Hello,
https://demo.gavick.com/joomla25/musicstate/
With firefox version 46.0.1, login box is not showing correct, can you please find and fix the issue. and let us know what is causing that, we are also using this template, and we are facing the same issue on our live site as well.
But unfortunately we found the same on your demo site as well.
Please note, we are facing this issue only after upgrading the firefox to the latest version 46.0.1, before that we were not facing this issue.
Please help us to fix that issue ASAP.
Thank you,