diff --git a/index.css b/index.css
index 8d1b543..e8c7259 100644
--- a/index.css
+++ b/index.css
@@ -209,3 +209,26 @@ body {
 /* Hide scrollbars on horizontal lists where we still want scrolling */
 .no-scrollbar::-webkit-scrollbar { display: none; }
 .no-scrollbar { -ms-overflow-style: none; scrollbar-width: none; }
+
+/* --- Sidebar: scrollbar visible au survol / focus uniquement --------------- */
+.sidebar-scroll {
+  overflow-y: hidden;
+  scrollbar-width: thin;
+  scrollbar-color: #334155 transparent;
+  scrollbar-gutter: stable;
+}
+.sidebar-scroll:hover,
+.sidebar-scroll:focus,
+.sidebar-scroll:focus-within {
+  overflow-y: auto;
+}
+.sidebar-scroll::-webkit-scrollbar { width: 6px; }
+.sidebar-scroll::-webkit-scrollbar-track { background: transparent; }
+.sidebar-scroll::-webkit-scrollbar-thumb { background: #334155; border-radius: 9999px; }
+@media (hover: none) {
+  /* tactile / mobile : toujours scrollable */
+  .sidebar-scroll { overflow-y: auto; }
+}
+@media (prefers-reduced-motion: reduce) {
+  .sidebar-scroll { scroll-behavior: auto; }
+}
diff --git a/src/components/sidebar/sidebar.component.html b/src/components/sidebar/sidebar.component.html
index 5f98d90..8f360a3 100644
--- a/src/components/sidebar/sidebar.component.html
+++ b/src/components/sidebar/sidebar.component.html
@@ -1,4 +1,4 @@
-<nav class="h-full w-full bg-slate-900 md:bg-transparent text-slate-200 p-3 md:p-0 overflow-y-auto">
+<nav tabindex="0" class="sidebar-scroll h-full w-full bg-slate-900 md:bg-transparent text-slate-200 p-3 md:p-0">
   <div class="space-y-6">
     <!-- Brand (small only) -->
     <div class="md:hidden flex items-center gap-2 px-3 py-2">
@@ -6,7 +6,7 @@
       <span class="text-xl font-bold">NewTube</span>
     </div>
 
-    <!-- Main -->
+    <!-- Main : toujours visible, hors accordeon -->
     <div>
       <ul class="space-y-1">
         <li>
@@ -33,161 +33,194 @@
     <!-- Vous -->
     @if (isLoggedIn()) {
       <div>
-        <div class="px-3 py-2 text-xs uppercase tracking-wide text-slate-400" [class.hidden]="collapsed">{{ 'nav.you' | t }}</div>
-        <ul class="space-y-1">
-          <li>
-            <a routerLink="/library/subscriptions" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.subscriptions' | t) : null">
-              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M4 4h16a2 2 0 0 1 2 2v12a2 2 0 0 1-2 2H4a2 2 0 0 1-2-2V6a2 2 0 0 1 2-2zm0 2v12h16V6H4zm3 3h10v2H7V9zm0 4h7v2H7v-2z"/></svg>
-              <span [class.hidden]="collapsed">{{ 'nav.subscriptions' | t }}</span>
-            </a>
-          </li>
-          <li>
-            <a routerLink="/account/history" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.history' | t) : null">
-              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 8a1 1 0 0 1 1 1v3.38l2.32 1.34a1 1 0 1 1-1 1.74l-2.82-1.63A1 1 0 0 1 11 13V9a1 1 0 0 1 1-1zm0-6a10 10 0 1 0 10 10 10.011 10.011 0 0 0-10-10z"/></svg>
-              <span [class.hidden]="collapsed">{{ 'nav.history' | t }}</span>
-            </a>
-          </li>
-          <li>
-            <a routerLink="/library/liked" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.liked' | t) : null">
-              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 21s-6.716-4.248-9.193-6.725A6 6 0 0 1 12 5.414 6 6 0 0 1 21.193 14.275C18.716 16.752 12 21 12 21z"/></svg>
-              <span [class.hidden]="collapsed">{{ 'nav.liked' | t }}</span>
-            </a>
-          </li>
-          <li>
-            <a routerLink="/library/downloads" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.downloads' | t) : null">
-              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 3v10.17l3.59-3.58L17 11l-5 5-5-5 1.41-1.41L12 13.17V3h0zm-7 15h14v2H5v-2z"/></svg>
-              <span [class.hidden]="collapsed">{{ 'nav.downloads' | t }}</span>
