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

html, body {
  width: 100%;
  height: 100%;
  /* dvh = dynamic viewport height — shrinks when iOS URL bar is visible.
     Supported in modern mobile browsers; falls back to 100% elsewhere. */
  height: 100dvh;
  overflow: hidden;
  background: #000;
  touch-action: none;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  user-select: none;
}

/* Center the canvas — on desktop the playfield stays phone-shaped and
   bounded to the ship's reachable area, black around everything else. */
body {
  display: flex;
  justify-content: center;
  align-items: center;
}

canvas {
  display: block;
}