Fatal error: Uncaught Error: Call to undefined function post_class() in X:\wordpress\Nieuwe map\wp-content\themes\twentyseventeen\template-parts\page\content-front-page-panels.php:15 Stack trace: #0 {main} thrown in X:\wordpress\Nieuwe map\wp-content\themes\twentyseventeen\template-parts\page\content-front-page-panels.php on line 15