body {
  font-family: system-ui, sans-serif;
  padding: 1rem;

  font-size: 24px;
}

h1 {
  text-align: center;
}

article {
  line-height: 1.4;
}

button {
  padding: 1rem 2rem;
  display: block;
  width: 100%;
  font-size: inherit;
}

@media only screen and (min-width: 981px) {
  body {
    font-size: 16px;
  }

  article {
    margin: 0 auto;
    max-width: 780px;
  }

  button {
    display: none;
  }
}