Header and Footer Different Format in Mirrored Layout

Hello everyone,
first of all I would like to apologize for any language errors; clarified this I would like to create a Mirrored Page Style with different headers and footers for left or right pages.

I created my style, enabled the header and footer and I have also checked the “Same content on left and right pages” box.
In this way I can create headings with different contents, for example having the left header with:
| PAGE NUMBER | DOCUMENT NAME |
and have on the right page with
| AUTHOR | PAGE NUMBER |

My problem is that I would like have different format of header (as border and background color) like contents (for example have blue background and yellow border on the left page and red background and green border on the right), but unfortunately the “More” button at the bottom ( in the Page Style - Header) only change the right header; how can I change the other?

PS: For now i have used a workaround creating two different page style (a “left page” style and a “right page” style)and alternate them. But it would be great have a way to do this with a single mirrored style

First, I think you made a typo when stating you also checked the “Same content on left and right pages” box. In fact, you unchecked the box.

With the box unchecked, you allowed different contents on left and right pages. “Contents” extends also to formatting. All you have to do is assign built-in paragraph styles Header Left and Header Right to the respective headers.

When this is done, you customise separately the styles to your taste.

Reminder: as shipped thses styles already have tabs sets so that the first Tab puts you at page enter with center alignment and a second Tab flushes text to right margin.