diff --git a/polls/migrations/0011_remove_vote_question.py b/polls/migrations/0011_remove_vote_question.py
new file mode 100644
index 0000000..ab6c9e9
--- /dev/null
+++ b/polls/migrations/0011_remove_vote_question.py
@@ -0,0 +1,17 @@
+# Generated by Django 4.2.4 on 2023-09-14 12:47
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('polls', '0010_sentimentvote'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='vote',
+            name='question',
+        ),
+    ]
diff --git a/polls/migrations/0012_vote_question.py b/polls/migrations/0012_vote_question.py
new file mode 100644
index 0000000..4b4c620
--- /dev/null
+++ b/polls/migrations/0012_vote_question.py
@@ -0,0 +1,19 @@
+# Generated by Django 4.2.4 on 2023-09-14 13:15
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('polls', '0011_remove_vote_question'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='vote',
+            name='question',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, to='polls.question'),
+        ),
+    ]
diff --git a/polls/migrations/0013_alter_vote_question.py b/polls/migrations/0013_alter_vote_question.py
new file mode 100644
index 0000000..9bb9277
--- /dev/null
+++ b/polls/migrations/0013_alter_vote_question.py
@@ -0,0 +1,19 @@
+# Generated by Django 4.2.4 on 2023-09-14 13:15
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('polls', '0012_vote_question'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='vote',
+            name='question',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='polls.question'),
+        ),
+    ]
diff --git a/polls/models.py b/polls/models.py
index a9c0508..10be79f 100644
--- a/polls/models.py
+++ b/polls/models.py
@@ -172,8 +172,8 @@ class Question(models.Model):
                 vote.update(vote_types=True)
                 self.save()
             else:
-                return 'already_upvoted'
-        return 'ok'
+                return False
+        return True
 
 
     def downvote(self, user):
@@ -187,8 +187,8 @@ class Question(models.Model):
                 vote.update(vote_types=False)
                 self.save()
             else:
-                return 'already_downvoted'
-        return 'ok'
+                return False
+        return True
 
 
 class Choice(models.Model):
diff --git a/polls/templates/polls/base.html b/polls/templates/polls/base.html
index fc6124b..fa30709 100644
--- a/polls/templates/polls/base.html
+++ b/polls/templates/polls/base.html
@@ -6,10 +6,6 @@
 		<meta charset="UTF-8" />
 		<meta name="viewport" content="width=device-width, initial-scale=1.0" />
 		<script src="https://cdn.tailwindcss.com"></script>
-		<script
-			src="https://unpkg.com/htmx.org@1.9.5"
-			integrity="sha384-xcuj3WpfgjlKF+FXhSQFQ0ZNr39ln+hwjN3npfM9VBnUskLolQAcN80McRIVOPuO"
-			crossorigin="anonymous"></script>
 		<script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
 		<script src="{% static 'polls/js/detail.js' %}"></script>
 		<script src="{% static 'polls/base.css' %}"></script>
diff --git a/polls/templates/polls/index.html b/polls/templates/polls/index.html
index d870900..fb8fdb2 100644
--- a/polls/templates/polls/index.html
+++ b/polls/templates/polls/index.html
@@ -3,8 +3,13 @@
   <!-- Navbar -->
   <nav class="bg-blue-500 p-4 shadow-xl border-b-2 border-solid border-neutral-700">
     <div class="container mx-auto flex items-center justify-between">
-      <div class="text-2xl font-bold text-white">📝KU POLL</div>
-
+      <div class="text-2xl font-bold text-white">
+        {% if user.is_authenticated %}
+        📝KU POLL | 👋 Hi! {{ user.username }}
+        {% else %}
+        📝KU POLL
+        {% endif %}
+      </div>
       <!-- Button -->
       <div>
         {% comment %}
diff --git a/polls/templates/registration/login.html b/polls/templates/registration/login.html
index 99361b9..398cecb 100644
--- a/polls/templates/registration/login.html
+++ b/polls/templates/registration/login.html
@@ -7,7 +7,7 @@
     <script src="https://cdn.tailwindcss.com"></script>
   </head>
   <body class="bg-gray-100 min-h-screen flex items-center justify-center">
-    <div class="bg-white p-8 shadow-md rounded-md w-96">
