body{font-family:system-ui,-apple-system,sans-serif;margin:0;padding:0;background:#fafafa;color:#222}header{padding:1rem;border-bottom:1px solid #eee;background:#fff}nav a{margin-right:1rem;text-decoration:none;color:#333;font-weight:500}main{padding:2rem;max-width:800px;margin:0 auto}h1,h2{margin-bottom:.5rem}footer{margin-top:4rem;padding:1rem;text-align:center;color:#666;font-size:.9rem}