styles.php

if ( function_exists( 'register_block_style' ) ) {
	function prefix_register_block_styles() {
		/**
		 * Register stylesheet
		 */
		wp_register_style(
			'prefix-stylesheet',
			plugins_url( 'style.css', __FILE__ ),
			array(),
			'1.0.0'
		);

		/**
		 * Register block style
		 */
		register_block_style(
			'core/image',
			array(
				'name'         => 'glitch',
				'label'        => '__( 'Glitch Filter', 'coblocks' )',
				'style_handle' => 'prefix-stylesheet',
			)
		);
	}

	add_action( 'init', 'prefix_register_block_styles' );
}