body {
    background-color: bisque;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center
}

.calculator {
    box-shadow: 0 0 25px 7px green;
    background-color: black;
    padding: 50px;
    width: 500px;
    border-radius: 28px;
}

.display {
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    margin-bottom: 50px;
    background-color: azure;
    padding: 7px;
}

.input {
    font-size: 2rem;
    color: black;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.btn {
    border: none;
    border-radius: 10px;
    padding: 25px 0;
    font-size: 2.5rem;
    background-color: black;
    color: beige;
    box-shadow: 0 0 10px 2px green;

}

.btn:hover {
    opacity: .6;
    color: orange;
}

.op {
    color: aqua;
}

.zero {
    grid-column: span 2;
}

.equals {
    grid-column: span 2;
}

/* Media query for screens smaller than 700px */
@media only screen and (max-width: 700px) {
    .calculator {
      padding: 25px;
      width: 230px;
    }
  
    .display {
      height: 30px;
      margin-bottom: 25px;
      font-size: 1em;
    }
  
    .input {
        font-size: 1rem;
    }

    .buttons {
      gap: 12px;
    }
  
    .btn {
      padding: 12px 0;
      font-size: 1.25em;
      box-shadow: 0 0 5px 1px green;
    }
  }