body { font-family: Arial, sans-serif; margin: 0; padding: 0; background: #fafafa; color: #222; }
header { background: #fff; padding: 20px; text-align: center; border-bottom: 1px solid #eee; }
nav a { margin: 0 10px; text-decoration: none; color: #444; }
section { padding: 20px; max-width: 800px; margin: auto; }