+    <div class="bg-white p-8 shadow-md rounded-md w-96 border-solid border-neutral-500 border-2">
       <h2 class="text-3xl font-semibold text-center mb-6">Sign In</h2>
       <form method="post">
         {% csrf_token %}
diff --git a/polls/templates/registration/signup.html b/polls/templates/registration/signup.html
index 0bac13d..6f9ba91 100644
--- a/polls/templates/registration/signup.html
+++ b/polls/templates/registration/signup.html
@@ -7,7 +7,7 @@
 </head>
 <body class="bg-gray-100">
     <div class="min-h-screen flex items-center justify-center">
-        <div class="bg-white p-8 shadow-md rounded-md w-96">
+        <div class="bg-white p-8 shadow-md rounded-md w-96  border-solid border-neutral-500 border-2">
             <h2 class="text-2xl font-semibold mb-6">Sign Up</h2>
             <form method="post">
                 {% csrf_token %}
diff --git a/polls/tests.py b/polls/tests.py
deleted file mode 100644
index db9a67f..0000000
--- a/polls/tests.py
+++ /dev/null
@@ -1,224 +0,0 @@
-import datetime
-
-from django.test import TestCase
-from django.utils import timezone
-from django.urls import reverse
-from django.contrib.auth.models import User
-
-from .models import Question
-
-
-class QuestionModelTests(TestCase):
-    def test_was_published_recently_with_future_question(self):
-        """
-        was_published_recently() returns False for questions whose pub_date
-        is in the future.
-        """
-        time = timezone.now() + datetime.timedelta(days=30)
-        future_question = Question(pub_date=time)
-        self.assertIs(future_question.was_published_recently(), False)
-
-    def test_was_published_recently_with_old_question(self):
-        """
-        was_published_recently() returns False for questions whose pub_date
-        is older than 1 day.
-        """
-        time = timezone.now() - datetime.timedelta(days=1, seconds=1)
-        old_question = Question(pub_date=time)
-        self.assertIs(old_question.was_published_recently(), False)
-
-    def test_was_published_recently_with_recent_question(self):
-        """
-        was_published_recently() returns True for questions whose pub_date
-        is within the last day.
-        """
-        time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
-        recent_question = Question(pub_date=time)
-        self.assertIs(recent_question.was_published_recently(), True)
-
-    def test_is_published_with_future_question(self):
-        """
-        is_published() should return False for questions whos pub_date is in the
-        future.
-        """
-        future_date = timezone.now() + datetime.timedelta(days=30)
-        future_question = Question(pub_date=future_date)
-        self.assertIs(future_question.is_published(), False)
-
-    def test_default_pub_date(self):
-        """
-        Questions with the default pub_date (now) are displayed on the index page.
-        """
-        question = Question.objects.create(question_text="Default pub date question.")
-
-        response = self.client.get(reverse("polls:index"))
-        self.assertQuerySetEqual(
-            response.context["latest_question_list"],
-            [question],
-        )
-
-    def test_is_published_with_past_question(self):
-        """
-        is_published() should return True for questions whose pub_date is in the
-        past.
-        """
-        past_date = timezone.now() - datetime.timedelta(days=1)
-        past_question = Question(pub_date=past_date)
-        self.assertIs(past_question.is_published(), True)
-
-    def test_can_vote_with_question_not_ended(self):
-        """
-        can_vote() should return True for questions that are published and have not
-        ended.
-        """
-        pub_date = timezone.now() - datetime.timedelta(hours=1)
-        end_date = timezone.now() + datetime.timedelta(hours=1)
-        question = Question(pub_date=pub_date, end_date=end_date)
-        self.assertIs(question.can_vote(), True)
-
-    def test_can_vote_with_question_ended(self):
-        """
-        can_vote() should return False for questions that are published but have
-        ended.
