Improve styling to fit the new section order
Improve styling to fit the new section order

- Change hero koro color to white
- Add section content to projects section to modify content
- Add projects koro
- Change banners top margin so its not too big
- Add projects section specific CSS, same as themes section
- Remove footer top margin to get rid of a white box

City-of-Helsinki/digihel,City-of-Helsinki/digihel,City-of-Helsinki/digihel,City-of-Helsinki/digihel