body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, sans-serif;
  background: #111;
  color: #fff;
  display: flex;
  justify-content: center;
  padding: 40px;
}

main {
  max-width: 600px;
  width: 100%;
}

input,
button {
  padding: 10px;
  margin-top: 10px;
}