body {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f0f0;
  }
  
  .calculator {
    border: 2px solid #ccc;
    border-radius: 8px;
    overflow: hidden;
    width: 300px;
    background-color: #fff;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  }
  
  .display {
    width: 100%;
    padding: 10px;
    font-size: 1.5em;
    border: none;
    outline: none;
  }
  
  .buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
  }
  
  button {
    border: none;
    outline: none;
    font-size: 1.2em;
    padding: 15px;
    cursor: pointer;
    background-color: #e0e0e0;
    transition: background-color 0.3s;
  }
  
  button:hover {
    background-color: #d0d0d0;
  }
  
  .operator {
    color: #fff;
    background-color: #ff9500;
  }
  
  .equal {
    color: #fff;
    background-color: #28a745;
  }
  
  .clear {
    color: #fff;
    background-color: #dc3545;
  }
  
  .dot {
    grid-column: span 2;
  }