-        """
-        pub_date = timezone.now() - datetime.timedelta(hours=2)
-        end_date = timezone.now() - datetime.timedelta(hours=1)
-        question = Question(pub_date=pub_date, end_date=end_date)
-        self.assertIs(question.can_vote(), False)
-
-    def test_can_vote_with_question_no_end_date(self):
-        """
-        can_vote() should return True for questions that are published and have no
-        specified end date.
-        """
-        pub_date = timezone.now() - datetime.timedelta(hours=1)
-        question = Question(pub_date=pub_date, end_date=None)
-        self.assertIs(question.can_vote(), True)
-
-    def test_can_vote_with_question_ending_in_future(self):
-        """
-        can_vote() should return True for questions that are published and
-        the current time is within the allowed voting period.
-        """
-        pub_date = timezone.now() - datetime.timedelta(hours=1)
-        end_date = timezone.now() + datetime.timedelta(hours=2)
-        question = Question(pub_date=pub_date, end_date=end_date)
-        self.assertIs(question.can_vote(), True)
-
-
-def create_question(self, question_text, days, pub_date=None):
-    """
-    Create a question with the given `question_text` and published the
-    given number of `days` offset to now (negative for questions published
-    in the past, positive for questions that have yet to be published).
-    """
-    time = timezone.now() + timezone.timedelta(days=days)
-    if pub_date is not None:
-        time = pub_date
-    return Question.objects.create(question_text=question_text, pub_date=time)
-
-
-class QuestionIndexViewTests(TestCase):
-    def test_no_questions(self):
-        """
-        If no questions exist, an appropriate message is displayed.
-        """
-        response = self.client.get(reverse("polls:index"))
-        self.assertEqual(response.status_code, 200)
-        self.assertQuerySetEqual(response.context["latest_question_list"], [])
-
-    def test_past_question(self):
-        """
-        Questions with a pub_date in the past are displayed on the
-        index page.
-        """
-        question = Question.objects.create(question_text="Past question.")
-        question.pub_date = timezone.now() - timezone.timedelta(days=30)
-        question.save()
-        response = self.client.get(reverse("polls:index"))
-        self.assertQuerySetEqual(
-            response.context["latest_question_list"],
-            [question],
-        )
-
-    def test_future_question(self):
-        """
-        Questions with a pub_date in the future aren't displayed on
-        the index page.
-        """
-        future_question = Question.objects.create(question_text="Future question.")
-        future_question.pub_date = timezone.now() + timezone.timedelta(days=30)
-        future_question.save()
-        response = self.client.get(reverse("polls:index"))
-        self.assertQuerySetEqual(response.context["latest_question_list"], [])
-
-    def test_future_question_and_past_question(self):
-        """
-        Even if both past and future questions exist, only past questions
-        are displayed.
-        """
-        past_question = Question.objects.create(question_text="Past question.")
-        past_question.pub_date = timezone.now() - timezone.timedelta(days=30)
-        past_question.save()
-
-        future_question = Question.objects.create(question_text="Future question.")
-        future_question.pub_date = timezone.now() + timezone.timedelta(days=30)
-        future_question.save()
-
-        response = self.client.get(reverse("polls:index"))
-        self.assertQuerySetEqual(
-            response.context["latest_question_list"],
-            [past_question],
-        )
-
-    def test_two_past_questions(self):
-        """
-        The questions index page may display multiple questions.
-        """
-        question1 = Question.objects.create(question_text="Past question 1.")
-        question1.pub_date = timezone.now() - timezone.timedelta(days=30)
-        question1.save()
-
-        question2 = Question.objects.create(question_text="Past question 2.")
-        question2.pub_date = timezone.now() - timezone.timedelta(days=5)
-        question2.save()
-
-        response = self.client.get(reverse("polls:index"))
-        self.assertQuerySetEqual(
-            response.context["latest_question_list"],
-            [question2, question1],
-        )
-
-
-class QuestionDetailViewTests(TestCase):
-    def test_future_question(self):
-        """
-        The detail view of a question with a pub_date in the future
-        returns a 404 not found.
-        """
-        future_question = Question.objects.create(question_text="Future question.")