-            </a>
-          </li>
-        </ul>
+        <button type="button" (click)="toggleSection('you')" [attr.aria-expanded]="isOpen('you')" aria-controls="sidebar-section-you" class="flex w-full items-center justify-between px-3 py-2 text-xs uppercase tracking-wide text-slate-400 hover:text-slate-200 transition" [class.hidden]="collapsed">
+          <span>{{ 'nav.you' | t }}</span>
+          <svg xmlns="http://www.w3.org/2000/svg" class="h-4 w-4 transition-transform" [class.rotate-180]="isOpen('you')" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true"><path d="M7 10l5 5 5-5z"/></svg>
+        </button>
+        <div id="sidebar-section-you" [hidden]="!collapsed && !isOpen('you')">
+          <ul class="space-y-1">
+            <li>
+              <a routerLink="/library/subscriptions" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.subscriptions' | t) : null">
+                <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M4 4h16a2 2 0 0 1 2 2v12a2 2 0 0 1-2 2H4a2 2 0 0 1-2-2V6a2 2 0 0 1 2-2zm0 2v12h16V6H4zm3 3h10v2H7V9zm0 4h7v2H7v-2z"/></svg>
+                <span [class.hidden]="collapsed">{{ 'nav.subscriptions' | t }}</span>
+              </a>
+            </li>
+            <li>
+              <a routerLink="/account/history" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.history' | t) : null">
+                <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 8a1 1 0 0 1 1 1v3.38l2.32 1.34a1 1 0 1 1-1 1.74l-2.82-1.63A1 1 0 0 1 11 13V9a1 1 0 0 1 1-1zm0-6a10 10 0 1 0 10 10 10.011 10.011 0 0 0-10-10z"/></svg>
+                <span [class.hidden]="collapsed">{{ 'nav.history' | t }}</span>
+              </a>
+            </li>
+            <li>
+              <a routerLink="/library/liked" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.liked' | t) : null">
+                <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 21s-6.716-4.248-9.193-6.725A6 6 0 0 1 12 5.414 6 6 0 0 1 21.193 14.275C18.716 16.752 12 21 12 21z"/></svg>
+                <span [class.hidden]="collapsed">{{ 'nav.liked' | t }}</span>
+              </a>
+            </li>
+            <li>
+              <a routerLink="/library/downloads" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.downloads' | t) : null">
+                <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 3v10.17l3.59-3.58L17 11l-5 5-5-5 1.41-1.41L12 13.17V3h0zm-7 15h14v2H5v-2z"/></svg>
+                <span [class.hidden]="collapsed">{{ 'nav.downloads' | t }}</span>
+              </a>
+            </li>
+          </ul>
+        </div>
       </div>
 
       <!-- Groupes d'abonnements (façon PocketTube) -->
       <div *ngIf="!collapsed && subscriptionGroups().length > 0">
-        <div class="px-3 py-2 text-xs uppercase tracking-wide text-slate-400">{{ 'nav.groups' | t : 'Groupes' }}</div>
-        <ul class="space-y-1">
-          <li *ngFor="let group of subscriptionGroups()">
-            <a [routerLink]="['/library/subscriptions']" [queryParams]="{ group: group.id, tab: 'channels' }" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition gap-3">
-              <span class="flex h-6 w-6 items-center justify-center rounded text-base" [style.background-color]="group.color + '26'">{{ group.icon }}</span>
-              <span class="flex-1 truncate text-sm">{{ group.name }}</span>
-              <span class="text-xs text-slate-500">{{ group.channelCount }}</span>
-            </a>
-          </li>
-        </ul>
+        <button type="button" (click)="toggleSection('groups')" [attr.aria-expanded]="isOpen('groups')" aria-controls="sidebar-section-groups" class="flex w-full items-center justify-between px-3 py-2 text-xs uppercase tracking-wide text-slate-400 hover:text-slate-200 transition">
+          <span>{{ 'nav.groups' | t }} <span class="text-slate-500">({{ subscriptionGroups().length }})</span></span>
