* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: Arial, sans-serif;
  background: #f4f6f8;
}
.card {
  max-width: 620px;
  margin: 20px;
  padding: 42px;
  text-align: center;
  background: white;
  border-radius: 14px;
  box-shadow: 0 8px 30px rgba(0,0,0,.10);
}
h1 { margin-top: 0; }
.small { color: #666; }