body{font-family:Arial,sans-serif;margin:0;background:#f4f6f9;color:#333}
header{background:#1f4e79;color:#fff;padding:24px;text-align:center}
nav a{color:#fff;margin:0 12px;text-decoration:none}
main{max-width:900px;margin:40px auto;padding:0 20px}
footer{background:#222;color:#fff;text-align:center;padding:16px;margin-top:40px}
.card{background:#fff;padding:24px;border-radius:10px;box-shadow:0 2px 8px rgba(0,0,0,.08)}