-        future_question.pub_date = timezone.now() + timezone.timedelta(days=5)
-        future_question.save()
-
-        user = User.objects.create_user(username="testcase", password="123test123")
-        self.client.login(username="testcase", password="123test123")
-
-        url = reverse("polls:detail", args=(future_question.id,))
-        response = self.client.get(url)
-        self.assertEqual(response.status_code, 404)
-
-    def test_past_question(self):
-        """
-        The detail view of a question with a pub_date in the past
-        displays the question's text.
-        """
-        past_question = Question.objects.create(question_text="Past Question.")
-        past_question.pub_date = timezone.now() - timezone.timedelta(days=5)
-        past_question.save()
-
-        user = User.objects.create_user(username="testcase", password="123test123")
-        self.client.login(username="testcase", password="123test123")
-
-        url = reverse("polls:detail", args=(past_question.id,))
-        response = self.client.get(url)
-        self.assertContains(response, past_question.question_text)
diff --git a/polls/tests/__init__.py b/polls/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/polls/tests/base.py b/polls/tests/base.py
new file mode 100644
index 0000000..1e2db85
--- /dev/null
+++ b/polls/tests/base.py
@@ -0,0 +1,14 @@
+from django.utils import timezone
+from django.contrib.auth.models import User
+
+from ..models import Question, Vote, Choice
+
+
+def create_question(question_text, day=0):
+    """
+    Create a question with the given `question_text` and published the
+    given number of `days` offset to now (negative for questions published
+    in the past, positive for questions that have yet to be published).
+    """
+    time = timezone.now() + timezone.timedelta(days=day)
+    return Question.objects.create(question_text=question_text, pub_date=time)
\ No newline at end of file
diff --git a/polls/tests/test_detail_views.py b/polls/tests/test_detail_views.py
new file mode 100644
index 0000000..db2f3bc
--- /dev/null
+++ b/polls/tests/test_detail_views.py
@@ -0,0 +1,43 @@
+from django.test import TestCase, Client
+from django.utils import timezone
+from django.urls import reverse
+from django.contrib.auth.models import User
+
+from .base import create_question
+
+
+class QuestionDetailViewTests(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.user = User.objects.create_user(username="test_user_123", password="aaa123321aaa")
+        cls.client = Client()
+
+    def test_future_question(self):
+        """
+        The detail view of a question with a pub_date in the future
+        returns a 404 not found.
+        """
+        future_question = create_question(question_text="Future question.", day=10)
+        future_question.save()
+
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        url = reverse("polls:detail", args=(future_question.id,))
+        respone = self.client.get(url)
+        self.assertEqual(respone.status_code, 404)
+
+    def test_past_question(self):
+        """
+        The detail view of a question with a pub_date in the past
+        displays the question's text.
+        """
+        past_question = create_question(question_text="Past Question.", day=-10)
+        past_question.save()
+
+        self.client.login(username=self.user.username, password='aaa123321aaa')
+
+        url = reverse("polls:detail", args=(past_question.id,))
+        response = self.client.get(url)
+        self.assertEqual(response.status_code, 200)
+
+        self.assertContains(response, past_question.question_text)
diff --git a/polls/tests/test_index_views.py b/polls/tests/test_index_views.py
new file mode 100644
index 0000000..4cf0ad2
--- /dev/null
+++ b/polls/tests/test_index_views.py
@@ -0,0 +1,77 @@
+from django.test import TestCase
+from django.utils import timezone
+from django.urls import reverse
+
+from ..models import Question
+
+
+class QuestionIndexViewTests(TestCase):
+    def test_no_questions(self):
+        """
+        If no questions exist, an appropriate message is displayed.
+        """
+        response = self.client.get(reverse("polls:index"))
+        self.assertEqual(response.status_code, 200)
+        self.assertQuerySetEqual(response.context["latest_question_list"], [])
+
+    def test_past_question(self):
+        """
+        Questions with a pub_date in the past are displayed on the
+        index page.
+        """
+        question = Question.objects.create(question_text="Past question.")
