body {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background: #111;
  color: #fff;
  font-family: Arial, sans-serif;
  margin: 0;
}

canvas {
  border: 2px solid #fff;
  background: #000;
}

/* Game Over Overlay */
#gameOver {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.85);
  color: white;
  display: none;
  align-items: center;
  justify-content: center;
}

#gameOver .content {
  background: #222;
  padding: 20px 40px;
  border-radius: 12px;
  text-align: center;
}

#gameOver button {
  margin-top: 10px;
  padding: 10px 20px;
  font-size: 16px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  background: limegreen;
  color: black;
}