* {
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}

#calculator {
    width: 400px;
    height: 570px;
    margin: 100px auto;
    background-color: #797373;
    color: #fff;
    border-radius: 10px;
    border-radius: 20px;
    box-shadow: 10px 10px 15px .1px black;
}


.display {
    width: 100%;
    height: 80px;
    background-color: #4e5a49;
    font-size: 36px;
    text-align: right;
    padding: 20px;
    box-sizing: border-box;
    border-top-right-radius: 20px;
    border-top-left-radius: 20px;
    font-weight: bolder;
    font-family: cursive;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-gap: 20px;
    padding: 20px;
}


button {
      width: 100%;
      height: 70px;
      font-size: 24px;
      background-color: #fff;
      color: #333;
      border-radius: 5px;
      border: none;
      cursor: pointer;
      font-weight: bolder;
}

.operator {
    background-color: #f39c12;
    color: #fff;
}

button:hover{
    transform: scale(1.05);
  }