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

#game {
  position: fixed;
  inset: 3vmin;
  display: grid;
  place-items: center;
}

#game canvas {
  display: block;
  max-width: 100vw;
  max-height: 100vh;
  box-shadow: 0 0 40px rgba(60, 255, 180, 0.18), 0 0 0 2px rgba(60, 255, 180, 0.25);
}

/* Retro CRT overlay: scanlines + vignette. Never blocks input. */
.crt {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse at center, rgba(0, 0, 0, 0) 55%, rgba(0, 0, 0, 0.45) 100%),
    repeating-linear-gradient(
      to bottom,
      rgba(0, 0, 0, 0) 0px,
      rgba(0, 0, 0, 0) 2px,
      rgba(0, 0, 0, 0.14) 3px
    );
  mix-blend-mode: multiply;
}