diff --git a/frontend/src/components/Sidebar.jsx b/frontend/src/components/Sidebar.jsx
index 454991f..189eacc 100644
--- a/frontend/src/components/Sidebar.jsx
+++ b/frontend/src/components/Sidebar.jsx
@@ -57,12 +57,20 @@ export default function Sidebar({ sessions, currentSession, onNewChat, onLoadSes
             {sessions.length === 0 ? "No chats yet. Start one!" : "No results."}
           </p>
         )}
-        {filtered.map(s => (
-          <div key={s.id} className={`group flex items-center gap-1 rounded-lg mb-0.5 transition
-            ${currentSession === s.id ? "bg-gray-700" : "hover:bg-gray-800"}`}>
+        {filtered.map(s => {
+          const isActive = currentSession === s.id;
+          return (
+          <div key={s.id} className={`relative group flex items-center rounded-lg mb-0.5 transition
+            ${isActive ? "bg-gray-700" : "hover:bg-gray-800"}`}>
+            {/* Activity indicator: always rendered, transparent when inactive */}
+            <span
+              aria-hidden="true"
+              className={`absolute left-2.5 top-1/2 -translate-y-1/2 w-1.5 h-1.5 rounded-full bg-purple-400 transition-opacity duration-300
+                ${isActive ? "opacity-100 animate-pulse" : "opacity-0"}`}
+            />
             <button onClick={()=>onLoadSession(s.id)}
-              className="flex-1 text-left text-xs px-3 py-2 truncate text-gray-400 group-hover:text-gray-200">
-              <span className={currentSession === s.id ? "text-white" : ""}>
+              className="flex-1 text-left text-xs pl-6 pr-3 py-2 truncate text-gray-400 group-hover:text-gray-200">
+              <span className={isActive ? "text-white" : ""}>
                 <span className="inline-flex items-center gap-1.5">
                   <ChatIcon className="w-3.5 h-3.5 text-gray-500" />
                   <span>{s.title || "New Chat"}</span>
@@ -77,7 +85,8 @@ export default function Sidebar({ sessions, currentSession, onNewChat, onLoadSes
               ×
             </button>
           </div>
-        ))}
+          );
+        })}
       </div>
 
       {/* Footer */}