+          <svg xmlns="http://www.w3.org/2000/svg" class="h-4 w-4 transition-transform" [class.rotate-180]="isOpen('groups')" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true"><path d="M7 10l5 5 5-5z"/></svg>
+        </button>
+        <div id="sidebar-section-groups" [hidden]="!isOpen('groups')">
+          <ul class="space-y-1">
+            <li *ngFor="let group of displayedGroups()">
+              <a [routerLink]="['/library/subscriptions']" [queryParams]="{ group: group.id, tab: 'channels' }" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition gap-3">
+                <span class="flex h-6 w-6 items-center justify-center rounded text-base" [style.background-color]="group.color + '26'">{{ group.icon }}</span>
+                <span class="flex-1 truncate text-sm">{{ group.name }}</span>
+                <span class="text-xs text-slate-500">{{ group.channelCount }}</span>
+              </a>
+            </li>
+          </ul>
+          <button *ngIf="subscriptionGroups().length > 5" type="button" class="flex items-center gap-2 px-3 py-2 text-sm text-slate-300 hover:text-white" (click)="toggleGroups()">
+            <svg xmlns="http://www.w3.org/2000/svg" class="h-5 w-5 transition-transform" [class.rotate-180]="showAllGroups()" viewBox="0 0 24 24" fill="currentColor"><path d="M7 10l5 5 5-5z"/></svg>
+            <span>{{ showAllGroups() ? ('common.less' | t) : ('common.more' | t) }}</span>
+          </button>
+        </div>
       </div>
     }
 
     <!-- Fournisseurs -->
     <div>
-      <div class="px-3 py-2 text-xs uppercase tracking-wide text-slate-400" [class.hidden]="collapsed">Fournisseurs</div>
-      <ul class="space-y-1">
-        <!-- All providers except PeerTube (order handled in TS so PT is last) -->
-        <ng-container *ngFor="let p of providersList()">
-          <li *ngIf="p.id !== 'peertube'">
-            <a [routerLink]="['/p', p.id, 't', 'trending']" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (p.label) : null">
-              <span class="h-6 w-6 flex items-center justify-center">
-                <ng-container [ngSwitch]="p.id">
-                  <!-- YouTube -->
-                  <svg *ngSwitchCase="'youtube'" class="h-5 w-5" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
-                    <rect x="3" y="6" width="18" height="12" rx="3" class="text-red-600" fill="currentColor"/>
-                    <polygon points="10,9 16,12 10,15" fill="white"/>
-                  </svg>
-                  <!-- Dailymotion -->
-                  <svg *ngSwitchCase="'dailymotion'" class="h-5 w-5 text-blue-500" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
-                    <circle cx="12" cy="12" r="10" fill="currentColor"/>
-                    <polygon points="11,8 16,12 11,16" fill="white"/>
-                  </svg>
-                  <!-- Twitch -->
-                  <svg *ngSwitchCase="'twitch'" class="h-5 w-5 text-purple-500" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
-                    <path d="M4 3h16v11l-4 4h-3l-2 2H9v-2H6V3zm3 2v9h6l2-2h3V5H7z" fill="currentColor"/>
-                  </svg>
-                  <!-- Rumble -->
-                  <svg *ngSwitchCase="'rumble'" class="h-5 w-5 text-green-500" viewBox="0 0 24 24" aria-hidden="true">
-                    <circle cx="12" cy="12" r="10" fill="currentColor"/>
-                    <polygon points="10,8 16,12 10,16" fill="white"/>
-                  </svg>
-                  <!-- Odysee -->
-                  <svg *ngSwitchCase="'odysee'" class="h-5 w-5 text-pink-500" viewBox="0 0 24 24" aria-hidden="true">
-                    <circle cx="12" cy="12" r="10" fill="currentColor"/>
-                    <circle cx="12" cy="12" r="5" fill="white"/>
-                  </svg>
-                  <!-- Fallback generic play icon -->
