diff --git a/frontend/lib/services/api/cards_stream_client.dart b/frontend/lib/services/api/cards_stream_client.dart
new file mode 100644
index 0000000..35cf690
--- /dev/null
+++ b/frontend/lib/services/api/cards_stream_client.dart
@@ -0,0 +1,154 @@
+import 'dart:async';
+import 'dart:convert';
+
+import 'package:flutter/foundation.dart';
+import 'package:p_tits_pas/models/carte_bulle.dart';
+import 'package:p_tits_pas/services/api/api_config.dart';
+import 'package:p_tits_pas/services/api/tokenService.dart';
+
+import 'cards_stream_connector_stub.dart'
+    if (dart.library.html) 'cards_stream_connector_web.dart'
+    if (dart.library.io) 'cards_stream_connector_io.dart';
+
+/// Événement temps réel file d'attention — ticket #195.
+class CardsStreamEvent {
+  final String type;
+  final String? cardId;
+  final CarteBulle? card;
+
+  const CardsStreamEvent({
+    required this.type,
+    this.cardId,
+    this.card,
+  });
+}
+
+/// Client SSE `GET /cards/stream` avec reconnexion.
+class CardsStreamClient {
+  final void Function(CardsStreamEvent event) onEvent;
+  final VoidCallback? onReconnectSync;
+
+  CardsStreamClient({
+    required this.onEvent,
+    this.onReconnectSync,
+  });
+
+  final CardsStreamConnector _connector = CardsStreamConnector();
+  bool _started = false;
+  bool _stopRequested = false;
+  int _attempt = 0;
+  Timer? _retryTimer;
+  bool _hadConnection = false;
+
+  void start() {
+    if (_started) return;
+    _started = true;
+    _stopRequested = false;
+    _attempt = 0;
+    unawaited(_connect());
+  }
+
+  void stop() {
+    _stopRequested = true;
+    _started = false;
+    _retryTimer?.cancel();
+    _retryTimer = null;
+    _connector.close();
+  }
+
+  Future<void> _connect() async {
+    if (_stopRequested) return;
+
+    final token = await TokenService.getToken();
+    if (token == null || token.isEmpty) {
+      _scheduleRetry();
+      return;
+    }
+
+    final base =
+        '${ApiConfig.baseUrl}${ApiConfig.cardsStream}'.replaceAll(
+      RegExp(r'/+$'),
+      '',
+    );
+
+    // Web (EventSource) : token en query. IO : Bearer dans le connecteur.
+    final url = kIsWeb
+        ? Uri.parse(base).replace(
+            queryParameters: {'access_token': token},
+          ).toString()
+        : base;
+
+    await _connector.connect(
+      url: url,
+      bearerToken: kIsWeb ? null : token,
+      onEvent: _handleRaw,
+      onError: (_) {
+        if (_stopRequested) return;
+        _connector.close();
+        _scheduleRetry();
+      },
+    );
+  }
+
+  void _handleRaw(String eventType, String data) {
+    if (_stopRequested) return;
+
+    // Premier événement (souvent heartbeat) = connexion OK.
+    if (!_hadConnection) {
+      _hadConnection = true;
+      _attempt = 0;
+    } else if (eventType == 'heartbeat') {
+      _attempt = 0;
+      return;
+    }
+
+    if (eventType == 'heartbeat') return;
+
+    try {
+      final decoded = jsonDecode(data);
+      if (decoded is! Map) return;
+      final map = Map<String, dynamic>.from(decoded);
+      final type = (map['event']?.toString().isNotEmpty == true)
+          ? map['event'].toString()
+          : eventType;
+      final cardId = map['card_id']?.toString();
+      final payload = map['data'];
+
+      CarteBulle? card;
+      if (type == 'response.added' && payload is Map) {
+        final nested = payload['card'];
+        if (nested is Map) {
+          card = CarteBulle.fromJson(Map<String, dynamic>.from(nested));
+        }
+      } else if ((type == 'card.created' || type == 'card.updated') &&
+          payload is Map) {
+        card = CarteBulle.fromJson(Map<String, dynamic>.from(payload));
+      }
+
+      onEvent(
+        CardsStreamEvent(
+          type: type,
+          cardId: cardId ?? card?.id,
+          card: card,
+        ),
+      );
+    } catch (_) {
+      // Événement mal formé : ignorer.
+    }
+  }
+
+  void _scheduleRetry() {
+    if (_stopRequested) return;
+    _retryTimer?.cancel();
+    final delaySec = (1 << _attempt.clamp(0, 4)).clamp(1, 30);
+    _attempt++;
+    _retryTimer = Timer(Duration(seconds: delaySec), () {
+      if (_stopRequested) return;
+      if (_hadConnection) {
+        // Resync REST après coupure pour ne pas manquer d'événements.
+        onReconnectSync?.call();
+      }
+      unawaited(_connect());
+    });
+  }
+}
diff --git a/frontend/lib/services/api/cards_stream_connector_io.dart b/frontend/lib/services/api/cards_stream_connector_io.dart
new file mode 100644
index 0000000..fca64f6
--- /dev/null
+++ b/frontend/lib/services/api/cards_stream_connector_io.dart
@@ -0,0 +1,114 @@
+import 'dart:async';
+import 'dart:convert';
+
+import 'package:http/http.dart' as http;
+
+/// Connecteur SSE via HTTP stream (IO / mobile) — ticket #195.
+class CardsStreamConnector {
+  http.Client? _client;
+  StreamSubscription<List<int>>? _sub;
+  bool _closed = false;
+
+  Future<void> connect({
+    required String url,
+    String? bearerToken,
+    required void Function(String eventType, String data) onEvent,
+    required void Function(Object error) onError,
+  }) async {
+    close();
+    _closed = false;
+    final client = http.Client();
+    _client = client;
+
+    try {
+      final request = http.Request('GET', Uri.parse(url));
+      request.headers['Accept'] = 'text/event-stream';
+      request.headers['Cache-Control'] = 'no-cache';
+      if (bearerToken != null && bearerToken.isNotEmpty) {
+        request.headers['Authorization'] = 'Bearer $bearerToken';
