public static function tag($tag, $attr = [], $html = '')
    {
        // Build attributes
        $attributes = [];
        foreach ($attr as $name => $value) {
            $attributes[] = $name.'="'.$value.'"';
        }

        if (in_array($tag, self::$voidElements)) {
            return '<'.$tag.(!empty($attributes) ? ' '.implode(' ', $attributes) : '').'>';
        } else {
            return '<'.$tag.(!empty($attributes) ? ' '.implode(' ', $attributes) : '').'>'.$html.'</'.$tag.'>';
        }
    }