Fatal error: Uncaught Zend_Cache_Exception: cache_dir "/var/www/pronto/var/page_cache" is not writable in /var/www/pronto/vendor/magento/zendframework1/library/Zend/Cache.php:209
Stack trace:
#0 /var/www/pronto/vendor/magento/zendframework1/library/Zend/Cache/Backend/File.php(180): Zend_Cache::throwException()
#1 /var/www/pronto/vendor/colinmollenhour/cache-backend-file/File.php(87): Zend_Cache_Backend_File->setCacheDir()
#2 /var/www/pronto/vendor/magento/zendframework1/library/Zend/Cache.php(153): Cm_Cache_Backend_File->__construct()
#3 /var/www/pronto/vendor/magento/zendframework1/library/Zend/Cache.php(94): Zend_Cache::_makeBackend()
#4 /var/www/pronto/vendor/magento/framework/App/Cache/Frontend/Factory.php(156): Zend_Cache::factory()
#5 /var/www/pronto/vendor/magento/framework/Cache/Frontend/Adapter/Zend.php(38): Magento\Framework\App\Cache\Frontend\Factory->Magento\Framework\App\Cache\Frontend\{closure}()
#6 /var/www/pronto/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\Framework\Cac in /var/www/pronto/vendor/magento/zendframework1/library/Zend/Cache.php on line 209