body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background-color: #222;
}

.game-container {
  position: relative;
  width: 600px;
  height: 400px;
  background-color: #000;
}



.paddle {
  position: absolute;
  width: 10px;
  height: 80px;
  background-color: #fff;
}

#player {
  left: 10px;
}

#computer {
  right: 10px;
}

.ball {
  position: absolute;
  width: 15px;
  height: 15px;
  background-color: #03fc0f;
}