Full width header in a boxed layout

Jeg vil at toppteksten/bunnteksten min skal fylles ut i bredden fra bokslayout 1440. Jeg har prøvd «alt» ... noen hurtigløsninger for dette? 

Hello, please post your question in english. 
Please always include the live URL, PHP version, template & astroid version, and template name.

I did write in english...  autotranslate apperantly?
It's a new, not live site yet - you find it here: ny.astec.no -  ny.astec.no/produkter (separate layouts/templates)
As you can see I have found a way to "break out" of the box by using -100vw in margins in the Header position under layout, but the "original" heading is in the back - and it doesn't translate to the sticky header/ logo in top disappear

Template Ultimate/ Astroid 3.3.5/ PHP 8.3

I'm bit of a novice, so probably a easy fix but not sure where.. As a custom CSS in the template / CSS in the actual header position?

Appreciate your feedback!
 

The page is currently unavailable, so we can't see anything. Please contact us again when the page is accessible. There is also documentation available for layout configuration. www.joomlaplates.de/template-configuraton/layout.html
 

You can't see  ny.astec.no/produkter/ ? How is that possible? 

www.joomlaplates.de/template-configuraton/layout.html Ups!Seite nicht gefunden