html,
body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: #000000; /* Совпадает с letterboxColor */
}

#app {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

#pixi-container {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

canvas {
  display: block;
}