fix: update sub-products in footer

static/js/main.js

@@ -9,6 +9,7 @@ const SELECTORS = {
   faqQuestion: '.faq-question',
   faqAnswer: '.faq-answer',
   fadeInElements: '.fade-in',
+  citationCopy: '.citation-copy',
 };
 
 function initNavbarScroll() {
@@ -190,6 +191,47 @@ function initReadMore() {
   });
 }
 
+function initCitationCopy() {
+  const copyButtons = document.querySelectorAll(SELECTORS.citationCopy);
+  if (!copyButtons.length) return;
+
+  copyButtons.forEach((btn) => {
+    const url = btn.getAttribute('data-citation-url');
+    const feedback = btn.querySelector('.citation-copy-feedback');
+    if (!url || !feedback) return;
+
+    let resetTimer = null;
+
+    btn.addEventListener('click', async () => {
+      clearTimeout(resetTimer);
+
+      try {
+        await navigator.clipboard.writeText(url);
+      } catch {
+        const textarea = document.createElement('textarea');
+        textarea.value = url;
+        textarea.setAttribute('readonly', '');
+        textarea.style.position = 'fixed';
+        textarea.style.left = '-9999px';
+        document.body.appendChild(textarea);
+        textarea.select();
+        document.execCommand('copy');
+        document.body.removeChild(textarea);
+      }
+
+      feedback.hidden = false;
+      btn.classList.add('is-copied');
+      btn.setAttribute('aria-label', 'Link copied');
+
+      resetTimer = setTimeout(() => {
+        feedback.hidden = true;
+        btn.classList.remove('is-copied');
+        btn.setAttribute('aria-label', 'Copy citation link');
+      }, 2000);
+    });
+  });
+}
+
 function init() {
   initNavbarScroll();
   initMobileMenu();
@@ -197,6 +239,7 @@ function init() {
   initFAQAccordion();
   initIntersectionObserver();
   initReadMore();
+  initCitationCopy();
 }
 
 if (document.readyState === 'loading') {