body { font-family: Arial, sans-serif; margin: 0; padding: 0; } header { background: #007bff; color: white; padding: 10px; text-align: center; } nav ul { list-style: none; padding: 0; } nav ul li { display: inline; margin-right: 15px; } nav ul li a { color: white; text-decoration: none; } main { padding: 20px; } footer { background: #f8f9fa; padding: 10px; text-align: center; } @media (max-width: 600px) { nav ul li { display: block; margin: 5px 0; } }