:root {
  --bg: #f7f7f5;
  --fg: #1d1d1f;
  --accent: #3b6ef5;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141416;
    --fg: #ececec;
    --accent: #7c9cff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
}

main {
  max-width: 36rem;
  padding: 2rem 1rem;
  text-align: center;
}

button {
  padding: 0.6rem 1.2rem;
  border: none;
  border-radius: 0.5rem;
  background: var(--accent);
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
}

button:hover {
  filter: brightness(1.1);
}