html,
body {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100%;
  display: grid;
  place-items: center;
  background: #111;
  color: white;
  font-family: Courier, monospace;
}

main {
  box-sizing: border-box;
  width: min(640px, 100%);
  max-height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 16px;
}

p {
  margin: 0;
  font-size: 14px;
  text-align: center;
}

.controls {
  display: flex;
  gap: 12px;
}

button {
  font-family: inherit;
  font-size: 14px;
  color: white;
  background: #222;
  border: 1px solid #555;
  padding: 8px 16px;
  cursor: pointer;
}

button:disabled {
  opacity: 0.45;
  cursor: default;
}

button:not(:disabled):hover {
  background: #333;
}

canvas {
  width: min(600px, 100%, calc(100vh - 132px));
  height: auto;
  aspect-ratio: 1;
  background: black;
  display: block;
}

canvas:focus {
  outline: 2px solid #555;
}