cat > style.css <<'CSS'
body {
  font-family: Arial, Helvetica, sans-serif;
  margin: 0; padding: 0;
  display: flex; align-items: center; justify-content: center;
  height: 100vh; background: #f5f8fb;
}
main { text-align: center; }
h1 { color: #0b5cff; margin: 0 0 8px 0; }
p { margin: 0 0 12px 0; }
a { color: #0b5cff; text-decoration: none; font-weight: 600; }
CSS