Strategy of converting code from C++11 to C++98?

I have a project written in C++11. As C++11 is widely accepted, the project works well up to now, until I have to run it in a environment which not support C++11.

I have already used std::shared_ptr, auto, std::intializer_list, nullptr enum class,chrono, std::vector<int> x{1,2,3,4} and many other C++11 technique everywhere in the project.

How can I move the big project in C++11 to C++98?

I apologize if it is a stupid problem, Thanks for your time.