Anything can be hacked.
If you split your database, use a SQL Server back end rather than an Access back end, convert the front end to an MDE/ACCDE file, use AutoKeys to disable F11, use a custom toolbar/ribbon to restrict the commands available to the user, hide the database window, disable special keys, and disable the SHIFT bypass, then your front end will be secure from anyone save Access experts explicitly trying to hack your program, and if you have someone trying to hack your system, you've got bigger problems.
If you need better security than that, or you absolutely 100% need to prevent someone from pulling your empty forms to see how they're built, then you're going to need to switch platforms entirely.