Responsive header refactor

.claude/skills/css-nesting-conventions.md

@@ -0,0 +1,121 @@
+# CSS Nesting Conventions
+
+## Overview
+
+This project uses **native CSS nesting** (W3C CSS Nesting spec), not Sass/SCSS. They look similar but behave differently in one important way: native CSS does not support BEM-style `&` concatenation for child element selectors.
+
+## The key rule
+
+> `&` must be followed by a combinator (space, `>`, `~`, `+`) or a selector starting with `.`, `#`, `:`, `[`, or `*`. It **cannot** be followed by a bare identifier or `__` prefix.
+
+## ❌ What NOT to do — Sass-style BEM concatenation
+
+```css
+/* Sass/SCSS — does NOT work in native CSS */
+.demo-controls {
+  padding: 1.6rem;
+
+  &__heading {        /* ← Invalid native CSS — esbuild converts to :is(__heading) */
+    font-size: 1.1rem;
+  }
+
+  &__fields {         /* ← Invalid native CSS */
+    display: flex;
+  }
+}
+```
+
+**Why it silently fails**: esbuild converts `&__heading` to `:is(__heading)`, which tries to match an HTML element named `__heading`. No such element exists, so the styles are never applied. There's no error — just missing styles.
+
+The build will show this warning:
+```
+▲ [WARNING] Cannot use type selector "__heading" directly after nesting selector "&" [css-syntax-error]
+  CSS nesting syntax does not allow the "&" selector to come before a type selector.
+```
+
+## ✅ Correct patterns
+
+### Nested descendant (preferred for BEM child elements)
+
+```css
+.demo-controls {
+  padding: 1.6rem;
+
+  & .demo-controls__heading {   /* space + full class name */
+    font-size: 1.1rem;
+  }
+
+  & .demo-controls__fields {
+    display: flex;
+  }
+}
+```
+
+### Flat top-level rules (also valid — avoids repetition for deeply nested structures)
+
+```css
+.demo-controls {
+  padding: 1.6rem;
+}
+
+.demo-controls__heading {
+  font-size: 1.1rem;
+}
+
+.demo-controls__fields {
+  display: flex;
+}
+```
+
+### Same-element modifier (this IS valid)
+
+```css
+/* & followed by a class — matches the same element that also has this class */
+.button {
+  background: blue;
+
+  &.button--large {   /* ← valid: & immediately followed by . */
+    padding: 2rem;
+  }
+
+  &:hover {           /* ← valid: & immediately followed by : */
+    background: darkblue;
+  }
+
+  &[disabled] {       /* ← valid: & immediately followed by [ */
+    opacity: 0.5;
+  }
+}
+```
+
+### Pseudo-elements and pseudo-classes
+
+```css
+.component {
+  &::before { content: ""; }    /* ✅ valid */
+  &::after  { content: ""; }    /* ✅ valid */
+  &:focus   { outline: auto; }  /* ✅ valid */
+  &:not(.active) { opacity: 0.5; }  /* ✅ valid */
+}
+```
+
+### Media / container queries inside a rule
+
+```css
+.component {
+  grid-template-columns: 1fr;
+
+  @media (width >= 768px) {
+    grid-template-columns: 1fr 2fr;  /* ✅ valid — query wraps the property */
+  }
+}
+```
+
+## Spot-check during review
+
+If you see `&__` or `&-` in a `.vue` `<style lang="css">` block, it's Sass syntax and will not work. Convert it to `& .full-class-name` or lift it to a top-level rule.
+
+## Related
+
+- `CLAUDE.md` → Styling Methodology section
+- `css-grid-max-width-gutters.md` — example of correct native nesting in a grid utility

