<?php
/** add additional classes / id to the facetwp-template div generated by a facetwp
** layout template
**/
add_filter( 'facetwp_shortcode_html', function( $output, $atts) {
if ( $atts['template'] = 'example' ) { // replace 'example' with name of your template
/** modify replacement as needed, make sure you keep the facetwp-template class **/
$output = str_replace( 'class="facetwp-template"', 'id="masonry-container" class="facetwp-template small-up-1 medium-up-2 large-up-3"', $output );
}
return $output;
}, 10, 2 );