<!-- start Simple Custom CSS and JS -->
<style type="text/css">
#hst-calculator {
    max-width: 500px;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 10px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.1);
    font-family: Arial, sans-serif;
    color: #333;
}

#hst-calculator h3 {
    text-align: center;
    color: #333;
    font-size: 24px;
    margin-bottom: 20px;
}

/* Other styles here */
</style>
<!-- end Simple Custom CSS and JS -->
