<?php function my_enqueue_block_editor_assets() { wp_enqueue_style( 'my-block-editor-styles', get_theme_file_uri( 'block-editor-style.css' ), array(), filemtime( get_theme_file_path( 'block-editor-style.css' ) ), 'all' ); } add_action( 'enqueue_block_editor_assets', 'my_enqueue_block_editor_assets' );