body{font-family:Arial;margin:0} header{background:#0a3d62;color:#fff;padding:15px} nav a{color:#fff;margin:10px;text-decoration:none} .hero{background:#ccc;padding:80px;text-align:center} .section{padding:30px} .card{border:1px solid #ddd;padding:15px;margin:10px} footer{background:#222;color:#fff;text-align:center;padding:20px}