html, body {
  margin: 0;
  height: 100%;
  background: #000;
  overflow: hidden;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
}

#screen {
  position: relative;
  width: min(100vw, calc(100vh * 4 / 3));
  height: min(100vh, calc(100vw * 3 / 4));
  background: #000;
}

#game {
  display: block;
  width: 100%;
  height: 100%;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  cursor: none;
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
  -webkit-tap-highlight-color: transparent;
}

/* Optional CRT look (toggle with C): scanlines + soft vignette. */
#screen.crt::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    repeating-linear-gradient(to bottom, rgba(0, 0, 0, 0.22) 0, rgba(0, 0, 0, 0.22) 1px, transparent 1px, transparent 3px),
    radial-gradient(ellipse at center, transparent 60%, rgba(0, 0, 0, 0.45) 100%);
}