docs: guide d'utilisation enrichi + navigation clavier — sections Tabs, Édition, Graphe, Palette, Partage, Sauvegardes, Sécurité

frontend/js/config.js

@@ -214,6 +214,7 @@ function initHelpNavigation() {
   const helpContent = document.querySelector(".help-content");
   const helpBody = document.getElementById("help-body");
   const navLinks = document.querySelectorAll(".help-nav-link");
+  const navList = document.querySelector(".help-nav-list");
 
   if (!helpContent || !helpBody || !navLinks.length) return;
 
@@ -225,11 +226,63 @@ function initHelpNavigation() {
       const targetSection = document.getElementById(targetId);
       if (targetSection) {
         targetSection.scrollIntoView({ behavior: "smooth", block: "start" });
+        // Focus the section for accessibility
+        targetSection.setAttribute("tabindex", "-1");
+        targetSection.focus({ preventScroll: true });
       }
     });
   });
 
-  // Scroll spy - update active nav link based on scroll position
+  // ── Keyboard navigation inside nav list ──
+  if (navList) {
+    navList.addEventListener("keydown", (e) => {
+      const items = [...navList.querySelectorAll(".help-nav-link")];
+      const currentIdx = items.indexOf(document.activeElement);
+
+      if (e.key === "ArrowDown" || e.key === "ArrowRight") {
+        e.preventDefault();
+        const next = (currentIdx + 1) % items.length;
+        items[next].focus();
+      } else if (e.key === "ArrowUp" || e.key === "ArrowLeft") {
+        e.preventDefault();
+        const prev = (currentIdx - 1 + items.length) % items.length;
+        items[prev].focus();
+      } else if (e.key === "Home") {
+        e.preventDefault();
+        items[0].focus();
+      } else if (e.key === "End") {
+        e.preventDefault();
+        items[items.length - 1].focus();
+      }
+    });
+
+    // Make nav items focusable
+    navList.querySelectorAll("li").forEach((li) => {
+      li.setAttribute("role", "none"); // remove listitem role for cleaner a11y
+    });
+  }
+
+  // ── Keyboard: Ctrl+↑/↓ inside help body to jump between sections ──
+  helpBody.addEventListener("keydown", (e) => {
+    if ((e.ctrlKey || e.metaKey) && (e.key === "ArrowDown" || e.key === "ArrowUp")) {
+      e.preventDefault();
+      const sections = [...document.querySelectorAll(".help-section")];
+      const currentSection = sections.find((s) => {
+        const rect = s.getBoundingClientRect();
+        return rect.top >= 0 && rect.top < 100;
+      });
+      if (!currentSection) return;
+
+      const currentIdx = sections.indexOf(currentSection);
+      if (e.key === "ArrowDown" && currentIdx < sections.length - 1) {
+        sections[currentIdx + 1].scrollIntoView({ behavior: "smooth", block: "start" });
+      } else if (e.key === "ArrowUp" && currentIdx > 0) {
+        sections[currentIdx - 1].scrollIntoView({ behavior: "smooth", block: "start" });
+      }
+    }
+  });
+
+  // ── Scroll spy ──
   const observer = new IntersectionObserver(
     (entries) => {
       entries.forEach((entry) => {