body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: linear-gradient(135deg, #74ebd5 0%, #acb6e5 100%);
  font-family: 'Arial', sans-serif;
}

.calculator {
  background: rgba(255, 255, 255, 0.9);
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
  width: 300px; /* Set a fixed width for the calculator */
}

.calculator-display {
  width: 100%;
  padding: 15px 0;
  font-size: 1.5rem;
  text-align: right;
  border: none;
  margin-bottom: 10px;
  border-radius: 5px;
  box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.1);
  background: linear-gradient(90deg, #f0e130, #ffab00); /* Gradient background for the display */
  color: #fff; /* Text color */
  overflow: hidden; /* Prevent overflow */
}

.calculator-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.btn {
  padding: 15px;
  font-size: 1.2rem;
  border: none;
  border-radius: 5px;
  background-color: #ffffff; /* White button background */
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  cursor: pointer;
  transition: background-color 0.2s, transform 0.2s; /* Added transform transition */
}

.btn:hover {
  background-color: #e0e0e0; /* Slightly darker on hover */
  transform: scale(1.05); /* Scale up on hover */
}

.operator {
  background-color: #ffab00; /* Operator button color */
  color: #fff;
}

.operator:hover {
  background-color: #ff9100; /* Darker operator button on hover */
}

.equal {
  grid-column: span 4; /* Span across all columns */
  background-color: #4caf50; /* Equal button color */
  color: #fff;
}

.equal:hover {
  background-color: #45a049; /* Darker equal button on hover */
}