-                  <svg *ngSwitchDefault class="h-5 w-5 text-slate-300" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
-                    <polygon points="9,7 17,12 9,17" fill="currentColor"/>
-                  </svg>
-                </ng-container>
-              </span>
-              <span [class.hidden]="collapsed">{{ p.label }}</span>
-            </a>
-          </li>
-        </ng-container>
+      <button type="button" (click)="toggleSection('providers')" [attr.aria-expanded]="isOpen('providers')" aria-controls="sidebar-section-providers" class="flex w-full items-center justify-between px-3 py-2 text-xs uppercase tracking-wide text-slate-400 hover:text-slate-200 transition" [class.hidden]="collapsed">
+        <span>{{ 'nav.providers' | t }} <span class="text-slate-500">({{ providersList().length }})</span></span>
+        <svg xmlns="http://www.w3.org/2000/svg" class="h-4 w-4 transition-transform" [class.rotate-180]="isOpen('providers')" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true"><path d="M7 10l5 5 5-5z"/></svg>
+      </button>
+      <div id="sidebar-section-providers" [hidden]="!collapsed && !isOpen('providers')">
+        <ul class="space-y-1">
+          <!-- All providers except PeerTube (order handled in TS so PT is last) -->
+          <ng-container *ngFor="let p of providersList()">
+            <li *ngIf="p.id !== 'peertube'">
+              <a [routerLink]="['/p', p.id, 't', 'trending']" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (p.label) : null">
+                <span class="h-6 w-6 flex items-center justify-center">
+                  <ng-container [ngSwitch]="p.id">
+                    <!-- YouTube -->
+                    <svg *ngSwitchCase="'youtube'" class="h-5 w-5" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
+                      <rect x="3" y="6" width="18" height="12" rx="3" class="text-red-600" fill="currentColor"/>
+                      <polygon points="10,9 16,12 10,15" fill="white"/>
+                    </svg>
+                    <!-- Dailymotion -->
+                    <svg *ngSwitchCase="'dailymotion'" class="h-5 w-5 text-blue-500" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
+                      <circle cx="12" cy="12" r="10" fill="currentColor"/>
+                      <polygon points="11,8 16,12 11,16" fill="white"/>
+                    </svg>
+                    <!-- Twitch -->
+                    <svg *ngSwitchCase="'twitch'" class="h-5 w-5 text-purple-500" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
+                      <path d="M4 3h16v11l-4 4h-3l-2 2H9v-2H6V3zm3 2v9h6l2-2h3V5H7z" fill="currentColor"/>
+                    </svg>
+                    <!-- Rumble -->
+                    <svg *ngSwitchCase="'rumble'" class="h-5 w-5 text-green-500" viewBox="0 0 24 24" aria-hidden="true">
+                      <circle cx="12" cy="12" r="10" fill="currentColor"/>
+                      <polygon points="10,8 16,12 10,16" fill="white"/>
+                    </svg>
+                    <!-- Odysee -->
+                    <svg *ngSwitchCase="'odysee'" class="h-5 w-5 text-pink-500" viewBox="0 0 24 24" aria-hidden="true">
+                      <circle cx="12" cy="12" r="10" fill="currentColor"/>
+                      <circle cx="12" cy="12" r="5" fill="white"/>
+                    </svg>
+                    <!-- Fallback generic play icon -->
+                    <svg *ngSwitchDefault class="h-5 w-5 text-slate-300" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
+                      <polygon points="9,7 17,12 9,17" fill="currentColor"/>
+                    </svg>
+                  </ng-container>
+                </span>
+                <span [class.hidden]="collapsed">{{ p.label }}</span>
+              </a>
+            </li>
+          </ng-container>
 