.claude/skills/index.md

@@ -33,6 +33,7 @@ Each skill is a single markdown file named `<area>-<task>.md`.
 ├── component-dynamic-slots.md        — named dynamic slots ($slots iteration) vs indexed dynamic slots (itemCount pattern)
 ├── component-local-style-override.md — styleClassPassthrough + scoped style block for per-usage visual customisation
 ├── component-prop-driven-container-layout.md — vary CSS grid layout inside @container queries using data-* attribute selectors
+├── css-nesting-conventions.md                — native CSS nesting rules: why &__child Sass BEM concatenation silently breaks, correct patterns
 ├── css-grid-max-width-gutters.md             — cap a centre grid column width by growing gutters, with start/center alignment variants
 ├── css-animation-utilities.md                — scroll-driven animation utility classes: scroller-x (carousel), entry-zoom-reveal, entry-slide-in, entry-exit-blur, auto-rotate
 ├── component-aria-landmark.md        — useAriaLabelledById composable: aria-labelledby for section/main/article/aside tags
@@ -44,6 +45,7 @@ Each skill is a single markdown file named `<area>-<task>.md`.
 ├── new-app-scaffold.md               — scaffold a new Nuxt consumer app extending this layer (package.json, nuxt.config, app structure, CLAUDE.md)
 ├── qa-panel.md                       — collapsible dev-only panel for toggling component props live on a page (demo pages and consuming apps)
 ├── release-notes.md                  — produce release notes as a fenced markdown block from git log
+├── pull-request-description.md       — produce a PR description as a fenced markdown block from git diff vs main
 ├── composable-canonical-url.md       — useCanonicalUrl: set <link rel="canonical"> from runtimeConfig.public.canonicalHost; layout setup, node types
 ├── composable-whatsapp.md            — useWhatsApp: open pre-filled wa.me link from form payload; runtime config, security, usage
 ├── composable-zod-validation.md      — useZodValidation: schema-driven form validation, error binding, submit flow, API error push

.claude/skills/pull-request-description.md

@@ -0,0 +1,48 @@
+# Pull Request Description
+
+## Overview
+
+When asked to create a pull request description, produce a fenced markdown code block (` ```markdown `) so the content can be copied and pasted directly into GitHub's PR body field without formatting being stripped.
+
+## Steps
+
+### 1. Identify the base branch
+
+Run `git log --oneline main..HEAD` to list all commits on the current branch since it diverged from `main`.
+
+### 2. Review what changed
+
+Run `git diff main...HEAD --stat` for a file-level summary, then `git diff main...HEAD` for the full diff. Focus on intent, not just mechanics.
+
+### 3. Produce a fenced markdown block
+
+Always wrap the output in a ` ```markdown ` code fence — never render it as plain markdown.
+
+## Format
+
+```markdown
+## Summary
+
+One or two sentences explaining what this PR does and why. No bullet points here — write it as prose.
+
+## Changes
+
+- **`FileOrComponentName`** — what changed and why
+- Keep each bullet to one line where possible
+
+## Testing
+
+- How the change was verified (unit tests, manual check, build passing, etc.)
+- Note any areas that couldn't be covered automatically
+
+## Notes
+
+Any caveats, follow-up tickets, or decisions worth flagging for reviewers (optional — omit if nothing to say).
+```
+
+## Notes
+
+- Only include sections that have content — omit empty headings (especially `Notes` if there's nothing to flag)
+- Lead with the user-facing or functional change; CSS/test/doc tidy-ups can be secondary bullets
+- Keep the tone factual — describe what changed, not the effort involved
+- Do not include "Co-Authored-By" or other git trailer lines — those belong in the commit message, not the PR body

.vscode/settings.json

@@ -36,12 +36,10 @@
       "editor.trimAutoWhitespace": "explicit"
     }
   },
-  // Use workspace TypeScript (5.9.x) instead of VS Code's built-in version
-  "typescript.tsdk": "node_modules/typescript/lib",
-
   // More info: https://open-props.style/#getting-started
   "cssvar.files": ["assets/styles/main.css"],
   "cssvar.ignore": [],
   "cssvar.extensions": ["css", "sss", "postcss", "vue", "ts"],
-  "js/ts.tsdk.path": "node_modules/typescript/lib"
+  "js/ts.tsdk.path": "node_modules/typescript/lib",
+  "git.addAICoAuthor": "off"
 }

Claude.md

@@ -301,6 +301,7 @@ See `.claude/skills/storybook-add-font.md` for the step-by-step process to add a
 8. **Incorrect type casting**: Use `as unknown as CustomType` for component instances
 9. **Unmocked browser APIs**: Always mock ResizeObserver, IntersectionObserver, etc.
 10. **Missing DOM element casting**: Cast to HTMLElement when accessing style properties
+11. **Sass-style BEM nesting in native CSS**: Never use `&__child` or `&-modifier` concatenation — this is Sass syntax and does not work in native CSS. esbuild silently converts `&__foo` to `:is(__foo)` which matches nothing. Use `& .block__child` (descendant selector) or a top-level `.block__child {}` rule instead. See `.claude/skills/css-nesting-conventions.md`.
 
 ## Development Workflow