* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Arial, sans-serif;
  background: #111827;
  color: #e5e7eb;
  display: grid;
  place-items: center;
}

.card {
  width: min(720px, 92vw);
  padding: 36px;
  border: 1px solid #374151;
  border-radius: 18px;
  background: #1f2937;
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
}

h1 {
  margin-top: 0;
  font-size: 42px;
}

p {
  line-height: 1.7;
}

.muted {
  color: #9ca3af;
}