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+---
+phase: 12
+slug: dark-mode-visibility-fixes
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-01
+---
+
+# Phase 12 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | Vitest ^4.1.1 (node environment) + @testing-library/react |
+| **Config file** | `vitest.config.ts` |
+| **Quick run command** | `npm test -- --reporter=verbose` |
+| **Full suite command** | `npm test` |
+| **Estimated runtime** | ~10 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `npm test -- --reporter=verbose`
+- **After every plan wave:** Run `npm test`
+- **Before `/gsd:verify-work`:** Full suite must be green + visual browser verification in dark mode
+- **Max feedback latency:** 10 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 12-01-01 | 01 | 1 | h2 headings visible in dark mode | unit | `npm test -- src/components/wizard/BackendSelectionStep` | ✅ | ⬜ pending |
+| 12-01-02 | 01 | 1 | h2 headings visible in dark mode | unit | `npm test -- src/components/wizard/RemoteConfigStep` | ✅ | ⬜ pending |
+| 12-01-03 | 01 | 1 | h2 headings visible in dark mode | unit | `npm test -- src/components/wizard/DeploymentStep` | ✅ | ⬜ pending |
+| 12-01-04 | 01 | 1 | h2 headings visible in dark mode | unit | `npm test -- src/components/wizard/ReviewStep` | ✅ | ⬜ pending |
+| 12-01-05 | 01 | 1 | DeploymentStep labels/controls visible | unit | `npm test -- src/components/wizard/DeploymentStep` | ✅ | ⬜ pending |
+| 12-01-06 | 01 | 1 | Select element styled for dark mode | unit | `npm test -- src/components/ui/FieldRenderer` | ✅ | ⬜ pending |
+| 12-01-07 | 01 | 1 | ReviewStep checkbox styled | unit | `npm test -- src/components/wizard/ReviewStep` | ✅ | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+Existing infrastructure covers all phase requirements. No new test files or fixtures needed.
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Dark mode visual correctness | All elements visible on dark bg | jsdom does not resolve CSS custom properties | Toggle dark mode in browser, verify all headings/labels/controls are readable on dark background |
+| Select dropdown appearance | Select bg/text correct in dark mode | Native `<option>` rendering is browser-dependent | Open select in dark mode on Chrome/Edge, verify text is legible |
+| Native checkbox/radio accent | Controls use primary accent color | CSS `accent-color` not testable in jsdom | Toggle checkboxes/radios in dark mode, verify accent color matches primary theme |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 10s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending