feat(child-theme): scaffold asterion-bricks v0.1.0

Initial child theme structure inheriting from Bricks parent. Token-driven,
RGPD-native, mobile-first foundation ready for component and template work.

What's in this commit
- style.css: WP theme metadata (Template: bricks, v0.1.0)
- functions.php: enqueue cascade tokens -> utilities -> components,
  defer-loaded main.js, font preload, theme support, image sizes
  (av-hero 2400x1350, av-card 800x600, av-thumb 400x300), Gutenberg
  default styles dequeued
- theme.json: Gutenberg color/typo palette mirroring tokens
- assets/css/tokens.css: full design system per Design Handoff section 2
  (brand colors, neutrals, semantics, type scale + line-heights, 8pt
  spacing, radii, shadows, z-index, motion, prefers-reduced-motion)
- assets/css/utilities.css: modern reset + .av-container, .av-skip-link,
  .av-sr-only, .av-stack, .av-section helpers, opinionated heading scale
- assets/css/components.css: index of planned components + buttons
  (5 variants x 4 sizes per Design Handoff section 3.1) and links
- assets/js/main.js: vanilla skeleton with header scroll, IntersectionObserver
  reveal, count-up, mobile drawer; respects prefers-reduced-motion
- inc/cpt.php: register_post_type case_study (slug /customers/) + scenario
  (slug /scenarios/) + shared 'industry' taxonomy
- inc/seo.php: Organization JSON-LD on home; placeholders for Product,
  Article, FAQPage, BreadcrumbList
- assets/fonts/: Inter Variable + Italic WOFF2 self-hosted (RGPD; no
  Google Fonts CDN). Inter Display @font-face commented — Inter 4+ uses
  opsz axis from the same file.

Out of scope (intentionally deferred)
- Component fills: cards, forms, navigation, alerts, modals, tabs (placeholders)
- Page templates: home and beyond
- Bricks JSON template exports
- Schema.org Product / Article / FAQPage / BreadcrumbList implementations

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

wp-content/themes/asterion-bricks/assets/js/main.js

@@ -0,0 +1,149 @@
+/**
+ * Asterion Bricks — main JS
+ *
+ * Vanilla JS, defer-loaded. Wraps everything in DOMContentLoaded.
+ * Performance budget : initial bundle < 200 KB gzipped.
+ *
+ * Modules planned :
+ *   - Header scroll behavior (background swap after 80px)
+ *   - Mega menu trigger (hover desktop, click touch, ESC closes)
+ *   - Mobile drawer (full-screen overlay, accordion sections)
+ *   - Scroll-triggered fade-in (IntersectionObserver, threshold 0.15)
+ *   - Stat callouts count-up (1000ms ease-out)
+ *   - Hero video lazy-load + reduced-motion fallback to poster
+ */
+
+(function () {
+  'use strict';
+
+  /**
+   * Detect reduced motion once and expose a flag for downstream modules.
+   * Updated reactively if the user toggles the setting mid-session.
+   */
+  const reducedMotionQuery = window.matchMedia('(prefers-reduced-motion: reduce)');
+  let prefersReducedMotion = reducedMotionQuery.matches;
+  reducedMotionQuery.addEventListener('change', (e) => {
+    prefersReducedMotion = e.matches;
+  });
+
+  /**
+   * Header scroll behavior.
+   * After 80px scroll, header gets a `is-scrolled` class
+   * (consumed by .av-header.is-scrolled rule in components.css).
+   */
+  function initHeaderScroll() {
+    const header = document.querySelector('.av-header');
+    if (!header) return;
+
+    let ticking = false;
+    const onScroll = () => {
+      if (!ticking) {
+        window.requestAnimationFrame(() => {
+          header.classList.toggle('is-scrolled', window.scrollY > 80);
+          ticking = false;
+        });
+        ticking = true;
+      }
+    };
+    onScroll();
+    window.addEventListener('scroll', onScroll, { passive: true });
+  }
+
+  /**
+   * Scroll-triggered fade-in (Design Handoff section 5.3).
+   * Sections fade-in + slide-up 16px on entry, threshold 0.15, trigger once.
+   * Skipped entirely if user prefers reduced motion.
+   */
+  function initScrollReveal() {
+    if (prefersReducedMotion) return;
+
+    const targets = document.querySelectorAll('[data-av-reveal]');
+    if (!targets.length) return;
+
+    const observer = new IntersectionObserver((entries) => {
+      entries.forEach((entry) => {
+        if (entry.isIntersecting) {
+          entry.target.classList.add('is-revealed');
+          observer.unobserve(entry.target);
+        }
+      });
+    }, { threshold: 0.15, rootMargin: '0px 0px -10% 0px' });
+
+    targets.forEach((target) => observer.observe(target));
+  }
+
+  /**
+   * Stat count-up (Design Handoff section 5.3).
+   * Element : <span data-av-countup="0|target|duration">target</span>
+   * Animates from 0 to target value over duration ms, ease-out.
+   */
+  function initStatCountUp() {
+    if (prefersReducedMotion) return;
+
+    const stats = document.querySelectorAll('[data-av-countup]');
+    if (!stats.length) return;
+
+    const observer = new IntersectionObserver((entries) => {
+      entries.forEach((entry) => {
+        if (!entry.isIntersecting) return;
+        const el = entry.target;
+        const target = parseFloat(el.dataset.avCountup) || 0;
+        const duration = parseInt(el.dataset.avCountupDuration || '1000', 10);
+        const start = performance.now();
+
+        const tick = (now) => {
+          const elapsed = Math.min((now - start) / duration, 1);
+          // ease-out cubic
+          const eased = 1 - Math.pow(1 - elapsed, 3);
+          el.textContent = Math.round(target * eased).toLocaleString();
+          if (elapsed < 1) requestAnimationFrame(tick);
+        };
+        requestAnimationFrame(tick);
+        observer.unobserve(el);
+      });
+    }, { threshold: 0.5 });
+
+    stats.forEach((s) => observer.observe(s));
+  }
+
+  /**
+   * Mobile drawer toggle.
+   * Trigger : <button class="av-drawer-toggle" aria-controls="av-drawer">
+   * Drawer  : <div id="av-drawer" class="av-drawer">
+   */
+  function initMobileDrawer() {
+    const toggle = document.querySelector('.av-drawer-toggle');
+    const drawer = document.getElementById('av-drawer');
+    if (!toggle || !drawer) return;
+
+    const open = () => {
+      drawer.classList.add('is-open');
+      toggle.setAttribute('aria-expanded', 'true');
+      document.body.style.overflow = 'hidden';
+    };
+    const close = () => {
+      drawer.classList.remove('is-open');
+      toggle.setAttribute('aria-expanded', 'false');
+      document.body.style.overflow = '';
+    };
+
+    toggle.addEventListener('click', () => {
+      drawer.classList.contains('is-open') ? close() : open();
+    });
+
+    document.addEventListener('keydown', (e) => {
+      if (e.key === 'Escape' && drawer.classList.contains('is-open')) close();
+    });
+  }
+
+  /**
+   * Boot.
+   */
+  document.addEventListener('DOMContentLoaded', () => {
+    initHeaderScroll();
+    initScrollReveal();
+    initStatCountUp();
+    initMobileDrawer();
+  });
+
+})();