sticky header desktob & mobile

Hi guys,
i have the requests regarding the sticky header:

1. is it possible to keep the sticky header (desktop version) transparent during scrolling down the page?
2. is it possible to change the default color (“white”) of sticky header (desktop & mobile version) to a different color? It seems not to work by using the theme options!
3. i wonder if its possible to have a sticky header (menu) for mobile version after theme update?

thanks for helping!
best regards