Enqueue WP Styles with versioning to avoid cache when updated

/**
 * Enqueue styles and scripts
 */

	function enqueue_styles()
	{
		wp_enqueue_style( 'my-style', PLUGIN_URI.'my.css', array(), filemtime(PLUGIN_PATH.'my.css'), 'all' );
	}

	add_action( 'wp_enqueue_scripts', array($this, 'enqueue_styles'));