-        <!-- PeerTube group with instances as sub-items -->
-        <ng-container *ngFor="let p of providersList()">
-          <li [ngClass]="{ 'mt-2': true }" *ngIf="p.id === 'peertube'">
-            <a [routerLink]="['/p', 'peertube', 't', 'trending']" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (p.label) : null">
-              <span class="h-6 w-6 flex items-center justify-center">
-                <!-- PeerTube logo style (orange play) -->
-                <svg class="h-5 w-5 text-orange-500" viewBox="0 0 24 24" aria-hidden="true">
-                  <circle cx="12" cy="12" r="10" fill="currentColor"/>
-                  <polygon points="10,8 16,12 10,16" fill="white"/>
-                </svg>
-              </span>
-              <span [class.hidden]="collapsed">{{ p.label }}</span>
-            </a>
-            <!-- Sub-list of instances (visible when not collapsed) -->
-            <ul class="ml-8 mt-1 space-y-1" [class.hidden]="collapsed">
-              <li *ngFor="let inst of peerTubeInstances()">
-                <a [routerLink]="['/p', 'peertube', 't', 'trending']"
-                   (click)="$event.preventDefault(); selectPeerTubeInstance(inst)"
-                   class="flex items-center px-3 py-1.5 rounded hover:bg-slate-800 transition gap-2">
-                  <svg class="h-4 w-4 text-orange-500" viewBox="0 0 24 24" aria-hidden="true">
+          <!-- PeerTube group with instances as sub-items -->
+          <ng-container *ngFor="let p of providersList()">
+            <li [ngClass]="{ 'mt-2': true }" *ngIf="p.id === 'peertube'">
+              <a [routerLink]="['/p', 'peertube', 't', 'trending']" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (p.label) : null">
+                <span class="h-6 w-6 flex items-center justify-center">
+                  <!-- PeerTube logo style (orange play) -->
+                  <svg class="h-5 w-5 text-orange-500" viewBox="0 0 24 24" aria-hidden="true">
                     <circle cx="12" cy="12" r="10" fill="currentColor"/>
                     <polygon points="10,8 16,12 10,16" fill="white"/>
                   </svg>
-                  <span class="text-xs" [ngClass]="{ 'text-sky-400': inst === activePeerTubeInstance(), 'text-slate-300': inst !== activePeerTubeInstance() }">{{ inst }}</span>
-                </a>
-              </li>
-            </ul>
-          </li>
-        </ng-container>
-      </ul>
+                </span>
+                <span [class.hidden]="collapsed">{{ p.label }}</span>
+              </a>
+              <!-- Sub-list of instances (visible when not collapsed) -->
+              <ul class="ml-8 mt-1 space-y-1" [class.hidden]="collapsed">
+                <li *ngFor="let inst of displayedInstances()">
+                  <a [routerLink]="['/p', 'peertube', 't', 'trending']"
+                     (click)="$event.preventDefault(); selectPeerTubeInstance(inst)"
+                     class="flex items-center px-3 py-1.5 rounded hover:bg-slate-800 transition gap-2">
+                    <svg class="h-4 w-4 text-orange-500" viewBox="0 0 24 24" aria-hidden="true">
+                      <circle cx="12" cy="12" r="10" fill="currentColor"/>
+                      <polygon points="10,8 16,12 10,16" fill="white"/>
+                    </svg>
+                    <span class="text-xs" [ngClass]="{ 'text-sky-400': inst === activePeerTubeInstance(), 'text-slate-300': inst !== activePeerTubeInstance() }">{{ inst }}</span>
+                  </a>
+                </li>
+              </ul>
+              <button *ngIf="!collapsed && peerTubeInstances().length > 3" type="button" class="ml-8 flex items-center gap-2 px-3 py-2 text-sm text-slate-300 hover:text-white" (click)="toggleInstances()">
+                <svg xmlns="http://www.w3.org/2000/svg" class="h-5 w-5 transition-transform" [class.rotate-180]="showAllInstances()" viewBox="0 0 24 24" fill="currentColor"><path d="M7 10l5 5 5-5z"/></svg>
