Superfish menu is not responsive for mobile screens
Superfish has a pretty extensive settings/configuration area, all of which, do take away any necessary programming for menus, and make setting up a complex menu simple.

You are probably missing a mobile declaration somewhere in the settings/config, I would read up on the Superfish documentation here: https://www.drupal.org/node/754652

This also has other useful links that may assist with your situation.