Light/Dark Mode Accessibility Skill

Canonical source: examples/LIGHT_DARK_MODE_ACCESSIBILITY_BEST_PRACTICES.md in mgifford/ACCESSIBILITY.md This skill is derived from that file. When in doubt, the example is authoritative.

Apply these rules whenever implementing or reviewing colour theme support in HTML, CSS, or JavaScript. Only load this skill if the project supports light/dark mode or user theme switching.

Core Mandate

All colour themes must meet WCAG 2.2 Level AA contrast in both light and dark modes, including forced-colours / high contrast modes. Test all three — not just the default.