Cocoonの目次部分を2カラムにする

toc-2.php

add_filter( 'get_toc_tag', get_toc_tag_custom, 10, 3 );
if ( !function_exists( 'get_toc_tag_custom' ) ):
function get_toc_tag_custom($html, &$harray, $is_widget){
  if ($is_widget) {
    return $html;
  }
  ob_start();?>
  <div class="column-wrap column-2">
    <div class="column-left">
      <?php echo $html; ?>
    </div>
    <div class="column-right">
      <img src="https://wp-cocoon.com/wp-content/uploads/2018/03/screenshot.jpg" alt="挿入する画像">
    </div>
  </div>
  <?php
  $html = ob_get_clean();
  return $html;
}
endif;