body {
  font-family: sans-serif;
  background: #f9f9fb;
  color: #222;
  text-align: center;
  padding: 2em;
}

.container {
  max-width: 600px;
  margin: auto;
}

.output {
  margin: 1em 0;
}

input {
  font-size: 1.2em;
  width: 250px;
  padding: 0.5em;
  margin-right: 0.5em;
}

button {
  font-size: 1em;
  padding: 0.5em 1em;
  cursor: pointer;
}

.small {
  font-size: 0.9em;
  color: #666;
}