To be sure with @alessioalex. What you are requesting isn't feasible.
There's a limited quantity of protection you will get in the fundamental "disable context menu" function. It is not secure, however it does safeguard you from individuals who have no idea what they are doing or who can not be bothered down the sink their time getting past it.
But there's zero additional protection available from doing anything further than that inside a browser atmosphere, because all of your code and graphics can be found which is trivial for any user with even limited understanding to access it.
You say you've heard every argument about copy protection on the internet, but when you are asking this you clearly haven't understood individuals arguments.
Main point here: If copy protection is the fact that vital that you you, a web site may be the wrong atmosphere for the content.
Most likely not something you're searching for, because the workaround with this technique is always to use IE, but later on you could use CSS Transitions to schedule "disappearance" from the content and totally reset it with JS periodically :)