class AddCssCommand

class AddCssCommand implements CommandInterface {
    
    /**
     * Arrays containing attributes of the stylesheets to be added to the page.
     *
     * @var string[][]|string
     */
    protected $styles;
    
    /**
     * Constructs an AddCssCommand.
     *
     * @param string[][]|string $styles
     *   Arrays containing attributes of the stylesheets to be added to the page.
     *   i.e. `['href' => 'someURL']` becomes `<link href="someURL">`.
     */
    public function __construct($styles) {
        if (is_string($styles)) {
            @trigger_error('The ' . __NAMESPACE__ . '\\AddCssCommand with a string argument is deprecated in drupal:10.1.0 and is removed from drupal:11.0.0. See http://www.drupal.org/node/3154948', E_USER_DEPRECATED);
        }
        $this->styles = $styles;
    }
    
    /**
     * {@inheritdoc}
     */
    public function render() {
        return [
            'command' => 'add_css',
            'data' => $this->styles,
        ];
    }

}