public function srcset($reset = true)
    {
        if (empty($this->alternatives)) {
            if ($reset) {
                $this->reset();
            }

            return '';
        }

        $srcset = [];
        foreach ($this->alternatives as $ratio => $medium) {
            $srcset[] = $medium->url($reset) . ' ' . $medium->get('width') . 'w';
        }
        $srcset[] = str_replace(' ', '%20', $this->url($reset)) . ' ' . $this->get('width') . 'w';

        return implode(', ', $srcset);
    }