fix: viewer PDF (TOC, largeur) et plein ecran assistant (BUG-061 a BUG-063)

tests/frontend/ai.test.mjs

@@ -786,6 +786,29 @@ async function main() {
     panel.remove();
   });
 
+  // ── 10b. Fullscreen toggle must beat the persisted inline width ──
+  await test("fullscreen button toggles the panel and CSS lifts the inline width", async () => {
+    const { readFileSync } = await import("node:fs");
+    const css = readFileSync(path.resolve(JS_DIR, "..", "style.css"), "utf-8");
+    assert.match(
+      css,
+      /\.bookslm-panel\.fullscreen\s*\{\s*width:\s*100vw\s*!important;/,
+      "the fullscreen width must override the inline width written by the resize handle",
+    );
+
+    const b = new BooksLM();
+    const panel = b._render();
+    document.body.appendChild(panel);
+    const btn = panel.querySelector(".bookslm-btn-fullscreen");
+    btn.click();
+    assert.ok(panel.classList.contains("fullscreen"), "fullscreen class added on first click");
+    assert.equal(b._isFullscreen, true);
+    btn.click();
+    assert.ok(!panel.classList.contains("fullscreen"), "fullscreen class removed on second click");
+    assert.equal(b._isFullscreen, false);
+    panel.remove();
+  });
+
   // ── 11. Formatted markdown rendering ──
   await test("_renderMarkdown renders headings, lists, code and tables", () => {
     const b = new BooksLM();