fix(ios): translucent toolbar blur no longer obscures entering page title

[liamdebeasi]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: #19158

What is the new behavior?

• Added '.header-background where the backdrop filter will be applied to.
• Updated animation to translate the toolbar bg instead of fade out when the header is translucent

Does this introduce a breaking change?

• Yes
• No

Other information

[brandyscarney]

Wouldn't this apply to MD too?

[liamdebeasi]

It's in the header.ios.scss file, so it should be fine, right? Or do I still need .header-translucent-ios .header-background?

[brandyscarney]

I thought that scoped used to do that, but I'm seeing it work fine. I wonder why we specify the class + mode in all of the CSS files though instead of just using .header-translucent or ion-header then.