body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f0f0f0;
    margin: 0;
}

.calculator {
    background-color: #333;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
}

.display {
    width: calc(100% - 20px);
    height: 50px;
    background-color: #eee;
    border: none;
    border-radius: 5px;
    font-size: 2em;
    text-align: right;
    padding: 10px;
    margin-bottom: 15px;
    box-sizing: border-box;
}

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

.button {
    width: 60px;
    height: 60px;
    font-size: 1.5em;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    background-color: #555;
    color: white;
    transition: background-color 0.2s ease;
}

.button:hover {
    background-color: #777;
}

.button.operator {
    background-color: #f7923b;
}

.button.operator:hover {
    background-color: #e07b27;
}

.button.clear, .button.backspace {
    background-color: #c0392b;
}

.button.clear:hover, .button.backspace:hover {
    background-color: #a52d20;
}

.button.equals {
    background-color: #27ae60;
    grid-column: span 2; /* Adjust as needed for layout */
}

.button.equals:hover {
    background-color: #1f8a4f;
}

.button.zero {
    grid-column: span 2;
}