+        question.pub_date = timezone.now() - timezone.timedelta(days=30)
+        question.save()
+        response = self.client.get(reverse("polls:index"))
+        self.assertQuerySetEqual(
+            response.context["latest_question_list"],
+            [question],
+        )
+
+    def test_future_question(self):
+        """
+        Questions with a pub_date in the future aren't displayed on
+        the index page.
+        """
+        future_question = Question.objects.create(question_text="Future question.")
+        future_question.pub_date = timezone.now() + timezone.timedelta(days=30)
+        future_question.save()
+        response = self.client.get(reverse("polls:index"))
+        self.assertQuerySetEqual(response.context["latest_question_list"], [])
+
+    def test_future_question_and_past_question(self):
+        """
+        Even if both past and future questions exist, only past questions
+        are displayed.
+        """
+        past_question = Question.objects.create(question_text="Past question.")
+        past_question.pub_date = timezone.now() - timezone.timedelta(days=30)
+        past_question.save()
+
+        future_question = Question.objects.create(question_text="Future question.")
+        future_question.pub_date = timezone.now() + timezone.timedelta(days=30)
+        future_question.save()
+
+        response = self.client.get(reverse("polls:index"))
+        self.assertQuerySetEqual(
+            response.context["latest_question_list"],
+            [past_question],
+        )
+
+    def test_two_past_questions(self):
+        """
+        The questions index page may display multiple questions.
+        """
+        question1 = Question.objects.create(question_text="Past question 1.")
+        question1.pub_date = timezone.now() - timezone.timedelta(days=30)
+        question1.save()
+
+        question2 = Question.objects.create(question_text="Past question 2.")
+        question2.pub_date = timezone.now() - timezone.timedelta(days=5)
+        question2.save()
+
+        response = self.client.get(reverse("polls:index"))
+        self.assertQuerySetEqual(
+            response.context["latest_question_list"],
+            [question2, question1],
+        )
diff --git a/polls/tests/test_question_model.py b/polls/tests/test_question_model.py
new file mode 100644
index 0000000..6514de0
--- /dev/null
+++ b/polls/tests/test_question_model.py
@@ -0,0 +1,105 @@
+import datetime
+
+from django.test import TestCase
+from django.utils import timezone
+from django.urls import reverse
+
+from ..models import Question
+
+
+class QuestionModelTests(TestCase):
+    def test_was_published_recently_with_future_question(self):
+        """
+        was_published_recently() returns False for questions whose pub_date
+        is in the future.
+        """
+        time = timezone.now() + datetime.timedelta(days=30)
+        future_question = Question(pub_date=time)
+        self.assertIs(future_question.was_published_recently(), False)
+
+    def test_was_published_recently_with_old_question(self):
+        """
+        was_published_recently() returns False for questions whose pub_date
+        is older than 1 day.
+        """
+        time = timezone.now() - datetime.timedelta(days=1, seconds=1)
+        old_question = Question(pub_date=time)
+        self.assertIs(old_question.was_published_recently(), False)
+
+    def test_was_published_recently_with_recent_question(self):
+        """
+        was_published_recently() returns True for questions whose pub_date
+        is within the last day.
+        """
+        time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
+        recent_question = Question(pub_date=time)
+        self.assertIs(recent_question.was_published_recently(), True)
+
+    def test_is_published_with_future_question(self):
+        """
+        is_published() should return False for questions whos pub_date is in the
+        future.
+        """
+        future_date = timezone.now() + datetime.timedelta(days=30)
+        future_question = Question(pub_date=future_date)
+        self.assertIs(future_question.is_published(), False)
+
+    def test_default_pub_date(self):
+        """
+        Questions with the default pub_date (now) are displayed on the index page.
+        """
+        question = Question.objects.create(question_text="Default pub date question.")
+
+        response = self.client.get(reverse("polls:index"))
+        self.assertQuerySetEqual(
+            response.context["latest_question_list"],
+            [question],
+        )
+
+    def test_is_published_with_past_question(self):
+        """
+        is_published() should return True for questions whose pub_date is in the
+        past.
+        """
+        past_date = timezone.now() - datetime.timedelta(days=1)
+        past_question = Question(pub_date=past_date)
+        self.assertIs(past_question.is_published(), True)
+
+    def test_can_vote_with_question_not_ended(self):
+        """
+        can_vote() should return True for questions that are published and have not
+        ended.
+        """
+        pub_date = timezone.now() - datetime.timedelta(hours=1)
+        end_date = timezone.now() + datetime.timedelta(hours=1)
+        question = Question(pub_date=pub_date, end_date=end_date)
+        self.assertIs(question.can_vote(), True)
+
+    def test_can_vote_with_question_ended(self):
+        """
+        can_vote() should return False for questions that are published but have
+        ended.
+        """
+        pub_date = timezone.now() - datetime.timedelta(hours=2)
+        end_date = timezone.now() - datetime.timedelta(hours=1)
+        question = Question(pub_date=pub_date, end_date=end_date)
+        self.assertIs(question.can_vote(), False)
+
+    def test_can_vote_with_question_no_end_date(self):
+        """
+        can_vote() should return True for questions that are published and have no
+        specified end date.
+        """
+        pub_date = timezone.now() - datetime.timedelta(hours=1)
+        question = Question(pub_date=pub_date, end_date=None)
+        self.assertIs(question.can_vote(), True)
+
+    def test_can_vote_with_question_ending_in_future(self):
+        """
+        can_vote() should return True for questions that are published and
+        the current time is within the allowed voting period.
+        """
+        pub_date = timezone.now() - datetime.timedelta(hours=1)
+        end_date = timezone.now() + datetime.timedelta(hours=2)
+        question = Question(pub_date=pub_date, end_date=end_date)
+        self.assertIs(question.can_vote(), True)
\ No newline at end of file
diff --git a/polls/tests/test_vote_views.py b/polls/tests/test_vote_views.py
new file mode 100644
index 0000000..393650e
--- /dev/null
+++ b/polls/tests/test_vote_views.py
@@ -0,0 +1,86 @@
+from django.test import TestCase, Client
+from django.urls import reverse
+from django.contrib.auth.models import User
+
+from .base import create_question
+from ..models import Vote, Choice
+
+class VoteViewTest(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.question = create_question(question_text="Test Question", day=0)
+        cls.choice1 = Choice.objects.create(question=cls.question, choice_text="Test Choice 1")
+        cls.choice2 = Choice.objects.create(question=cls.question, choice_text="Test Choice 2")
+        cls.user = User.objects.create_user(username="test_user_123", password="aaa123321aaa")
+        cls.client = Client()
+
+    def test_vote_with_valid_choice(self):
+        """
+        Test the vote view with a valid choice selection.
+        """
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        response = self.client.post(reverse("polls:vote", args=(self.question.id,)), 
+                                    {'choice' : self.choice1.id})
+        
+        self.assertRedirects(response, reverse("polls:results", args=(self.question.id,)))
+        self.assertTrue(Vote.objects.filter(user=self.user, question=self.question).exists())
+
+    def test_vote_with_invalid_choice(self):
+        """
+        Test the vote view with an invalid choice selection.
+        """
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        response = self.client.post(reverse("polls:vote", args=(self.question.id,)), 
+                                    {'choice' : 1000})
+        
+        self.assertRedirects(response, reverse('polls:detail', args=(self.question.id,)))
+
+    def test_vote_without_login(self):
+        """
+        Test the vote view when the user is not logged in.
+        """
+        response = self.client.post(reverse("polls:vote", args=(self.question.id,)), 
+                                    {'choice' : self.choice1})
+        
+        self.assertRedirects(response, "/accounts/login/?next=/polls/1/vote/")
+
+    def test_vote_voting_not_allowed(self):
+        """
+        Test the vote view when voting is not allowed for the question.
