* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  color-scheme: light dark;
  font-size: clamp(1rem, 0.861rem + 0.696vw, 1.2rem);
}

/* TODO: https://w3.org/TR/css-overflow-3/#text-overflow */
table {
  height: 100dvh;
  width: 100dvw;
}

td {
  word-wrap: break-word;
  vertical-align: top;
  overflow-y: scroll;
}

.block-x,
.block-y {
  text-align: center;
  vertical-align: middle;
}

button {
  padding: 1em 3em;
}

.block-1,
.block-7 {
  background: blue;
}

.block-2,
.block-4 {
  background: orange;
}

.block-3,
.block-6 {
  background: green;
}

thead,
tfoot {
  height: 15%;
}

.block-3 {
  height: 30%;
}

/* TODO: block-6 */