How to create an overarching heading to sections of answers on a matrix qustion

I want to add headings to sections of the matrix section. See attached pictures

I have manged to get the background color changed but do know how to add heading. See below.

How can I add these headers?

Unfortunately, this is not possible to achieve. Only text of rows and columns can be changed. 

As possible workaround you can create two separate matrix tables and set your heading text as label of the matrix field. Or you can add text field above or bellow your matrix table and write description of your field. You can also use Hover Text option to write description of your field.

Feel free to contact us if you have any other questions.