:root { color-scheme: light; }
* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: #f4f6f8;
  color: #1c2530;
}
main { max-width: 32rem; padding: 2rem 1.5rem; text-align: center; }
h1 { font-size: 2.25rem; margin: 0 0 0.75rem; color: #0b6890; }
p { line-height: 1.55; margin: 0 0 1rem; }
.button {
  display: inline-block;
  padding: 0.6rem 1.25rem;
  border-radius: 0.375rem;
  background: #0b6890;
  color: #ffffff;
  text-decoration: none;
  font-weight: 600;
}
.button:focus-visible { outline: 3px solid #1c2530; outline-offset: 2px; }
.note { font-size: 0.875rem; color: #4a5563; }