index.css

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

body {
  font-family: sans-serif;
  width: 100vw;
  height: 100vh;
  padding: 10px;
  display: grid;
  grid-template-columns: auto 2fr 1fr;
  grid-template-rows: auto 1fr;
  grid-template-areas:
    "nav      nav    nav"
    "controls canvas instructions";
}

@media (max-aspect-ratio: 3/2) {
  body {
    grid-template-columns: auto 1fr;
    grid-template-rows: auto 1fr 20em;
    grid-template-areas:
      "nav          nav"
      "controls     canvas"
      "instructions instructions";
  }
}

nav {
  grid-area: nav;
  margin-bottom: 6px;
  display: flex;
  gap: 6px;
}

nav a {
  padding: 1px 10px;
  background-color: green;
  text-decoration: none;
  font-size: 24px;
  color: white;
}

#controls {
  grid-area: controls;
  padding: 10px;
  display: flex;
  flex-direction: column;
  justify-content: safe center;
  align-items: center;
  text-align: center;
  gap: 1.3em;
  overflow: scroll;
}

button,
input {
  font-size: 1em;
  padding: 2px 5px;
}

#canvas {
  grid-area: canvas;
  width: 100%;
  height: 100%;
}

#instructions {
  grid-area: instructions;
  padding: 10px;
  overflow: scroll;
}

#instructions p,
#instructions h2 {
  margin-bottom: 1em;
}

#controls,
#canvas,
#instructions {
  border: solid black 1px;
}