+      }
+
+      final response = await client.send(request);
+      if (response.statusCode != 200) {
+        onError(
+          StateError('SSE cards HTTP ${response.statusCode}'),
+        );
+        close();
+        return;
+      }
+
+      String? eventType;
+      final dataBuf = StringBuffer();
+      final lineBuf = StringBuffer();
+
+      void flushEvent() {
+        if (dataBuf.isEmpty) {
+          eventType = null;
+          return;
+        }
+        onEvent(eventType ?? 'message', dataBuf.toString());
+        dataBuf.clear();
+        eventType = null;
+      }
+
+      void handleLine(String line) {
+        if (line.isEmpty) {
+          flushEvent();
+          return;
+        }
+        if (line.startsWith(':')) return;
+        if (line.startsWith('event:')) {
+          eventType = line.substring(6).trim();
+          return;
+        }
+        if (line.startsWith('data:')) {
+          final payload = line.length > 5 ? line.substring(5) : '';
+          final trimmed = payload.startsWith(' ')
+              ? payload.substring(1)
+              : payload;
+          if (dataBuf.isNotEmpty) dataBuf.write('\n');
+          dataBuf.write(trimmed);
+        }
+      }
+
+      _sub = response.stream.listen(
+        (chunk) {
+          if (_closed) return;
+          lineBuf.write(utf8.decode(chunk, allowMalformed: true));
+          var content = lineBuf.toString();
+          var idx = content.indexOf('\n');
+          while (idx >= 0) {
+            var line = content.substring(0, idx);
+            if (line.endsWith('\r')) {
+              line = line.substring(0, line.length - 1);
+            }
+            handleLine(line);
+            content = content.substring(idx + 1);
+            idx = content.indexOf('\n');
+          }
+          lineBuf
+            ..clear()
+            ..write(content);
+        },
+        onError: (Object e) {
+          if (!_closed) onError(e);
+        },
+        onDone: () {
+          if (!_closed) onError(StateError('SSE cards fermé'));
+        },
+        cancelOnError: true,
+      );
+    } catch (e) {
+      if (!_closed) onError(e);
+      close();
+    }
+  }
+
+  void close() {
+    _closed = true;
+    _sub?.cancel();
+    _sub = null;
+    _client?.close();
+    _client = null;
+  }
+}
diff --git a/frontend/lib/services/api/cards_stream_connector_stub.dart b/frontend/lib/services/api/cards_stream_connector_stub.dart
new file mode 100644
index 0000000..f50d0f8
--- /dev/null
+++ b/frontend/lib/services/api/cards_stream_connector_stub.dart
@@ -0,0 +1,13 @@
+import 'dart:async';
+
+/// Connecteur SSE — stub (tests / plateformes sans impl).
+class CardsStreamConnector {
+  Future<void> connect({
+    required String url,
+    String? bearerToken,
+    required void Function(String eventType, String data) onEvent,
+    required void Function(Object error) onError,
+  }) async {}
+
+  void close() {}
+}
diff --git a/frontend/lib/services/api/cards_stream_connector_web.dart b/frontend/lib/services/api/cards_stream_connector_web.dart
new file mode 100644
index 0000000..9e5e6b7
--- /dev/null
+++ b/frontend/lib/services/api/cards_stream_connector_web.dart
@@ -0,0 +1,60 @@
+// Connecteur web uniquement (import conditionnel).
+// ignore_for_file: avoid_web_libraries_in_flutter, deprecated_member_use
+
+import 'dart:html' as html;
+
+/// Connecteur SSE navigateur (EventSource) — ticket #195.
+/// Auth via `?access_token=` (EventSource ne permet pas Authorization).
+class CardsStreamConnector {
+  html.EventSource? _source;
+  final Map<String, html.EventListener> _listeners = {};
+
+  Future<void> connect({
+    required String url,
+    String? bearerToken,
+    required void Function(String eventType, String data) onEvent,
+    required void Function(Object error) onError,
+  }) async {
+    close();
+    final source = html.EventSource(url);
+    _source = source;
+
+    const names = [
+      'card.created',
+      'card.updated',
+      'card.deleted',
+      'response.added',
+      'heartbeat',
+    ];
+    for (final name in names) {
+      void listener(html.Event raw) {
+        final msg = raw as html.MessageEvent;
+        final data = msg.data?.toString() ?? '';
+        if (data.isEmpty) return;
+        onEvent(name, data);
+      }
+
+      _listeners[name] = listener;
+      source.addEventListener(name, listener);
+    }
+
+    void onErr(html.Event _) {
+      onError(StateError('SSE cards déconnecté'));
+    }
+
+    _listeners['error'] = onErr;
+    source.addEventListener('error', onErr);
+  }
+
+  void close() {
+    final source = _source;
+    if (source != null) {
+      _listeners.forEach((name, listener) {
+        source.removeEventListener(name, listener);
+      });
+      source.close();
+    }
+    _listeners.clear();
+    _source = null;
+  }
+}
diff --git a/frontend/lib/widgets/quotidien/cartes_feed.dart b/frontend/lib/widgets/quotidien/cartes_feed.dart
index a4e0cea..279b021 100644
--- a/frontend/lib/widgets/quotidien/cartes_feed.dart
+++ b/frontend/lib/widgets/quotidien/cartes_feed.dart
@@ -3,6 +3,7 @@ import 'package:google_fonts/google_fonts.dart';
 import 'package:p_tits_pas/models/card_assets.dart';
 import 'package:p_tits_pas/models/carte_bulle.dart';
 import 'package:p_tits_pas/services/api/cards_service.dart';
+import 'package:p_tits_pas/services/api/cards_stream_client.dart';
 import 'package:p_tits_pas/widgets/quotidien/carte.dart';
 import 'package:p_tits_pas/widgets/quotidien/quotidien_theme.dart';
 
