Add offcanvas mobile navigation to the header and remove the Varbase branding from the footer

Problem/Motivation

Depends on #3620712. The header sets the icon_color prop on the Icon Toggle component, and the recipe's shipped component config does not declare it yet, so without that issue's re-export the config import rejects the value and the site install aborts. Verified both ways: with the current component configs the install exits 1 on 'icon_color' is not a prop on this version of the Component; with the re-export in place the same regions import and the install exits 0.

Two gaps in the header and footer page regions the recipe ships.

The header has no mobile navigation. It carries six component-tree entries and no offcanvas menu, so on a small viewport there is no way to reach the main menu.

The footer carries Varbase and Vardot branding, which does not belong in a site template that is meant to be someone else's newsroom. On the current branch the footer's html-code block renders:

• logo.svg with alt="Varbase logo"
• a "Powered by Vardot" block with vardot-logo.svg
• a tagline linking to vardot.com: "Enjoy the free software, or get a quote for enterprise support and fully functional websites."

Steps to reproduce

1. Install the site template on Varbase 11.
2. Narrow the viewport to a phone width. There is no menu toggle in the header.
3. Look at the footer. It advertises Varbase and Vardot.

Proposed resolution

Update the two page regions.

Header, 6 entries to 12. Adds offcanvas-menu for mobile navigation, with the main menu in its menu slot, the footer menu in its utility slot and the search exposed filter in its search slot; plus a Newsletter button, a group, and a second main-menu placement. No theme change is needed: offcanvas-menu already exists as a complete SDC in the theme, and its pinned component_version: b15fbf5fea2cb26b matches the active version generated on install.

Footer, 8 entries to 9. Replaces the Varbase and Vardot branding above with the theme's own wordmark and ©2026, The Right Up. All Rights Reserved., and moves the footer to a dark treatment.

Two things the reviewer should look at deliberately rather than discover in the diff.

The footer drops menu.secondary. That is a behaviour change and it needs the maintainer's confirmation that it is intended. It came from the source the regions were exported from; it is not an accident of the export, but it is also not something this issue can decide.

The header section stays light, deliberately. The design these regions come from uses a dark header, and the footer here does go dark. The header cannot, yet: it places system_branding_block, and the theme has no way to render the white wordmark through that block, so a dark header would show a black-ink logo on black. Verified by computed style. That is filed separately as #3620716, and once it lands the header section can take the dark background. Shipping a legible header now is better than shipping the intended colour with an invisible logo. For the same reason the search toggle uses icon_color: text-body, the component's own default, rather than text-white.

Remaining tasks

• ✅ File an issue
• ✅ Addition/Change/Update/Fix
• ✅ Testing to ensure no regression
• ➖ Automated unit/functional testing coverage
• ➖ Developer Documentation support
• ➖ User Guide Documentation support
• ❌ UX/UI designer responsibilities
• ✅ Accessibility and Readability
• ❌ Reviewed by a human
• ❌ Code review by maintainers
• ❌ Full testing and approval
• ❌ Credit contributors
• ❌ Review with the product owner
• ❌ Update Release Notes
• ❌ Release

User interface changes

• The header gains a working mobile navigation menu.
• The footer no longer carries Varbase or Vardot branding, and is dark.

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• Added an offcanvas mobile navigation menu to the header, and replaced the Varbase and Vardot branding in the footer with the site template's own.