Contoso University is a C# demo based on the ASP.Net platform using a Model View Controller (MVC) structure. This demonstration was created by Microsoft, However, I have adapted it and put a personal spin on things to get it to how I like it.
if this were to go public it would not need much work it has 2fa built into it and is overall complete and secure. One benefit to using the ASP.net platform is all your security is handled by Microsoft so that is one less worry.
This example has no live preview as I do not have a host that Supports ASP.net. However, you may view the code via the link below. This demo has two parts. A front consumer-facing webpage and a student portal. The front-facing consumer page is what you would expect. It has all the information about this fictional university laid out, with a 'contact us' form etc. But the student and teacher portal has a few tricks. Teachers can access the backend of this site to add students and add marks classes etc.