@@ -35,15 +36,20 @@ class _CartesFeedState extends State<CartesFeed> {
   bool _fadeTop = false;
   bool _fadeBottom = false;
 
+  CardsStreamClient? _stream;
+
   @override
   void initState() {
     super.initState();
     _scrollController.addListener(_syncScrollFades);
     _load();
+    _startStream();
   }
 
   @override
   void dispose() {
+    _stream?.stop();
+    _stream = null;
     _scrollController.removeListener(_syncScrollFades);
     _scrollController.dispose();
     super.dispose();
@@ -57,6 +63,58 @@ class _CartesFeedState extends State<CartesFeed> {
     }
   }
 
+  void _startStream() {
+    _stream?.stop();
+    _stream = CardsStreamClient(
+      onEvent: _onStreamEvent,
+      onReconnectSync: () {
+        if (mounted) _load();
+      },
+    )..start();
+  }
+
+  void _onStreamEvent(CardsStreamEvent event) {
+    if (!mounted) return;
+    if (event.type == 'heartbeat') return;
+
+    if (event.type == 'card.deleted') {
+      final id = event.cardId;
+      if (id == null || id.isEmpty) return;
+      setState(() {
+        _items = _trier([
+          for (final c in _items)
+            if (c.id != id) c,
+        ]);
+      });
+      WidgetsBinding.instance.addPostFrameCallback((_) => _syncScrollFades());
+      return;
+    }
+
+    final card = event.card;
+    if (card == null) return;
+
+    final filter = widget.placementId;
+    final matchesFilter = filter == null ||
+        filter.isEmpty ||
+        card.idPlacement == filter;
+
+    setState(() {
+      if (!matchesFilter) {
+        _items = _trier([
+          for (final c in _items)
+            if (c.id != card.id) c,
+        ]);
+      } else if (_items.any((c) => c.id == card.id)) {
+        _items = _trier([
+          for (final c in _items) if (c.id == card.id) card else c,
+        ]);
+      } else {
+        _items = _trier([..._items, card]);
+      }
+    });
+    WidgetsBinding.instance.addPostFrameCallback((_) => _syncScrollFades());
+  }
+
   void _syncScrollFades() {
     if (!_scrollController.hasClients) return;
     final position = _scrollController.position;
@@ -189,41 +247,8 @@ class _CartesFeedState extends State<CartesFeed> {
     }
   }
 
