-weight: 900; letter-spacing: 1px; }
        h1 { color: #2c3e50; border-bottom: 3px solid #e74c3c; padding-bottom: 10px; }
        h2 { color: #e74c3c; margin-top: 30px; }
        h3 { color: #3498db; }
        .download-btn, .login-btn { display: inline-block; background: #27ae60; color: white; padding: 12px 25px; margin: 15px 0; text-decoration: none; border-radius: 5px; font-weight: bold; }
        .login-btn { background: #3498db; }
        img { max-width: 100%; height: auto; margin: 20px 0; border-radius: 8px; }
        .tag { background: #f1f1f1; padding: 5px 10px; border-radius: 20px; margin: 5px; display: inline-block; }
        footer { margin-top: 50px; padding: 20px; background: #2c3e50; color: white; }