+                <span>{{ showAllInstances() ? ('common.less' | t) : ('common.more' | t) }}</span>
+              </button>
+            </li>
+          </ng-container>
+        </ul>
+      </div>
     </div>
 
     <!-- Explorer (themes list with more/less) -->
     <div>
-      <div class="px-3 py-2 text-xs uppercase tracking-wide text-slate-400" [class.hidden]="collapsed">{{ 'nav.explore' | t }}</div>
-      <ul class="space-y-1">
-        <li *ngFor="let t of displayedThemes()">
-          <a [routerLink]="['/t', t.slug]" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (t.label) : null">
-            <span class="h-6 w-6 flex items-center justify-center text-lg">{{ t.emoji }}</span>
-            <span [class.hidden]="collapsed">{{ t.label }}</span>
-          </a>
-        </li>
-      </ul>
-      <button class="flex items-center gap-2 px-3 py-2 text-sm text-slate-300 hover:text-white" (click)="toggleThemes()" [class.hidden]="collapsed">
-        <svg xmlns="http://www.w3.org/2000/svg" class="h-5 w-5" viewBox="0 0 24 24" fill="currentColor"><path d="M12 5l7 7-7 7-1.41-1.41L15.17 13H5v-2h10.17l-4.58-4.59L12 5z"/></svg>
-        <span>{{ showAllThemes() ? ('common.less' | t) : ('common.more' | t) }}</span>
+      <button type="button" (click)="toggleSection('explore')" [attr.aria-expanded]="isOpen('explore')" aria-controls="sidebar-section-explore" class="flex w-full items-center justify-between px-3 py-2 text-xs uppercase tracking-wide text-slate-400 hover:text-slate-200 transition" [class.hidden]="collapsed">
+        <span>{{ 'nav.explore' | t }} <span class="text-slate-500">({{ themes.themes().length }})</span></span>
+        <svg xmlns="http://www.w3.org/2000/svg" class="h-4 w-4 transition-transform" [class.rotate-180]="isOpen('explore')" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true"><path d="M7 10l5 5 5-5z"/></svg>
       </button>
+      <div id="sidebar-section-explore" [hidden]="!collapsed && !isOpen('explore')">
+        <ul class="space-y-1">
+          <li *ngFor="let t of displayedThemes()">
+            <a [routerLink]="['/t', t.slug]" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? (t.label) : null">
+              <span class="h-6 w-6 flex items-center justify-center text-lg">{{ t.emoji }}</span>
+              <span [class.hidden]="collapsed">{{ t.label }}</span>
+            </a>
+          </li>
+        </ul>
+        <button type="button" class="flex items-center gap-2 px-3 py-2 text-sm text-slate-300 hover:text-white" (click)="toggleThemes()" [class.hidden]="collapsed">
+          <svg xmlns="http://www.w3.org/2000/svg" class="h-5 w-5 transition-transform" [class.rotate-180]="showAllThemes()" viewBox="0 0 24 24" fill="currentColor"><path d="M7 10l5 5 5-5z"/></svg>
+          <span>{{ showAllThemes() ? ('common.less' | t) : ('common.more' | t) }}</span>
+        </button>
+      </div>
     </div>
 
     <!-- Informations -->
     <div>
-      <div class="px-3 py-2 text-xs uppercase tracking-wide text-slate-400" [class.hidden]="collapsed">{{ 'nav.info' | t : 'Informations' }}</div>
-      <ul class="space-y-1">
-        <li>
-          <a routerLink="/info/utilisation" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.usage' | t : 'Utilisation') : null">
-            <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 2a10 10 0 1 0 10 10A10.011 10.011 0 0 0 12 2zm1 15h-2v-6h2zm0-8h-2V7h2z"/></svg>
-            <span [class.hidden]="collapsed">{{ 'nav.usage' | t : 'Utilisation' }}</span>
-          </a>
-        </li>
-        <li>
-          <a href="https://git.dracodev.net/Projets/NewTube" target="_blank" rel="noopener noreferrer" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? 'Gitea' : null">
