Display a CSS Facebook login button

#es .btn-es-facebook {
    color: #fff !important;
    background-color: #4267b2 !important;
    border-color: #4267b2 !important;
}

.btn-es-facebook { color:... }

if($widget)
    echo $widget->render();

if($widgetType == "login" && $providerType == "facebook")
    echo "blah"; //replace with your button code
else if($widget)
    echo $widget->render();

<?php
/**
* @package JFBConnect
* @copyright (c) 2009-2021 by SourceCoast - All Rights Reserved
* @license http://www.gnu.org/licenses/gpl-2.0.html GNU/GPL
* @version Release v9.0.197
* @build-date 2022/02/01
*/

if (!(defined('_JEXEC') || defined('ABSPATH'))) { die('Restricted access'); };

if ($userIntro != '') {
echo '<div class="sc_social_widget">'.$userIntro."</div>";
}
if ($widgetType == "login" && $providerType == "facebook") { ?>
<div class="jfbconnect-wrapper">
<a href="javascript:void(0)" onclick="jfbc.login.provider('facebook');" class="btn btn-es-facebook btn-sm btn-block">
<i class="fab fa-facebook"></i><?php echo Text::_('FBLOG_JFBC_LAB')?></a>
</div>
<?php }
else if ($widget)
echo $widget->render();

require(JPATH_ROOT.'/components/com_jfbconnect/assets/poweredBy.php');
?>