* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  }
  :root {
    --layout: #F4EEE0;
    --background-color: #4F4557;
    --box-shadow: -8px -8px -15px rgb(255, 253, 253) 5px 5px 15px rgb(240, 238, 238);
    --hover-color: #6D5D6E;
  }
  .container {
    width: 100%;
    height: 100vh;
    background: var(--layout);
    display: flex;
    align-items: center;
    justify-content: center;
  }
  .calculator {
    background: var(--background-color);
    padding: 20px;
    border-radius: 5px;
  }
  .calculator form input {
    border: 0;
    outline: 0;
    width: 60px;
    height: 60px;
    border-radius: 10px 10px;
    box-shadow: -8px -8px 15px rgba(87, 86, 86, 0.59), 5px 5px 15px rgb(193, 193, 193);

    background: transparent;
    font-size: 25px;
    cursor: pointer;
    margin: 10px;
    color: var(--layout);
  }
  .calculator form input:hover {
    background-color: var(--hover-color);
  }
  form .display {
    display: flex;
    justify-content: flex-end;
    margin: 20px 0;
  }
  form .display input {
    text-align: right;
    flex: 1;
    font-size: 45px;
    box-shadow: none;
  }
  form input.equal {
    width: 150px;
  }
  
  /* LET'S ADD THE MEDIA QUARRIES */
  @media (max-width: 768px) {
    .calculator form input {
      width: 40px;
      height: 40px;
      font-size: 16px;
    }
    form .display input {
      font-size: 30px;
    }
    form input.equal {
      width: 120px;
    }
  }
  
  @media (max-width: 480px) {
    .calculator form input {
      width: 30px;
      height: 30px;
      font-size: 12px;
    }
    form .display input {
      font-size: 20px;
    }
    form input.equal {
      width: 100px;
    }
  }