body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    color: #333;
    margin: 0;
    padding: 20px;  
}

.InputNum {
    width: 60px;
    height: 60px;
    font-size: 24px;
    margin: 5px;
    cursor: pointer;
}
#calculator {
    display: flex;
    flex-wrap: wrap;
    max-width: 250px;
    margin: auto;
}
.Oper {
    background-color: rgba(0, 204, 255, 0.597);
    color: white;
}
#Display {
    width: 200px;
    height: 60px;
    background-color: #fff;
    border: 1px solid #ccc;
    text-align: center;
    line-height: 60px;
    font-size: 24px;
    margin-bottom: 10px;
}

#Equals {
    background-color: #4CAF50;
    color: white;
}
#Clear {
    background-color: #f44336;
    color: white;
    width: 200px;
}