body {
    font-family: 'Arial', sans-serif;
    background-color: #2b2b2b;
    color: #fff;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
}

table {
    border-collapse: collapse;
    width: 300px;
    background-color: #1e1e1e;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.1);
    color: #fff;
}

th, td {
    padding: 15px;
    text-align: center;
    border: 1px solid #333;
}

th {
    background-color: #333;
    border-bottom: 2px solid #555;
    border-radius: 5px 5px 0 0;
}

#result, #current {
    font-size: 20px;
    padding: 10px;
    border-bottom: 1px solid #555;
}

button {
    width: 100%;
    height: 100%;
    font-size: 18px;
    border: none;
    outline: none;
    cursor: pointer;
    background-color: #2ecc71;
    color: #fff;
    border-radius: 5px;
}

button:hover {
    background-color: #27ae60;
}

button.operator {
    background-color: #e67e22;
}

button.operator:hover {
    background-color: #d35400;
}

button.equal {
    background-color: #ffd700;
}

button.equal:hover {
    background-color: #d6af00;
}

button.point {
    background-color: #808080;
}

button.point:hover {
    background-color: #696969;
}