Chore: remove styled system components

[francinelucca]

Migrates leftover styled-system components into css modules

Changelog

Changed

• Migrate leftover styled-system components into css modules

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github (Learn more about how to run integration tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: fe9450b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@primer/react	Major
@primer/styled-react	Major

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

👋 Hi, this pull request contains changes to the source code that github/github depends on. If you are GitHub staff, we recommend testing these changes with github/github using the integration workflow. Thanks!

[primer-integration]

👋 Hi from github/github-ui! Your integration PR is ready: https://github.com/github/github-ui/pull/4099

[Copilot]

Pull Request Overview

This PR migrates leftover styled-system components to CSS modules as part of the effort to remove styled-components from the Primer React codebase. The changes convert styled-components implementations to modern CSS modules with equivalent styling and functionality.

Key changes:

• Convert styled-components to CSS modules for multiple components
• Remove styled-system dependencies and replace with direct CSS properties
• Update component implementations to use modern polymorphic patterns

Reviewed Changes

Copilot reviewed 27 out of 27 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/styled-react/src/components/Text.tsx	Updated Text component types and forward ref implementation
packages/react/src/internal/utils/sharedCheckboxAndRadioStyles.ts	Removed styled-components shared styles file
packages/react/src/internal/components/ValidationAnimationContainer.tsx	Migrated from styled-components to CSS modules
packages/react/src/internal/components/ValidationAnimationContainer.module.css	Added CSS module for validation animation styles
packages/react/src/internal/components/TextInputWrapper.tsx	Removed styled-system ResponsiveValue types
packages/react/src/experimental/UnderlinePanels/UnderlinePanels.tsx	Removed SxProp from component interfaces
packages/react/src/deprecated/UnderlineNav/UnderlineNav.tsx	Migrated from styled-components to CSS modules
packages/react/src/deprecated/UnderlineNav/UnderlineNav.module.css	Added CSS module for UnderlineNav styles
packages/react/src/deprecated/ActionList/Item.tsx	Replaced styled-system get() function with CSS variable
packages/react/src/UnderlineNav/UnderlineNav.tsx	Removed styled MoreMenuListItem component
packages/react/src/Truncate/Truncate.tsx	Replaced styled-system MaxWidthProps with direct type
packages/react/src/Tooltip/Tooltip.tsx	Migrated from styled-components to CSS modules
packages/react/src/Tooltip/Tooltip.module.css	Added CSS module for Tooltip styles
packages/react/src/TextInput/TextInput.tsx	Reordered deprecated props
packages/react/src/TextInput/TextInput.docs.json	Updated documentation for width props
packages/react/src/Text/Text.tsx	Migrated to modern polymorphic pattern
packages/react/src/SkeletonAvatar/SkeletonAvatar.tsx	Simplified style merging without sx utility
packages/react/src/Skeleton/SkeletonBox.tsx	Simplified style merging without sx utility
packages/react/src/SegmentedControl/SegmentedControl.features.stories.tsx	Replaced display prop with inline style
packages/react/src/PageLayout/PageLayout.examples.stories.tsx	Removed commented code
packages/react/src/LabelGroup/LabelGroup.tsx	Migrated from styled-components to CSS modules
packages/react/src/LabelGroup/LabelGroup.module.css	Added CSS module for LabelGroup styles
packages/react/src/FormControl/FormControlLeadingVisual.tsx	Replaced get() function with CSS variables
packages/react/src/DialogV1/Dialog.test.tsx	Replaced fontFamily prop with inline style
packages/react/src/BranchName/tests/BranchName.types.test.tsx	Added explicit type annotation for event parameter
packages/react/src/BranchName/BranchName.tsx	Migrated to modern polymorphic pattern
.changeset/chilled-spoons-roll.md	Added changelog entry

[github-actions]

👋 Hi, there are new commits since the last successful integration test. We recommend running the integration workflow once more, unless you are sure the new changes do not affect github/github. Thanks!

[github-actions]

👋 Hi, there are new commits since the last successful integration test. We recommend running the integration workflow once more, unless you are sure the new changes do not affect github/github. Thanks!

[github-actions]

👋 Hi, there are new commits since the last successful integration test. We recommend running the integration workflow once more, unless you are sure the new changes do not affect github/github. Thanks!