v0.3.9 - Hard and extreme difficulties

What's changed

• Added Hard and Extreme computer difficulty levels.
• Hard difficulty now scores line extensions and board pressure instead of only choosing nearby cells.
• Extreme difficulty adds stronger defensive weighting and a one-step opponent response estimate.
• Added English and Chinese labels for the new difficulty levels.
• Updated README, roadmap, changelog, package metadata, and tests.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 26 tests.
• git diff --check passed.
• GitHub Actions CI and Pages deployment passed.

Note: the in-app browser could not open the local preview due net::ERR_BLOCKED_BY_CLIENT; UI behavior is covered by source and engine regression tests.

v0.3.8 - Reduced motion support

What's changed

• Added prefers-reduced-motion: reduce support for stone placement transitions.
• Added regression coverage so reduced-motion styling stays in CI.
• Updated README, roadmap, accessibility notes, changelog, and package metadata.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 22 tests.
• git diff --check passed.
• GitHub Actions CI and Pages deployment passed.

v0.3.7 - Accessibility regression checks

What's changed

• Added CI-backed accessibility regression checks for visible board focus styling.
• Added source checks for the polite result live region.
• Added source checks that the latest played stone remains exposed as the current step.
• Updated README, roadmap, accessibility notes, changelog, and package metadata.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 21 tests.
• git diff --check passed.
• GitHub Actions CI and Pages deployment passed.

v0.3.6 - Copy recent match summary

What's changed

• Added a Copy action for the recent completed match summary.
• Copied summaries use the currently selected interface language and include the saved timestamp.
• Copy success and failure are announced through the existing polite live region.
• Updated README, accessibility notes, changelog, and package metadata.
• Added regression coverage for localized recent-match copying.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 18 tests.
• git diff --check passed.
• GitHub Actions CI and Pages deployment passed.

Note: interactive browser smoke testing was not run because the Codex in-app browser is currently blocked from accessing localhost and the GitHub Pages domain by enterprise network policy.

v0.3.5 - Latest move marker

What's changed

• Added a visual marker for the latest played stone.
• Exposed the latest move to assistive technology with aria-current=step and localized cell labels.
• Fixed the empty recent-match state so it follows the selected interface language.
• Added focused regression coverage for localization and latest-move labeling.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 17 tests.
• git diff --check passed.
• GitHub Actions CI and Pages deployment passed.

Note: interactive browser smoke testing was not run because the Codex in-app browser is currently blocked from accessing both localhost and the GitHub Pages domain by enterprise network policy.

v0.3.4 - English and Chinese interface

What's changed

• Added a saved language selector for English and Chinese.
• Localized visible game controls, status text, move history, recent match summaries, and key ARIA labels.
• Preserved compatibility with older saved recent-match summaries.
• Updated README, roadmap, accessibility notes, changelog, and package metadata.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 15 tests.
• Local browser smoke checks passed for default English, Chinese switching, persistence, move labels, recent-match summaries, and mobile layout.
• GitHub Actions CI and Pages deployment passed.

v0.3.3 - Selectable computer difficulty

What's changed

• Added selectable computer difficulty for Computer mode.
• Normal keeps tactical behavior: take a win, block an immediate threat, then choose a nearby cell.
• Easy skips tactical search and only chooses a nearby open cell.
• Added engine test coverage for difficulty-specific move selection.
• Updated README, roadmap, changelog, and package metadata.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 15 tests.
• Local in-app browser smoke check passed for difficulty menu behavior.
• Mobile layout smoke check passed.
• GitHub Actions CI and Pages deployment passed.
• Live GitHub Pages difficulty smoke check passed.

v0.3.2 - Optional game timer

What's changed

• Added an optional elapsed game timer.
• Timer starts on the first move, stops when the match ends, and resets with the board.
• Recent completed match summaries now include duration for timed games.
• Updated README, roadmap, accessibility notes, changelog, and package metadata.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 14 tests.
• Local browser smoke checks passed for timer behavior and mobile layout.
• GitHub Actions CI and Pages deployment passed.
• Live GitHub Pages timer smoke check passed.

v0.3.1 - High contrast display toggle

What's changed

• Added a local high-contrast display toggle for the browser game.
• Made the board edge follow the high-contrast theme instead of keeping the default wood-tone border.
• Updated contributor suggestions after completed player-name and computer-mode work.

Verification

• Node syntax checks passed for src/engine.js and src/main.js.
• Node test suite passed: 14 tests.
• GitHub Actions CI and Pages deployment passed.

v0.3.0 - Player names and computer mode

Highlights

• Added custom black and white player names across status, results, scores, move history, and recent match summaries.
• Added optional local computer mode while keeping two-player as the default.
• Added a deterministic computer move selector that can win, block immediate threats, and choose nearby open cells.
• Added engine tests for computer move selection.
• Included the previous accessibility and recent-match improvements in the 0.3.0 changelog.

Verification

• node --check src/engine.js
• node --check src/main.js
• node --test
• Local Chrome automation for custom names, computer mode, and undo behavior
• GitHub Actions CI
• GitHub Pages deployment