diff --git a/lmsege/lms/admin.py b/lmsege/lms/admin.py
index a12fa88..a325913 100644
--- a/lmsege/lms/admin.py
+++ b/lmsege/lms/admin.py
@@ -18,9 +18,9 @@ class QuestionInline(StackedInline):
 
 @admin.register(Assignment)
 class AssignmentAdmin(ModelAdmin):
-    list_display = ('title', 'subject', 'is_published', 'is_closed', 'deadline', 'created_at')
+    list_display = ('title', 'subject', 'is_published', 'time_limit', 'deadline', 'created_at')
     list_display_links = ('title',)
-    list_filter = ('subject', 'is_published', 'is_closed')
+    list_filter = ('subject', 'is_published')
     search_fields = ('title', 'description')
     exclude = ('created_by',)
     filter_horizontal = ('assigned_students',)
@@ -102,8 +102,8 @@ class AnswerInline(StackedInline):
 @admin.register(Submission)
 class SubmissionAdmin(ModelAdmin):
     change_list_template = "admin/lms/submission/change_list.html"
-    list_display = ('assignment', 'student', 'status', 'grade', 'submitted_at')
-    list_filter = ('status', 'assignment__subject', 'student')
+    list_display = ('assignment', 'student', 'status', 'is_time_expired', 'grade', 'submitted_at')
+    list_filter = ('status', 'assignment__subject', 'student', 'is_time_expired')
     search_fields = ('student__username', 'assignment__title')
     inlines = [AnswerInline]
 
diff --git a/lmsege/lms/models.py b/lmsege/lms/models.py
index f7593b3..701a17d 100644
--- a/lmsege/lms/models.py
+++ b/lmsege/lms/models.py
@@ -23,7 +23,7 @@ class Assignment(models.Model):
     created_by = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, limit_choices_to={'role__in': ['TEACHER', 'ADMIN']}, verbose_name='Кем создано')
     created_at = models.DateTimeField('Дата создания', auto_now_add=True)
     deadline = models.DateTimeField('Дедлайн', blank=True, null=True, help_text='После этого времени ответы не принимаются.')
-    is_closed = models.BooleanField('Прием ответов закрыт', default=False, help_text='Включите, чтобы вручную закрыть прием ответов на задание.')
+    time_limit = models.PositiveIntegerField('Лимит времени (минуты)', blank=True, null=True, help_text='Например, 235 для 3ч 55м. Оставьте пустым, если без таймера.')
     
     class Meta:
         verbose_name = 'Задание'
@@ -56,6 +56,7 @@ class Question(models.Model):
 
 class Submission(models.Model):
     STATUS_CHOICES = (
+        ('IN_PROGRESS', 'В процессе выполнения'),
         ('PENDING', 'Ожидает проверки'),
         ('GRADED', 'Проверено'),
     )
@@ -64,7 +65,9 @@ class Submission(models.Model):
     grade = models.CharField('Оценка', max_length=10, blank=True, null=True)
     teacher_feedback = models.TextField('Комментарий учителя', blank=True, null=True)
     status = models.CharField('Статус', max_length=20, choices=STATUS_CHOICES, default='PENDING')
+    started_at = models.DateTimeField('Время начала', blank=True, null=True)
     submitted_at = models.DateTimeField('Дата отправки', auto_now_add=True)
+    is_time_expired = models.BooleanField('Время вышло', default=False)
 
     class Meta:
         verbose_name = 'Ответ ученика'
diff --git a/lmsege/lms/templates/lms/assignment_detail.html b/lmsege/lms/templates/lms/assignment_detail.html
index be7c4e9..dfa091b 100644
--- a/lmsege/lms/templates/lms/assignment_detail.html
+++ b/lmsege/lms/templates/lms/assignment_detail.html
@@ -94,13 +94,87 @@
             </div>
             {% endfor %}
         </div>
+    {% elif needs_start %}
+        <div class="mb-6 p-8 text-center rounded-2xl border bg-indigo-50 border-indigo-200">
+            <span class="material-icons text-indigo-500 text-6xl mb-4">hourglass_top</span>
+            <h4 class="text-2xl font-bold mb-2 text-indigo-900">Задание на время</h4>
+            <p class="text-indigo-800 text-lg mb-6">На выполнение этого задания отводится <strong>{{ assignment.time_limit }} минут(ы)</strong>. Как только вы нажмете кнопку ниже, запустится обратный отсчет. По истечении времени ваши ответы будут отправлены автоматически.</p>
+            
+            <form method="post">
+                {% csrf_token %}
+                <input type="hidden" name="action" value="start">
+                <button type="submit" class="px-8 py-4 bg-indigo-600 text-white text-lg font-bold rounded-xl shadow hover:bg-indigo-700 transition">
+                    Начать выполнение
+                </button>
+            </form>
+        </div>
     {% elif not can_submit %}
         <div class="mb-6 p-4 rounded-lg border bg-red-50 text-red-800 border-red-200">
             <h4 class="font-bold mb-2">Прием ответов завершен</h4>
-            <p>Вы больше не можете отправлять ответы, так как дедлайн истек или преподаватель закрыл задание.</p>
+            <p>Вы больше не можете отправлять ответы, так как дедлайн истек или время на выполнение закончилось.</p>
         </div>
     {% else %}
-        <form method="post" enctype="multipart/form-data" class="space-y-6">
+        {% if time_left_seconds is not None %}
+        <div id="timer-banner" class="sticky top-4 z-50 mb-6 p-4 rounded-xl border bg-indigo-600 text-white shadow-lg flex justify-between items-center">
+            <div class="flex items-center gap-2">
+                <span class="material-icons animate-pulse">timer</span>
+                <span class="font-medium text-lg">Осталось времени:</span>
+            </div>
+            <div class="text-2xl font-mono font-bold tracking-wider" id="countdown-display">
+                --:--:--
+            </div>
+        </div>
+        <script>
+            let timeLeft = {{ time_left_seconds }};
+            const display = document.getElementById('countdown-display');
+            const form = document.getElementById('assignment-form');
+            
+            function updateTimer() {
+                if (timeLeft <= 0) {
+                    display.textContent = '00:00:00';
+                    display.classList.add('text-red-300');
+                    // Auto submit
+                    if (form) {
+                        // Prevent multiple submissions
+                        form.onsubmit = null;
+                        const btn = form.querySelector('button[type="submit"]');
+                        if (btn) btn.disabled = true;
+                        
+                        // Append a hidden flag
+                        const input = document.createElement('input');
+                        input.type = 'hidden';
+                        input.name = 'auto_submit';
+                        input.value = '1';
+                        form.appendChild(input);
+                        
+                        form.submit();
+                    }
+                    return;
+                }
+                
+                const h = Math.floor(timeLeft / 3600);
+                const m = Math.floor((timeLeft % 3600) / 60);
+                const s = timeLeft % 60;
+                display.textContent = 
+                    (h > 0 ? (h < 10 ? '0' + h : h) + ':' : '') + 
+                    (m < 10 ? '0' + m : m) + ':' + 
+                    (s < 10 ? '0' + s : s);
+                    
+                if (timeLeft < 60) {
+                    display.classList.add('text-red-300', 'animate-pulse');
+                }
+                
+                timeLeft--;
+                setTimeout(updateTimer, 1000);
+            }
+            
+            if (timeLeft > 0) {
+                updateTimer();
+            }
+        </script>
+        {% endif %}
+        
+        <form id="assignment-form" method="post" enctype="multipart/form-data" class="space-y-6">
             {% csrf_token %}
             
