* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
  }
  
  body {
    font-family: cursive;
    background-color: #191919;
    color: #fff;
  }
  
  h1 {
    text-align: center;
    font-size: 5rem;
    line-height: 1;
    margin-top: 45px;
  }
  
  .score {
    color: #4caf50;
    background: #302f2fed;
    padding: 1rem;
    line-height: 1;
    border-radius: 1rem;
    display: inline-block;
  }
  
  .controls {
    margin: 5px;
    text-align: center;
  }
  
  .start-btn {
    padding: 10px 25px;
    outline: none;
    font-size: 24px;
    background: #c2185b;
    color: #fff;
    border: 0px;
    box-shadow: 1px 2px 4px #c2185bb0;
    cursor: pointer;
  }
  
  .start-btn:hover {
    background: #187bc2;
    box-shadow: 1px 2px 4px #185fc2b0;
  }
  
  .levels {
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  
  /* Style for each difficulty level */
  .levels > div {
    margin: 20px;
  }
  
  .levels > div:nth-child(1) {
    color: #00ff00;
  }
  .levels > div:nth-child(2) {
    color: #ffd24e;
  }
  .levels > div:nth-child(3) {
    color: #ff0000;
  }
  
  /* Style for the game board */
  .game {
    width: 600px;
    height: 400px;
    display: flex;
    flex-wrap: wrap;
    margin: 0 auto;
  }
  
  /* Style for each hole on the game board */
  .hole {
    flex: 1 0 33.33%;
    overflow: hidden;
    position: relative;
  }
  
  /* Style for the mole inside each hole */
  .hole:after {
    background: url("img/hole.png") bottom center no-repeat;
    background-size: contain;
    content: "";
    width: 100%;
    height: 70px;
    position: absolute;
    z-index: 2;
    bottom: -30px;
  }
  
  /* Style for the mole when it pops up from a hole */
  .mole {
    position: absolute;
    top: 100%;
    width: 100%;
    height: 100%;
    background: url("img/mole.png") bottom center no-repeat;
    background-size: 60%;
    transition: all 0.4s;
    cursor: pointer;
  }
  
  /* Style for the mole when it pops up from a hole and becomes visible */
  .hole.up .mole {
    top: 0;
  }
  
  /* adjust for small screen size */
  @media (max-width: 768px) {
    h1 {
      padding: 20px;
      font-size: 2rem;
    }
  
    .score {
      margin: 20px;
    }
  
    .hole::after {
      bottom: -22px;
      margin: 6px;
    }
  
    .start-btn {
      padding: 8px 20px;
    }
  
    .levels > div {
      margin: 10px;
    }
  
    .game {
      width: 90%;
      height: 300px;
    }
  }