/* ── custom properties ── */

:root {
  --style-bg-color: #000000;
  --style-text-color: #ffffff;
}

/* ── reset ── */

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

/* ── page layout ── */

html,
body {
  display: flex;
  width: 100%;
  height: 100%;
  justify-content: center;
  align-items: center;
  background: var(--style-bg-color);
  overflow: hidden;
  font-family: 'Courier New', monospace;
  color: var(--style-text-color);
}

/* ── game canvas container ── */

#game-container {
  display: block;
  width: 480px;
  height: 720px;
}

#game-container canvas {
  display: block;
}