8342705: Add dark mode for docs

[hns]

Please review an enhancement to add a dark theme to javadoc-generated API documentation. There is a new button in the top right corner that brings up a menu to switch between themes. Available options are "Light", "Dark", and "System Setting" (following the system-wide theme setting). The selected theme is stored and preserved across browser sessions.

Generated docs can be viewed here (iteration 5, module java.base only).

Screenshots below show both themes and how to switch between them.

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Progress

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Issue

• JDK-8342705: Add dark mode for docs (Enhancement - P4)

Reviewers

• Chen Liang (@liach - Reviewer)

Reviewing

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Update a local copy of the PR:
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$ git pull https://git.openjdk.org/jdk.git pull/26185/head

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$ git pr checkout 26185

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[bridgekeeper]

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[openjdk]

@hns This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8342705: Add dark mode for docs

Reviewed-by: liach

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At the time when this comment was updated there had been 498 new commits pushed to the master branch:

• 4ed268f: 8362304: Fix JDWP spec w.r.t. OPAQUE_FRAME and INVALID_SLOT errors
• 0b2d081: 8365636: JFR: Minor cleanup
• 999761d: 8365312: GCC 12 cannot compile SVE on aarch64 with auto-var-init pattern
• ... and 495 more: https://git.openjdk.org/jdk/compare/5c67e3d6e573e5e1fc23f16b61e51fda7b3dd307...master

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[openjdk]

@hns The following label will be automatically applied to this pull request:

• javadoc

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[mlbridge]

Webrevs

• 02: Full - Incremental (a12a273c)
• 01: Full (dfb3b247)
• 00: Full (a35877de)

[hns]

I'm finding the orange link color a bit too flashy, so I created a new snapshot that uses a pale blue color for links. This results in a less striking color scheme that is more in line with the default light theme IMO.

I also realized that there is no requirement in terms of a11y to use a particular link color for navigation links, so I switched to a neutral color for links in the subnavigation and sidebar, which further "calms" the layout and improves readability IMO.

I haven't updated the PR yet and posting this here for discussion.

[nizarbenalla]

I don't think you can nest rules here, the browser may skip/ignore them.

[hns]

It works for me, I've tried it on Firefox, Safari and Chrome.

Documentation of CSS nesting: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_nesting/Using_CSS_nesting
It's implemented in all major browsers: https://caniuse.com/?search=css%20nesting

[hns]

I updated the PR with changes described in my previous comment.

[hns]

Another iteration on this PR, moving the theme switcher icon in line with the main navigation links in the top navigation bar.

I updated screenshots and demo docs.

[hns]

/integrate

[openjdk]

Going to push as commit 0755477.
Since your change was applied there have been 498 commits pushed to the master branch:

• 4ed268f: 8362304: Fix JDWP spec w.r.t. OPAQUE_FRAME and INVALID_SLOT errors
• 0b2d081: 8365636: JFR: Minor cleanup
• 999761d: 8365312: GCC 12 cannot compile SVE on aarch64 with auto-var-init pattern
• ... and 495 more: https://git.openjdk.org/jdk/compare/5c67e3d6e573e5e1fc23f16b61e51fda7b3dd307...master

Your commit was automatically rebased without conflicts.

[openjdk]

@hns Pushed as commit 0755477.

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