:root {
  --primary-color: #1a73e8;
  --secondary-color: #fbbc05;
}
body { font-family: Arial, sans-serif; margin:0; padding:0; background:#f5f5f5; }
header { background: var(--primary-color); color:white; padding: 1rem; text-align:center; }
a { color: var(--primary-color); text-decoration:none; }
button { background: var(--secondary-color); border:none; padding:10px 20px; cursor:pointer; color:#000; border-radius:5px; }