Tailwind CSS v4

Verify before implementing: For v4-specific syntax (@theme, @variant, CSS-first config), look up current docs via Context7 (query-docs) before writing code. Tailwind v4 changed significantly from v3 and training data may be stale.

Working rules

• Keep utility names as complete source literals and confirm their files are scanned.
• Use shared design tokens and one consistent visibility mechanism.
• Inspect generated CSS after source/configuration changes; JSX strings alone do not prove utilities exist.
• Test scrolling, overlays, and focus behavior in a browser when layout containment changes.

Coding Rules