I18n data

[JayPanoz]

This creates a JSON file for language-specific values in ReadiumCSS-base module so that they can be accessible to external consumers of ReadiumCSS.

A use case would be to adjust the value you submit for line height to the Preferences API in Navigators depending on the language, or adjust font-family putting the value in the selection as sort of a default value.

[mickael-menu]

What would be the strategy for a RS to figure out which line height compensation to use? Here's an attempt:

• Find the key with match the publication's full BCP-47 language + region code.
• If no match, find the key after removing the region code (only BCP-47 language code).
• If no match, use default (or ignore, because the line height compensation should be 1).

[JayPanoz]

Yeah that makes sense as I treated it like this lately as it was the most obvious way to do it.

We'd better document it for clarity. I am also thinking about the case where Latin may not be the default script of the app, in which case we should warn to not blindly apply this logic.

[Copilot]

Pull request overview

Exposes more ReadiumCSS variable data as published JSON/docs for external consumers, especially language-specific font-family and line-height defaults, and wires the build to generate a Markdown reference from those datasets.

Changes:

• Added new published variable datasets (i18n.json, settings.json) and converted existing exported vars JSON files to unprefixed keys, with PostCSS now adding the --RS__ prefix at build time.
• Updated the base stylesheet and regenerated compiled CSS so language-specific defaults come from imported i18n data instead of hardcoded values.
• Added generated/reference documentation for the new data, updated EPUB/migration docs, and bumped the package version/build pipeline.

Reviewed changes

Copilot reviewed 15 out of 30 changed files in this pull request and generated 11 comments.

Show a summary per file

File	Description
scripts/generate-vars-doc.js	New script to build css/vars/CSS-Variables.md from exported JSON data.
package.json	Adds vars-doc generation to the build and bumps package version.
docs/ReadiumCSS_docs/OEBPS/toc.ncx	Adds EPUB TOC entry for the new i18n migration note.
docs/ReadiumCSS_docs/OEBPS/Text/Section-028.xhtml	Adds EPUB migration-guide content about exposed i18n data.
docs/ReadiumCSS_docs/OEBPS/Text/nav.xhtml	Adds EPUB nav link for the new section.
docs/ReadiumCSS_docs/OEBPS/content.opf	Updates EPUB modified timestamp metadata.
docs/CSS28-migration_guide.md	Adds migration-guide section about i18n stacks and generated vars docs.
css/vars/settings.json	New published mapping of stylesheet variants to disabled/added user settings.
css/vars/pagination.json	Publishes pagination defaults with unprefixed JSON keys.
css/vars/i18n.json	New published language-to-font/line-height mapping.
css/vars/fontStacks.json	Publishes default/Japanese font stacks with unprefixed JSON keys.
css/vars/CSS-Variables.md	Generated reference document for exported CSS variable data.
css/vars/colors.json	Publishes color defaults with unprefixed JSON keys.
css/src/modules/ReadiumCSS-base.css	Switches base language defaults to imported i18n variables.
css/postcss.config.js	Configures JSON import plugin to prepend --RS__.
css/dist/webPub/ReadiumCSS-webPub.css	Regenerated webPub bundle header/version.
css/dist/rtl/ReadiumCSS-default.css	Regenerated RTL default bundle header/version.
css/dist/rtl/ReadiumCSS-before.css	Regenerated compiled RTL base bundle with imported i18n vars.
css/dist/rtl/ReadiumCSS-after.css	Regenerated RTL after bundle header/version.
css/dist/ReadMe.md	Updates published dist README content.
css/dist/ReadiumCSS-default.css	Regenerated default bundle header/version.
css/dist/ReadiumCSS-before.css	Regenerated compiled base bundle with imported i18n vars.
css/dist/ReadiumCSS-after.css	Regenerated after bundle header/version.
css/dist/cjk-vertical/ReadiumCSS-default.css	Regenerated CJK vertical default bundle header/version.
css/dist/cjk-vertical/ReadiumCSS-before.css	Regenerated compiled CJK vertical base bundle with imported i18n vars.
css/dist/cjk-vertical/ReadiumCSS-after.css	Regenerated CJK vertical after bundle header/version.
css/dist/cjk-horizontal/ReadiumCSS-default.css	Regenerated CJK horizontal default bundle header/version.
css/dist/cjk-horizontal/ReadiumCSS-before.css	Regenerated compiled CJK horizontal base bundle with imported i18n vars.
css/dist/cjk-horizontal/ReadiumCSS-after.css	Regenerated CJK horizontal after bundle header/version.

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