public function variantUrlsForTarget(TargetInterface $target, array $variants = [])
    {
        $urls = [
            static::ORIGINAL => $this->storage->url($target->original()),
        ];

        if (in_array(static::ORIGINAL, $variants)) {
            $variants = array_diff($variants, [ static::ORIGINAL ]);
        }

        foreach ($variants as $variant) {
            $urls[ $variant ] = $this->storage->url($target->variant($variant));
        }

        return $urls;
    }