I am surprised we haven’t had anyone ask yet, usually someone is interested in digging around and finding out more about things work, I know I always am.
All the TGC sites are custom written using Laravel as the framework, this is done mostly because the sites have some requirements that couldn’t be fulfilled, at least well, by WordPress or other CMS. But also Laravel offers a very fast and secure platform to start any development and by pulling in dependencies you can get almost any feature you need.
The forums used to be custom written in PHP by Richard as mentioned above, without any framework. However they were very outdated and written before even PHP5 was a thing. Over the last few years have been also migrated to Laravel to take advantage of its features.
I am here always updating things to make them run smoother and faster.
As for the themes used they are all custom but we always start with Bootstrap 3 as a starting point.
Any other questions let me know.
Windows 7 Pro, Intel i7 3.8 GHz, 16GB DDR3, NVIDIA GTX 780 4GB Superclocked