PHP / HTML / CSS / FileMaker PHP API条件格式<td>

I'm fairly new to PHP and I only am using it because I need to publish some of my FileMaker database on the web.

What I would like to do is have a cell in a table to change colors based on a field in my FileMaker database called "ReferralStatus" which will only ever have a value of "Red", "Green" or "Yellow"

How would I go about accomplishing this with PHP/HTML/CSS ? I was thinking use an if/else conditional to check the status and assign a class but how would I apply that to the element?

Right now I am using a foreach loop to generate the table row and table data columns.

The code below worked for me:

    <?php 
    foreach($relatedRecords as $related_record) {
    echo 
    '<tr>' . 
    '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::DateReceived') . '</td>' . 
    '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::FirstName') . '</td>' . 
    '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::LastName') . '</td>' . 
    '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::FullAddress') . '</td>' . 
    '<td style="border: 1px solid black; padding: 3px; background-color: '. $related_record->getField('ReferredLeadsToCustomerLogins::ReferralStatus') . ';">' . $related_record->getField('ReferredLeadsToCustomerLogins::ReferralStatus') . '</td>' .
    '</tr>';
    } 
?>

HTML/PHP:

        <?php 
        foreach($relatedRecords as $related_record) {
        echo 
        '<tr>' . 
        '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::DateReceived') . '</td>' . 
        '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::FirstName') . '</td>' . 
        '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::LastName') . '</td>' . 
        '<td style="border: 1px solid black; padding: 3px; background: #cacaca;">' . $related_record->getField('ReferredLeadsToCustomerLogins::FullAddress') . '</td>' . 
        '<td style="border: 1px solid black; padding: 3px; background-color: '. $related_record->getField('ReferredLeadsToCustomerLogins::ReferralStatus') . ';">' . $related_record->getField('ReferredLeadsToCustomerLogins::ReferralStatus') . '</td>' .
        '</tr>';
        } 
    ?>

PHP/HTML:

<td class="<?php echo $ReferralStatus; ?>"> foo </td> 

$ReferralStatus is one of "Green", "Red" or "Yellow", so that the line will output sth like this:

<td class="Red"> foo </td>

CSS:

.Red {
  background-color: red;
}
.Green {
  background-color: green;
}
.Yellow {
  background-color: yellow;
}