Navbar animation responsivness and fixed in place not working

Hi, so i wanted to make a navbar animation, but i cannot make the navbar responsive AND animated AND fixed in place (so it moves down when im scrolling). I am going insane, heres the problem below. The problem is that because the navbar is not inside hero section i cannot make this animation and i dont know how else i can do it while containing both animation, responsivness and it being fixed in place - desperate design student.