*, *:after, *:before {
  box-sizing: border-box;
}

body,
button,
input[type="number"],
input[type="submit"] {
  font-size: 22px;
}

body {
  padding: 1em;
  margin: 0;
}

input[type="number"] {
  width: 4em;
}

[data-correct="true"] td {
  background: #afa;
}
[data-correct="false"] td {
  background: #faa;
}