body { font-family: Arial, sans-serif; padding: 10px; background: #f4f4f4; }
.btn { display: block; margin: 10px 0; padding: 10px; background: #005bbb; color: white; text-align: center; text-decoration: none; }
h1 { margin: 0; }
header { background: #005bbb; color: white; padding: 10px; text-align: center; }