使用WPcode外掛插入以下語法，並於single範本處插入shortcode
$cats = get_the_category();
if ( ! empty( $cats ) ) {
foreach ( $cats as $term ) {
$selector = 'category_' . $term->term_id;
$image = get_field('product_banner', $selector );
echo'<style> .catbanner{ background-image: url('.$image.');} </style>';
}
}