customizer 3.1.10 download /functions.php

Hello,

I am using this theme for my site and I broke the functions.php file by adding some code. Now I’m getting an “Internal Server Error” and the site won’t load at all. I tried to replace the functions.php file with download from customizr 3.1.15 but it’s still not working. Maybe because I am using customizr 3.1.10? Where can I redownload 3.1.10? I don’t have a backup ??