add accordion support

js/ui.js

@@ -0,0 +1,48 @@
+function activateSelfDeactivateSibs(button) {
+  if (button.classList.contains("active")) return;
+  
+  Array.from(button.parentNode.children).forEach(s => {
+    if (s === button){
+      button.classList.add('active');
+    } else {
+      s.classList.remove('active');
+    }
+    const targetId = s.dataset.targetId;
+    const target = document.getElementById(targetId);
+    
+    if (!target) return;
+    
+    if (s.classList.contains('active')) {
+      target.classList.add('active');
+      target.dispatchEvent(new CustomEvent("tab-activated", {bubbles: false}))
+    } else {
+      target.classList.remove('active');
+    }
+  });
+}
+
+document.addEventListener("DOMContentLoaded", () => {
+  // tabs
+  document.querySelectorAll(".tab-button").forEach(button => {
+    button.addEventListener("click", () => {
+      activateSelfDeactivateSibs(button);
+    });
+  });
+  
+  // accordions
+  const accordions = document.querySelectorAll(".accordion");
+  accordions.forEach(accordion => {
+    const header = accordion.querySelector(".accordion-header");
+    const toggleButton = header.querySelector(".accordion-toggle");
+    const content = accordion.querySelector(".accordion-content");
+    
+    const toggle = (e) => {
+      e.stopPropagation();
+      accordion.classList.toggle("hidden");
+      content.classList.toggle("hidden");
+      toggleButton.textContent = content.classList.contains("hidden") ? "►" : "▼"
+    }
+    
+    toggleButton.addEventListener("click", toggle);
+  });
+});