-  Future<void> _onAck(CarteBulle card) async {
-    final ok = await showDialog<bool>(
-      context: context,
-      builder: (ctx) => AlertDialog(
-        title: Text(
-          'Prise en compte',
-          style: GoogleFonts.merienda(fontWeight: FontWeight.w600),
-        ),
-        content: Text(
-          card.isArretMaladie
-              ? 'Confirmez-vous avoir pris connaissance de cet arrêt maladie '
-                  '${_periodeDuAu(card)} ?'
-              : card.typeCode.startsWith('absence_enfant')
-                  ? 'Confirmez-vous avoir pris connaissance de l’absence '
-                      '${_periodeDuAu(card)} ?'
-                  : 'Confirmez-vous avoir bien reçu « ${card.titreAffiche} » '
-                      '(${_periodeCourte(card)}) ?',
-          style: GoogleFonts.merriweather(fontSize: 14, height: 1.4),
-        ),
-        actions: [
-          TextButton(
-            onPressed: () => Navigator.pop(ctx, false),
-            child: const Text('Annuler'),
-          ),
-          FilledButton(
-            onPressed: () => Navigator.pop(ctx, true),
-            child: const Text('Bien reçu'),
-          ),
-        ],
-      ),
-    );
-    if (ok == true) {
-      await _respond(card, action: 'ack');
-    }
-  }
+  /// Ack immédiat (arrêt maladie, etc.) — pas de modale : un clic = bien reçu.
+  Future<void> _onAck(CarteBulle card) => _respond(card, action: 'ack');
 
   Future<void> _onRefuse(CarteBulle card) async {
     final comment = await showDialog<String>(
@@ -555,6 +580,24 @@ class _BulleTile extends StatelessWidget {
     return card.statut == CarteStatut.traitee;
   }
 
+  /// Congés (Validée / Refusée) ou carte ack (Bien reçu).
+  bool get _montreStatutReponse {
+    if (card.peutRepondre) return false;
+    if (card.isCongeAm &&
+        (card.statut == CarteStatut.traitee ||
+            card.statut == CarteStatut.refusee)) {
+      return true;
+    }
+    return card.responseMode == CarteResponseMode.ack &&
+        card.statut == CarteStatut.traitee;
+  }
+
+  String get _libelleStatutReponse {
+    if (card.responseMode == CarteResponseMode.ack) return 'Bien reçu';
+    // Accordé à « Demande de congés ».
+    return card.statut == CarteStatut.refusee ? 'Refusée' : 'Validée';
+  }
+
   @override
   Widget build(BuildContext context) {
     final periode = _fmtPeriodeUneLigne();
@@ -632,12 +675,15 @@ class _BulleTile extends StatelessWidget {
                             color: encre.ink,
                           ),
                         ),
-                      ] else if (card.isCongeAm &&
-                          card.statut == CarteStatut.ouverte &&
-                          card.isCreator) ...[
+                      ] else if (card.statut == CarteStatut.ouverte &&
+                          card.isCreator &&
+                          (card.isCongeAm ||
+                              card.responseMode == CarteResponseMode.ack)) ...[
                         const SizedBox(height: 8),
                         Text(
-                          'En attente de réponse',
+                          card.responseMode == CarteResponseMode.ack
+                              ? 'En attente d’acquittement'
+                              : 'En attente de réponse',
                           style: GoogleFonts.merriweather(
                             fontSize: 12,
                             color: QuotidienTheme.muted,
@@ -695,15 +741,10 @@ class _BulleTile extends StatelessWidget {
                                 ),
                               ],
                             )
-                else if (card.isCongeAm &&
-                    (card.statut == CarteStatut.traitee ||
-                        card.statut == CarteStatut.refusee))
+                else if (_montreStatutReponse)
                   Expanded(
                     child: Text(
-                      // Accordé à « Demande de congés ».
-                      card.statut == CarteStatut.refusee
-                          ? 'Refusée'
-                          : 'Validée',
+                      _libelleStatutReponse,
                       textAlign: TextAlign.center,
                       style: GoogleFonts.merienda(
                         fontSize: 14,
@@ -714,10 +755,7 @@ class _BulleTile extends StatelessWidget {
                     ),
                   ),
                 if (card.peutRepondre) const SizedBox(width: 8),
-                if (!(card.isCongeAm &&
-                    (card.statut == CarteStatut.traitee ||
-                        card.statut == CarteStatut.refusee)))
-                  const Spacer(),
+                if (!_montreStatutReponse) const Spacer(),
                 InkWell(
                   onTap: () {
                     ScaffoldMessenger.of(context).showSnackBar(