/* General Body Styles */
body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background: #f3f3f3;
}

.calculator {
    background: #fff;
    border-radius: 10px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.1);
    width: 300px;
    overflow: hidden;
    position: relative;
}

.display {
    background: #222;
    color: #fff;
    font-size: 2rem;
    padding: 20px;
    text-align: right;
    border-bottom: 1px solid #ccc;
    height: 70px;
}

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

button {
    font-size: 1.2rem;
    padding: 20px;
    background: #fff;
    border: none;
    outline: none;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background: #f0f0f0;
}

/* Equal Button */
button.equal {
    background: #007BFF;
    color: white;
}

button.equal:hover {
    background: #0056b3;
}

/* Zero Button */
button.zero {
    background: #fff; /* Zero button is white */
}

/* Branding Styles */
.branding {
    background: #ccc;
    color: #555;
    font-size: 0.9rem;
    font-weight: bold;
    text-align: center;
    padding: 10px;
    grid-column: span 2; /* Spans across the last two cells (3rd and 4th columns) */
    display: flex;
    justify-content: space-between;
    align-items: center;
}