The buttons colors don't adapt properly to the admin scheme color on WP-Admin

[youknowriad]

When you select a deferent admin-scheme, primary buttons change color, but secondary ones don't and the ".page-title-action" buttons don't adapt either.

[youknowriad]

This screenshot shows the result after fixing the issues.

https://core.trac.wordpress.org/ticket/50537

[youknowriad]

I'm not sure whether this requires an a11y feedback because it only touches the admin scheme colors and not the default one but I added the label regardless.

[mapk]

Replying to youknowriad:

I'm not sure whether this requires an a11y feedback because it only touches the admin scheme colors and not the default one but I added the label regardless.

Because it's only touching an alternate admin theme, I don't think it needs an accessibility review based on this slack comment from @joedolson: ​https://wordpress.slack.com/archives/C02S78ZAL/p1593629194193300 but I could be wrong.

I haven't tested your patch but the screenshot looks fantastic. I would also expect the primary color to change on the secondary buttons too.

[youknowriad]

I just noticed the primary hover color is broken, I'll try to fix that a bit later.

[michaelarestad]

Tested. It looks particularly good for the most part. I also see busted primary button hover broken and some of the schemes are a bit light, but perhaps they need a minor updated.

[Joen]

Wonderful small iteration.

I look forward to helping #49999 with improving things overall, there's so much low hanging fruit that just needs a small tweak like this here and there.

[youknowriad]

Thanks all of you for the feedback, I fixed the hover issue for primary buttons.

Now about the low contrast in some admin scheme colors, I think the main issue is not from this ticket but I think that the "highlight color" for these admin schemes is just not a good color. The low contrast can be seen in other places too. So I was hesitant on whether to address it here or not.

@ryelle also proposed that we define a new Sass variable for the default/secondary button colors. In that same vein and since I believe the issue is not that the color between secondary and primary should be different, I'm going to define a variable that if set we fallback to the neutral secondary buttons. It's a measure to ensure the color schemes that don't have good colors won't be impacted by this PR while by default all schemes will adapt (just like the default admin scheme).

[youknowriad]

I updated the patch and kept the default colors for ocean and coffee themes. Let me know how looks it now. If folks agree it's a good shape, it's still time to ship on 5.5.

[youknowriad]

I'd also appreciate a review on #50536 (it should be more straightforward as just a simple fix)

[youknowriad]

Here's another related ticket that I'd appreciate eyes on. #50547

[mcsf]

Replying to youknowriad:

I updated the patch and kept the default colors for ocean and coffee themes. Let me know how looks it now. If folks agree it's a good shape, it's still time to ship on 5.5.

Reviewed, tested, and it looks great.

[ocean90]

It looks like the patch reverts parts of #48585 / #49003. Attached two before/after screenshots with the Midnight scheme.

[youknowriad]

@ocean90 Yes, that's intended, here's my reasoning for adapting the Midnight scheme buttons to the theme color;

• We already use the red button for the primary button
• The color has enough contrast
• While I understand the "color look like a danger button" argument, it also applies to the primary button right now in trunk, IMO we should be consistent.

That said, it's just a variable change, I'd prefer adapting personally but I don't mind reverting too much.

[youknowriad]

In 48342:

Administration: Adapts the secondary buttons colors to the admin schemes.

The admin schemes that don't meet the contrast guidelines are excluded from this change.

Props mapk, michaelarestad, mcsf, ocean90.
Closes #50537.

[youknowriad]

I think some colors in the admin schemes need to be rethought, I created this #50575 to continue the discussion.

[ryelle]

#48998 was marked as a duplicate.

[ryelle]

#48715 was marked as a duplicate.