Why is this giving me a linker error? (random number generation using

NOTE: coord is a std::pair

   class Random
{
public:
    Random()
    {
        gen.seed(rd());
    };
    coord rnd_coord(int x, int y)
    {
        std::uniform_int_distribution<> dist_x(0, x - 1);
        std::uniform_int_distribution<> dist_y(0, y - 1);
        coord temp;
        temp.first = dist_x(gen);
        temp.second = dist_y(gen);
        return temp;
    }
private:
    static std::random_device rd;
    static std::mt19937 gen;
};

Then in main.cpp

int x;
Random R;
coord C;
C = R.rnd_coord(10, 10);
std::cout << C.first << ", " << C.second << std::endl;
std::cin >> x;

return 0;

Im doing some tests with but I'm having a lot of issues with it :(, tbh I havent programmed in a while. Anyway, I want to make a helper function that will return random coordinates in the specified bounds, said function is in "snake_utility.h", but as it was giving me errors i put it in a class, and now I get linker errors:

Error 1 error LNK2001: unresolved external symbol "private: static class std::random_device Random::rd" (?rd@Random@@0Vrandom_device@std@@A) C:\Users\Reethok\Desktop\C++\Pet Projects\Snake\Snake\main.obj Snake Error 2 error LNK2001: unresolved external symbol "private: static class std::mersenne_twister_engine Random::gen" (?gen@Random@@0V?$mersenne_twister_engine@I$0CA@$0CHA@$0BIN@$0BP@$0JJAILANP@$0L@$0PPPPPPPP@$06$0JNCMFGIA@$0P@$0OPMGAAAA@$0BC@$0GMAHIJGF@@std@@A) C:\Users\Reethok\Desktop\C++\Pet Projects\Snake\Snake\main.obj Snake Error 3 error LNK1120: 2 unresolved externals C:\Users\Reethok\Desktop\C++\Pet Projects\Snake\Debug\Snake.exe 1 1 Snake

Thanks in advance!