Encrypt or protect web system files

Thanks for reading my question. I have read all the questions regarding with Encryption of web pages but they do not answer my problem at all.

I know that if the user can see the page, then he can extract images and source code whatsoever. I have no problem with that or with the user right clicking the page or whatever he wants.

The problem is that I have developed a web system in html+php+mysql that is supossed to run on a server that is not accesible by any user than me. But I have a client who needs the system tu run on a local host with local database so he can have a closed network with no internet access. I can do that but I don't want him or any future client with same requests to have access to the files on root folder of his local host. Does this concern has any sense? Maybe I'm missing something obvious but I appreciate your answers!