Responsive take1

Hi all. how are you.
I got a project from work to design a new website for desktop and mobile.
I have some experience with axure but its my first time doing something responsive.
I followed tutorial on youtube and build something very simple in 3 dimensions 360px/768px/1200px.
when i test in chrome dev tools and tried to view the prototype in Galaxy S5 (360X640px) or iPad (768x1024px) it doesn’t fit the screen size and looks smaller even though i build with the correct size
What am i doing wrong?
i really hope to understand this very quickly.

Thank you All

AMIR

mobile first.rp (79.7 KB)