body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #f4f4f4;
    font-family: Arial, sans-serif;
}

.calculator {
    background-color: #ffffff;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.3);
    width: 300px;
    padding: 20px;
}

#display {
    width: 98%;
    height: 50px;
    background-color: #e6e6e6;
    border: none;
    border-radius: 5px;
    text-align: right;
    font-size: 24px;
    margin-bottom: 10px;
}

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

button {
    height: 60px;
    background-color: #4CAF50;
    border: none;
    border-radius: 5px;
    color: white;
    font-size: 20px;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #45a049;
}

button:active {
    background-color: #3e8e41;
}

button:nth-child(4n) {
    background-color: #ff9800;
    /* Operator buttons */
}

button:nth-child(4n):hover {
    background-color: #fb8c00;
}

button:nth-child(4n):active {
    background-color: #f57c00;
}

#history {
    resize: none;
    width: 94%;
    height: 100px; /* Adjust height as needed */
    background-color: #e6e6e6;
    border: none;
    border-radius: 5px;
    margin-top: 10px;
    padding: 10px;
    font-size: 16px;
    overflow-y: auto; /* Allow scrolling if content exceeds the view */
}