Fix: Install screens: “Log In” and "Support link" use old color

[hbhalodia]

Trac ticket: https://core.trac.wordpress.org/ticket/64962

Description

• Add CSS variable for install.css changes.
• Add color hex code for wp_die functions.php code, as the variable was not added before that it executed wp_die.
• Also added fix for setup-config.php if config already exists and related anchors. See before and after Screenshots.

Before	After

Use of AI Tools

• None

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Props hbhalodia, huzaifaalmesbah, audrasjb, wildworks.

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[huzaifaalmesbah]

I think we should use var(--wp-admin-theme-color, #3858e9) for the anchor color instead of var(--wp-admin-theme-color-darker-10). For hover and focus states, we can use var(--wp-admin-theme-color-darker-20, #183ad6).

[audrasjb]

Before:

After:

[audrasjb]

Thanks for the PR, this looks good to me 👍

[audrasjb]

Removing my approval as we also need to update the :focus colors

[audrasjb]

I think we should also update the :focus color accordingly.

[hbhalodia]

Thanks @audrasjb, I have updated to use same color as active and hover.

[audrasjb]

we should also update the :focus color

[hbhalodia]

Thanks @audrasjb, I have updated to use same color as active and hover.

[t-hamano]

What are the reasons for using hardcoded values instead of CSS custom properties?

[hbhalodia]

@t-hamano, This is executed before any of the variables are avialable in the context. Hence adding variable does not works because that variable is not present. Hence added the hardcoded value.

[t-hamano]

I see, thanks!

[t-hamano]

I think the default link color should be #3858e9, no? That is, the value that --wp-admin-theme-color points to when the modern color theme is enabled.

[shail-mehta]

Agreed, the #3858e9 color aligns with the modern theme.