Great design!!! Perhaps you can tell us a bit more about what you're trying to accomplish with the design.
Let's start with: What would you like the text in the hero section to do? Right now it's competing for space with the woman's head.
The image of the woman is also set to contain, but you might want to switch that to cover starting in mobile landscape view. This will prevent the gap from appearing at the bottom.
Edit: OH. Now I see what you're talking about. There's more. Delete the height properties for each section. That'll fix 99% of this. In mobile you'll still see an issue in the main section, and that's because there's another height property set for it in Tablet view.