-            <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 2a10 10 0 1 0 10 10A10.011 10.011 0 0 0 12 2zm1 14.59V20h-2v-3.41a4.994 4.994 0 0 1-4-4.9V7h2v4.69A3 3 0 0 0 12 14a3 3 0 0 0 3-2.31V7h2v4.69a4.994 4.994 0 0 1-4 4.9z"/></svg>
-            <span [class.hidden]="collapsed">Gitea</span>
-          </a>
-        </li>
-      </ul>
+      <button type="button" (click)="toggleSection('info')" [attr.aria-expanded]="isOpen('info')" aria-controls="sidebar-section-info" class="flex w-full items-center justify-between px-3 py-2 text-xs uppercase tracking-wide text-slate-400 hover:text-slate-200 transition" [class.hidden]="collapsed">
+        <span>{{ 'nav.info' | t }}</span>
+        <svg xmlns="http://www.w3.org/2000/svg" class="h-4 w-4 transition-transform" [class.rotate-180]="isOpen('info')" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true"><path d="M7 10l5 5 5-5z"/></svg>
+      </button>
+      <div id="sidebar-section-info" [hidden]="!collapsed && !isOpen('info')">
+        <ul class="space-y-1">
+          <li>
+            <a routerLink="/info/utilisation" routerLinkActive="bg-slate-800" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? ('nav.usage' | t) : null">
+              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 2a10 10 0 1 0 10 10A10.011 10.011 0 0 0 12 2zm1 15h-2v-6h2zm0-8h-2V7h2z"/></svg>
+              <span [class.hidden]="collapsed">{{ 'nav.usage' | t }}</span>
+            </a>
+          </li>
+          <li>
+            <a href="https://git.dracodev.net/Projets/NewTube" target="_blank" rel="noopener noreferrer" class="flex items-center px-3 py-2 rounded hover:bg-slate-800 transition" [ngClass]="{ 'gap-0 justify-center': collapsed, 'gap-3': !collapsed }" [attr.title]="collapsed ? 'Gitea' : null">
+              <svg xmlns="http://www.w3.org/2000/svg" class="h-6 w-6" viewBox="0 0 24 24" fill="currentColor"><path d="M12 2a10 10 0 1 0 10 10A10.011 10.011 0 0 0 12 2zm1 14.59V20h-2v-3.41a4.994 4.994 0 0 1-4-4.9V7h2v4.69A3 3 0 0 0 12 14a3 3 0 0 0 3-2.31V7h2v4.69a4.994 4.994 0 0 1-4 4.9z"/></svg>
+              <span [class.hidden]="collapsed">Gitea</span>
+            </a>
+          </li>
+        </ul>
+      </div>
     </div>
   </div>
 </nav>
diff --git a/src/components/sidebar/sidebar.component.ts b/src/components/sidebar/sidebar.component.ts
index 9073122..d7d6cfd 100644
--- a/src/components/sidebar/sidebar.component.ts
+++ b/src/components/sidebar/sidebar.component.ts
@@ -1,12 +1,14 @@
-import { ChangeDetectionStrategy, Component, computed, effect, inject, Input } from '@angular/core';
+import { ChangeDetectionStrategy, Component, computed, effect, inject, Input, signal } from '@angular/core';
 import { CommonModule } from '@angular/common';
-import { RouterLink, RouterLinkActive } from '@angular/router';
+import { NavigationEnd, Router, RouterLink, RouterLinkActive } from '@angular/router';
 import { InstanceService } from '../../services/instance.service';
 import { ThemesService } from '../../services/themes.service';
 import { AuthService } from '../../services/auth.service';
 import { SubscriptionsService } from '../../services/subscriptions.service';
 import { TranslatePipe } from '../../pipes/translate.pipe';
 
+export type SidebarSectionId = 'you' | 'groups' | 'providers' | 'explore' | 'info';
+
 @Component({
   selector: 'app-sidebar',
   standalone: true,
@@ -18,6 +20,7 @@ export class SidebarComponent {
   private instances = inject(InstanceService);
   private auth = inject(AuthService);
   private subs = inject(SubscriptionsService);
+  private router = inject(Router, { optional: true });
   themes = inject(ThemesService);
 
   // Check if user is logged in
@@ -30,6 +33,13 @@ export class SidebarComponent {
         this.subs.listGroups().subscribe();
       }
     });
+    // Auto-ouvre la section contenant la route active (accordeon unique strict).
