body {font-family: Arial; margin:0; background:#fff;} header {background:#0b3d91; color:white; padding:20px; text-align:center;} nav {background:black; padding:10px; text-align:center;} nav a {color:white; margin:10px; text-decoration:none;} .hero {padding:60px; text-align:center; background:#f4f4f4;} .btn {background:#0b3d91; color:white; padding:10px 20px; border:none; border-radius:5px;} .card {background:white; padding:20px; margin:10px; border-left:5px solid #0b3d91;} .whatsapp {position:fixed; bottom:20px; right:20px; background:#25D366; color:white; padding:15px; border-radius:50%; text-decoration:none;}