/* styles.css */
body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #1d2671, #c33764);
  }
  
  .calculator {
    width: 350px;
    background: #ffffff;
    border-radius: 15px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    overflow: hidden;
  }
  
  .display {
    height: 80px;
    padding: 20px;
    font-size: 2.5rem;
    font-weight: bold;
    text-align: right;
    background: #2c3e50;
    color: #ecf0f1;
    border-bottom: 1px solid #bdc3c7;
  }
  
  .buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    padding: 20px;
    background: #ecf0f1;
  }
  
  .btn {
    padding: 20px;
    font-size: 1.5rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.2s, background 0.3s;
  }
  
  .btn.number {
    background: #f0f0f0;
    color: #333;
  }
  
  .btn.operator {
    background: #3498db;
    color: white;
  }
  
  .btn.clear {
    background: #e74c3c;
    color: white;
  }
  
  .btn.equals {
    background: #27ae60;
    color: white;
    grid-column: span 1;
  }
  
  .btn:hover {
    transform: translateY(-2px);
  }
  
  .btn:active {
    transform: translateY(0);
  }
  
  .decimal {
    background: #95a5a6;
    color: white;
  }
  
  .btn.clear:hover {
    background: #c0392b;
  }
  
  .btn.equals:hover {
    background: #229954;
  }
  
  @media (max-width: 480px) {
    .calculator {
      width: 90%;
    }
    .btn {
      font-size: 1.2rem;
      padding: 15px;
    }
    .display {
      font-size: 2rem;
    }
  }