diff --git a/tests/test_palier12.py b/tests/test_palier12.py
index 314755c..6b81204 100644
--- a/tests/test_palier12.py
+++ b/tests/test_palier12.py
@@ -1,49 +1,76 @@
-"""Palier 12 (0.15.0): header unifié desktop/mobile (issue #16)."""
+"""Palier 12 (0.15.0 → refonte 0.16.0): layout barre latérale (#16)
+et wallboard sans défilement parasite."""
+
+import app.main as main
 
 
-def test_shared_header_on_app_pages(client, fake_gitea):
+def test_sidebar_on_app_pages(client, fake_gitea):
     for path in ("/", "/focus", "/today", "/briefing", "/forecast",
                  "/rules", "/health", "/standup", "/capture"):
         page = client.get(path)
         assert page.status_code == 200, path
-        assert page.text.count('id="nav-more-btn"') == 1, path
+        assert page.text.count('id="sidebar"') == 1, path
         assert page.text.count('id="nav-burger"') == 1, path
-        assert page.text.count('id="mobile-nav"') == 1, path
+        assert "with-sidebar" in page.text, path
         assert "/static/js/nav.js" in page.text, path
-        # Primaires visibles, secondaires dans le menu « Plus ».
-        assert 'href="/today"' in page.text
-        assert 'href="/health"' in page.text  # présent (menu Plus/mobile)
-        assert 'class="nav-pills main-nav"' in page.text
+        # Les quatre groupes de la barre latérale.
+        for group in ("Principal", "Rituels", "Pilotage", "Outils"):
+            assert group in page.text, (path, group)
+        assert 'href="/health"' in page.text
+        assert 'id="side-collapse"' in page.text
 
 
-def test_active_states(client, fake_gitea):
+def test_sidebar_active_states(client, fake_gitea):
     home = client.get("/")
-    assert 'href="/" class="nav-pill active"' in home.text
+    assert 'href="/" class="side-link active"' in home.text
     forecast = client.get("/forecast")
-    # La page active est dans « Plus » : bouton marqué + lien actif.
-    assert "active-soft" in forecast.text
-    assert 'href="/forecast" class="nav-pill active"' in forecast.text
+    assert 'href="/forecast" class="side-link active"' in forecast.text
     today = client.get("/today")
-    assert 'href="/today" class="nav-pill active"' in today.text
+    assert 'href="/today" class="side-link active"' in today.text
 
 
-def test_board_header_crumb_and_gitea_link(client, fake_gitea):
+def test_board_topbar_crumb_and_gitea_link(client, fake_gitea):
     board = client.get("/board/Projets/demo")
     assert board.status_code == 200
-    assert 'href="/board/Projets/demo"' in board.text  # fil d'Ariane
+    assert 'href="/board/Projets/demo"' in board.text  # fil d'Ariane topbar
     assert "Gitea ↗" in board.text
-    assert 'id="nav-burger"' in board.text
+    assert 'id="sidebar"' in board.text
 
 
-def test_wall_has_no_app_header(client, fake_gitea):
+def test_wall_has_no_sidebar(client, fake_gitea):
     wall = client.get("/wall")
     assert wall.status_code == 200
-    assert 'id="nav-burger"' not in wall.text  # plein écran TV assumé
+    assert 'id="sidebar"' not in wall.text  # plein écran TV assumé
+    assert "wall-foot" in wall.text
 
 
 def test_nav_js_contract(client, fake_gitea):
     js = client.get("/static/js/nav.js")
     assert js.status_code == 200
-    assert "nav-burger" in js.text
+    assert "sidebar-collapsed" in js.text
+    assert "localStorage" in js.text
+    assert "side-backdrop" in js.text
     assert "Escape" in js.text
-    assert "aria-expanded" in js.text
+
+
+def test_wall_more_cards_line(client, fake_gitea, monkeypatch):
+    async def fake_collect(only_repo):
+        return [{
+            "full_name": "Projets/demo",
+            "counts": {c: 0 for c in
+                       ("backlog", "todo", "in_progress", "qa", "review", "done")},
+            "open_total": 12,
+            "cards": [
+                {"number": i, "title": f"Carte {i}", "column": "in_progress",
+                 "column_label": "🚧 En cours", "age_days": 2, "aging": False}
+                for i in range(1, 10)
+            ],
+            "cards_total": 12,
+            "closed_today": 1,
+        }]
+
+    monkeypatch.setattr(main, "_collect_wall_data", fake_collect)
+    page = client.get("/wall")
+    assert page.status_code == 200
+    assert "+3 autres cartes en vol" in page.text
+    assert "📋 Ouvertes" in page.text