+    try {
+      this.openFromUrl(this.router?.url, false);
+      this.router?.events.subscribe(e => {
+        if (e instanceof NavigationEnd) this.openFromUrl(e.urlAfterRedirects || e.url, true);
+      });
+    } catch {}
   }
 
   provider = computed(() => this.instances.selectedProvider());
@@ -47,6 +57,69 @@ export class SidebarComponent {
   displayedThemes = computed(() => this.showAllThemes() ? this.themes.themes() : this.themes.themes().slice(0, 8));
   toggleThemes() { this.themes.toggleShowAll(); }
 
+  // --- Accordeon unique strict (une seule section ouverte a la fois) ---
+  private static readonly OPEN_SECTION_KEY = 'newtube.sidebar.openSection';
+  private static readonly GROUP_LIMIT = 5;
+  private static readonly INSTANCE_LIMIT = 3;
+
+  openSection = signal<SidebarSectionId | null>((() => {
+    try {
+      const raw = localStorage.getItem(SidebarComponent.OPEN_SECTION_KEY) as SidebarSectionId | null;
+      if (raw === 'you' || raw === 'groups' || raw === 'providers' || raw === 'explore' || raw === 'info') return raw;
+    } catch {}
+    return 'providers';
+  })());
+
+  isOpen(id: SidebarSectionId): boolean {
+    return this.openSection() === id;
+  }
+
+  toggleSection(id: SidebarSectionId): void {
+    const next = this.openSection() === id ? null : id;
+    this.openSection.set(next);
+    try {
+      if (next) localStorage.setItem(SidebarComponent.OPEN_SECTION_KEY, next);
+      else localStorage.removeItem(SidebarComponent.OPEN_SECTION_KEY);
+    } catch {}
+  }
+
+  /** Ouvre automatiquement la section contenant la route active.
+      Routes non mappees (/shorts, /watch, /search...) : ne touche a rien,
+      le choix manuel persiste s'applique. */
+  private openFromUrl(url: string | undefined, persist = true): void {
+    if (!url) return;
+    const pathOnly = url.split('?')[0].split('#')[0] || '/';
+    let next: SidebarSectionId | null = null;
+    if (pathOnly.startsWith('/library/subscriptions') && url.includes('group')) next = 'groups';
+    else if (pathOnly.startsWith('/library') || pathOnly.startsWith('/account')) next = 'you';
+    else if (pathOnly.startsWith('/p/')) next = 'providers';
+    else if (pathOnly === '/' || pathOnly === '' || pathOnly.startsWith('/t/')) next = 'explore';
+    else if (pathOnly.startsWith('/info')) next = 'info';
+    else return; // /shorts, /watch, /search... : ne touche a rien
+    if (this.collapsed) return; // en mode reduit les sections restent a plat (icones)
+    if (this.openSection() !== next) {
+      this.openSection.set(next);
+      try {
+        if (persist && next) localStorage.setItem(SidebarComponent.OPEN_SECTION_KEY, next);
+      } catch {}
+    }
+  }
+
+  // --- Plus/Moins pour les longues listes ---
+  showAllGroups = signal<boolean>(false);
+  displayedGroups = computed(() => {
+    const groups = this.subscriptionGroups();
+    return this.showAllGroups() ? groups : groups.slice(0, SidebarComponent.GROUP_LIMIT);
+  });
+  toggleGroups() { this.showAllGroups.update(v => !v); }
+
+  showAllInstances = signal<boolean>(false);
+  displayedInstances = computed(() => {
+    const list = this.peerTubeInstances();
+    return this.showAllInstances() ? list : list.slice(0, SidebarComponent.INSTANCE_LIMIT);
+  });
+  toggleInstances() { this.showAllInstances.update(v => !v); }
+
   selectPeerTubeInstance(inst: string) {
     if (!inst) return;
     this.instances.setActivePeerTubeInstance(inst);
diff --git a/src/services/i18n.service.ts b/src/services/i18n.service.ts
index 8e685c6..2ed48d2 100644
--- a/src/services/i18n.service.ts
+++ b/src/services/i18n.service.ts
@@ -54,6 +54,9 @@ const EN: Record<string, string> = {
   'nav.liked': 'Liked videos',
   'nav.downloads': 'Downloads',
   'nav.explore': 'Explore',
+  'nav.providers': 'Providers',
+  'nav.info': 'Information',
+  'nav.usage': 'Usage',
   'explore.music': 'Music',
   'explore.gaming': 'Gaming',
   'explore.news': 'News',
@@ -193,6 +196,9 @@ const FR: Record<string, string> = {
   'nav.liked': 'Vidéos que vous aimez',
   'nav.downloads': 'Téléchargements',
   'nav.explore': 'Explorer',
+  'nav.providers': 'Fournisseurs',
+  'nav.info': 'Informations',
+  'nav.usage': 'Utilisation',
   'explore.music': 'Musique',
   'explore.gaming': 'Jeux vidéo',
   'explore.news': 'Actualités',