body {
    background-color: #f0f0f0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.calculator {
    max-width: 400px;
    width: 95%;
    margin: 20px auto;
    padding: 15px;
    border-radius: 15px;
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.2);
    background-color: #ffffff;
}

.calculator .display {
    font-size: clamp(1.5em, 4vw, 2em); /* Responsive font size */
    margin-bottom: 20px;
    text-align: right;
    padding: 15px;
    border-radius: 10px;
    background-color: #e9ecef;
    box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.1);
    cursor: text;
    overflow-x: auto; 
    white-space: nowrap;
    min-height: 60px;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 8px;
    padding: 10px;
}

.calculator button {
    width: 100%; 
    padding: 15px 5px;
    font-size: clamp(1em, 2.5vw, 1.2em); 
    border-radius: 10px;
    transition: background-color 0.3s, transform 0.3s;
    margin: 0; 
    min-height: 45px; 
}

.calculator button:hover {
    background-color: #d1d1d1;
    transform: scale(1.05);
}

/* Button colors */
.btn-secondary {
    background-color: #6c757d;
    color: #fff;
}

.btn-warning {
    background-color: #ffc107;
    color: #fff;
}

.btn-success {
    background-color: #28a745;
    color: #fff;
}

.btn-info {
    background-color: #17a2b8;
    color: #fff;
}

.btn-danger {
    background-color: #dc3545;
    color: #fff;
}

/* Media Queries for different screen sizes */
@media screen and (max-width: 480px) {
    .calculator {
        margin: 10px auto;
        padding: 10px;
    }

    .calculator button {
        padding: 10px 5px;
    }
}

@media screen and (max-width: 320px) {
    .buttons {
        gap: 5px;
    }

    .calculator button {
        padding: 8px 3px;
    }
}

/* For larger screens */
@media screen and (min-width: 768px) {
    .calculator {
        margin: 50px auto;
    }
}

/* For touch devices */
@media (hover: none) {
    .calculator button:hover {
        transform: none;
    }

    .calculator button:active {
        background-color: #d1d1d1;
        transform: scale(0.95);
    }
}

.calculator button.btn-danger {
    background-color: #dc3545;
    color: #fff;
}