             {% for q, field_type, field in question_fields %}
diff --git a/lmsege/lms/templates/lms/dashboard.html b/lmsege/lms/templates/lms/dashboard.html
index d698a83..b5857ce 100644
--- a/lmsege/lms/templates/lms/dashboard.html
+++ b/lmsege/lms/templates/lms/dashboard.html
@@ -52,15 +52,15 @@
                         Добавлено: {{ assignment.created_at|date:"d M Y" }}
                     </span>
                     {% if assignment.deadline %}
-                    <span class="flex items-center gap-1 {% if assignment.is_closed or assignment.deadline < now %}text-red-500{% else %}text-gray-500{% endif %}">
+                    <span class="flex items-center gap-1 {% if assignment.deadline < now %}text-red-500{% else %}text-gray-500{% endif %}">
                         <span class="material-icons text-[14px]">timer</span> 
                         Дедлайн: {{ assignment.deadline|date:"d M Y, H:i" }}
                     </span>
                     {% endif %}
-                    {% if assignment.is_closed %}
-                    <span class="flex items-center gap-1 text-red-500 font-medium mt-1">
-                        <span class="material-icons text-[14px]">lock</span> 
-                        Прием ответов закрыт
+                    {% if assignment.time_limit %}
+                    <span class="flex items-center gap-1 text-indigo-600 font-medium mt-1">
+                        <span class="material-icons text-[14px]">hourglass_empty</span> 
+                        Время на решение: {{ assignment.time_limit }} мин.
                     </span>
                     {% endif %}
                 </div>
diff --git a/lmsege/lms/views.py b/lmsege/lms/views.py
index bae142b..db48349 100644
--- a/lmsege/lms/views.py
+++ b/lmsege/lms/views.py
@@ -62,31 +62,64 @@ def assignment_detail(request, pk):
     submission = Submission.objects.filter(assignment=assignment, student=request.user).first()
     
     from django.utils import timezone
+    import datetime
+    
+    now = timezone.now()
     can_submit = True
-    if assignment.is_closed:
-        can_submit = False
-    if assignment.deadline and timezone.now() > assignment.deadline:
+    time_left_seconds = None
+    needs_start = False
+
+    if assignment.deadline and now > assignment.deadline:
         can_submit = False
 
-    if submission:
-        if request.method == 'POST':
-            # Do not allow updating
+    if assignment.time_limit:
+        if not submission:
+            needs_start = True
+            can_submit = False # Can't submit until started
+        elif submission.status == 'IN_PROGRESS':
+            if submission.started_at:
+                elapsed = (now - submission.started_at).total_seconds()
+                allowed = assignment.time_limit * 60
+                if elapsed > allowed + 60: # 1 minute grace period for network latency
+                    can_submit = False
+                    submission.is_time_expired = True
+                    submission.status = 'PENDING' # Or graded with 0
+                    submission.save()
+                else:
+                    time_left_seconds = int(allowed - elapsed)
+                    if time_left_seconds < 0:
+                        time_left_seconds = 0
+        else:
+            can_submit = False # Already submitted
+
+    if request.method == 'POST':
+        if needs_start and 'action' in request.POST and request.POST['action'] == 'start':
+            Submission.objects.create(
+                assignment=assignment, 
+                student=request.user, 
+                status='IN_PROGRESS', 
+                started_at=now
+            )
+            return redirect('lms:assignment_detail', pk=pk)
+
+        if submission and submission.status != 'IN_PROGRESS':
             return redirect('lms:dashboard')
-        form = None
-    else:
-        if not can_submit:
-            form = None
-        elif request.method == 'POST':
+            
+        if can_submit and not needs_start:
             form = AnswersForm(request.POST, request.FILES, questions=questions)
             if form.is_valid():
-                submission = Submission.objects.create(assignment=assignment, student=request.user)
+                if not submission:
+                    submission = Submission.objects.create(assignment=assignment, student=request.user)
                 
                 all_auto = True
                 total_points = 0
                 max_points = 0
                 
                 for q in questions:
-                    answer_obj = Answer(submission=submission, question=q)
+                    answer_obj = Answer.objects.filter(submission=submission, question=q).first()
+                    if not answer_obj:
+                        answer_obj = Answer(submission=submission, question=q)
+                        
                     if q.question_type == 'TEXT_AUTO':
                         val = form.cleaned_data.get(f'answer_{q.id}', '')
                         answer_obj.text_answer = val
@@ -142,7 +175,12 @@ def assignment_detail(request, pk):
                 submission.save()
                 return redirect('lms:dashboard')
         else:
+            form = None
+    else:
+        if can_submit and not needs_start:
             form = AnswersForm(questions=questions)
+        else:
+            form = None
         
     question_fields = []
     if form:
@@ -165,4 +203,6 @@ def assignment_detail(request, pk):
         'questions': questions,
         'question_fields': question_fields,
         'can_submit': can_submit,
+        'needs_start': needs_start,
+        'time_left_seconds': time_left_seconds,
     })