Fix link and button colors in header footer of Cassiopeia template

[RickR2H]

Rework of issue PR #41749
Pull Request for Issue #42302

Summary of Changes

In previous PR's the colors for the buttons and links in the header and footer where broken. This PR fixed those issues,

• Obsolete styling is removed
• Added correct colors to the header and footer buttons and links
• Fix hover state of scroll to top button

Testing Instructions

Create 3 custom html modules in the positions: topbar / footer / bottom-b
Make sure you toggle the editor to Source code+ (Click in the editor Tools -> Source code+)
Use the code below in the modules and paste as in the Source code+ ans click Save.

<a href="#" class="btn btn-primary">Primary</a>
<a href="#" class="btn btn-secondary">Secondary</a>
<a href="#" class="btn btn-success">Success</a>
<a href="#" class="btn btn-danger">Danger</a>
<a href="#" class="btn btn-warning">Warning</a>
<a href="#" class="btn btn-info">Info</a>
<a href="#" class="btn btn-light">Light</a>
<a href="#" class="btn btn-dark">Dark</a>
<a href="#" class="btn btn-link">Button link</a>
<a href="#">Default Link</a>

Test if all button color are correct, also the hover state.
Test the frontend edit buttons
Switch the scroll to top icon to On in the template settings to test the scroll to top hover color

Actual result BEFORE applying this Pull Request

Some buttons and links texts are not visible

Expected result AFTER applying this Pull Request

All colors are visible

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed

[fgsw]

The Download is not available (Expected — Waiting for status to be reported).

[alikon]

the Prebuilt Download Packages are available here https://artifacts.joomla.org/drone/joomla/joomla-cms/4.4-dev/42504/downloads/72256

[sandewt]

Thanks for this pr.

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[sandewt]

I have tested this item ✅ successfully on 22dc444

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[Quy]

I have tested this item ✅ successfully on 22dc444

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/42504.}

[MacJoom]

Thank you!