Hi,
This is not a script, but a spring framework powered enterprise application. It's 100% developed by us. Please ckeck our site for more info.
If you have seen sites with different color scheme it has to be one of our clients.
I am also curious about this, when was your platform launched and when did you start selling your products? I play CS:GO on a daily basis and have seen lots of sites that look exactly like yours.
We have started this project roughly 3 years ago, for 2 of those years we are generating sales. It's highly possible that you have seen it before because we have over 60 clients at the moment. Some of them even have a different design but are still powered by our backend.