body {
  margin: 0;
  background-color: #f4f4f4;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  font-family: Arial, sans-serif;
}

#game {
  position: relative;
  width: 800px;
  height: 300px;
  background-color: #e0e0e0;
  overflow: hidden;
  border: 2px solid #333;
  border-radius: 10px;
}

#player {
  position: absolute;
  width: 50px;
  height: 50px;
  background-color: #4caf50;
  bottom: 0;
  left: 50px;
  border-radius: 5px;
}

#obstacle {
  position: absolute;
  width: 40px;
  height: 60px;
  background-color: #f44336;
  bottom: 0;
  right: -50px;
  border-radius: 5px;
  animation: moveObstacle 2s linear infinite;
}

@keyframes moveObstacle {
  from {
    right: -50px;
  }
  to {
    right: 850px;
  }
}

.jump {
  animation: jump 0.5s ease-out;
}

@keyframes jump {
  0%   { bottom: 0; }
  50%  { bottom: 120px; }
  100% { bottom: 0; }
}

#score {
  position: absolute;
  top: 10px;
  left: 10px;
  font-size: 20px;
  font-weight: bold;
  color: #333;
}