* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  .obstacle {
    position: absolute;
    bottom: 0;
  }
  
  .greenObstacle {
    background-color: green;
  }
  
  .redObstacle {
    background-color: red;
  }
  body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #f0f0f0;
  }
  
  #gameArea {
    position: relative;
    width: 800px;
    height: 400px;
    background-color:rgb(198, 228, 239); 
    overflow: hidden;
    border: 2px solid #000;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  }
  
  #runner {
    position: absolute;
    bottom: 20px;
    left: 50px;
    width: 20px;
    height: 30px;
    background-color: #FF6347; 
  }
  
  #obstacle {
    position: absolute;
    bottom: 20px;
    right: -50px;
    width: 10px;
    height: 8ch;
    background-color: #32CD32;
    animation: moveObstacle 3s linear infinite;
  }
  
  #scoreDisplay {
    position: absolute;
    top: 10px;
    left: 10px;
    font-size: 54px;
    color: #000;
  }
  
  @keyframes moveObstacle {
    0% {
      right: -50px;
    }
    100% {
      right: 800px; 
    }
  }