:root {
  --sfondo: #f6f7f9;
  --testo: #1d2430;
  --tenue: #5b6575;
  --accento: #1f6feb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --sfondo: #12161c;
    --testo: #e6e9ee;
    --tenue: #9aa4b2;
    --accento: #6aa6ff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px 16px;
  background: var(--sfondo);
  color: var(--testo);
  font: 18px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

main {
  max-width: 560px;
  text-align: center;
}

h1 {
  margin: 0 0 12px;
  font-size: 2.4rem;
}

p {
  margin: 0 0 12px;
  color: var(--tenue);
}

a {
  color: var(--accento);
}