+        """
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        self.question_2 = create_question(question_text="Test not allow", day=10)
+        self.choice_2 = Choice.objects.create(question=self.question_2, choice_text="Test Choice 2_2")
+
+        response = self.client.post(reverse("polls:vote", args=(self.question_2.id,)),
+                                            {"choice" : self.choice_2.id})
+        
+        self.assertRedirects(response, reverse('polls:index'))
+
+    def test_vote_with_no_post_data(self):
+        """
+        Test the vote view when vote with no post data.
+        """
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        response = self.client.post(reverse("polls:vote", args=(self.question.id,)))
+
+        self.assertRedirects(response, reverse('polls:detail', args=(self.question.id,)))
+
+    def test_update_vote_when_vote_on_new_choice(self):
+        """
+        Test the vote when same user vote on same question but change the choice.
+        """
+        self.client.login(username=self.user.username, password="aaa123321aaa")
+
+        response_1 = self.client.post(reverse("polls:vote", args=(self.question.id,)), {"choice": self.choice1.id})
+        self.assertRedirects(response_1, reverse('polls:results', args=(self.question.id,)))
+
+        response_2 = self.client.post(reverse("polls:vote", args=(self.question.id,)), {"choice": self.choice2.id})
+        self.assertRedirects(response_2, reverse('polls:results', args=(self.question.id,)))
+        
+        self.assertFalse(Vote.objects.filter(user=self.user, question=self.question, choice=self.choice1).exists())
+        self.assertTrue(Vote.objects.filter(user=self.user, question=self.question, choice=self.choice2).exists())
\ No newline at end of file
diff --git a/polls/views.py b/polls/views.py
index 3cd85c0..bcdf518 100644
--- a/polls/views.py
+++ b/polls/views.py
@@ -25,7 +25,7 @@ class IndexView(generic.ListView):
             """
             now = timezone.now()
             return Question.objects.filter(
-                Q(pub_date__lte=now) & (Q(end_date__gte=now) | Q(end_date=None))
+                Q(pub_date__lte=now) & ((Q(end_date__gte=now) | Q(end_date=None)))
             ).order_by("-pub_date")
 
 
@@ -42,7 +42,10 @@ class DetailView(LoginRequiredMixin, generic.DetailView):
         """
         Excludes any questions that aren't published yet.
         """
-        return Question.objects.filter(pub_date__lte=timezone.now())
+        now = timezone.now()
+        return Question.objects.filter(
+            Q(pub_date__lte=now) & (Q(end_date__gte=now) | Q(end_date=None))
+        ).order_by("-pub_date")
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
@@ -88,6 +91,7 @@ class SignUpView(generic.CreateView):
     success_url = reverse_lazy('login')
     template_name = 'registration/signup.html'
 
+
 @login_required
 def vote(request, question_id):
     """
@@ -95,29 +99,31 @@ def vote(request, question_id):
     in a specific question_id.
     """
     question = get_object_or_404(Question, pk=question_id)
-    try:
-        selected_choice = question.choice_set.get(pk=request.POST["choice"])
-    except (KeyError, Choice.DoesNotExist):
-        messages.error(request, "You didn't select a choice.")
-        return render(request, "polls/detail.html", {"question": question})
 
-    else:
+    if request.method == "POST":
+        try:
+            selected_choice = question.choice_set.get(pk=request.POST["choice"])
+        except (KeyError, Choice.DoesNotExist):
+            messages.error(request, "You didn't select a choice.")
+            return redirect("polls:detail", question_id)
+
         if question.can_vote():
-            if request.method == "POST" and "vote-button" in request.POST:
-                if Vote.objects.filter(user=request.user, question=question).exists():
-                    old_vote = question.vote_set.get(user=request.user)
-                    old_vote.choice = selected_choice
-                    old_vote.save()
+            # ! Return 1. object element 2. boolean status of creation
+            vote, created = Vote.objects.update_or_create(
+                user=request.user,
+                question=question,
+                defaults={'choice' : selected_choice}
+            )
 
-                    messages.success(request, "You vote successfully🥳")
-                    return HttpResponseRedirect(reverse("polls:results", args=(question.id,)))
-                else:
-                    Vote.objects.create(choice=selected_choice, user=request.user, question=question).save()
-                    messages.success(request, "You vote successfully🥳")
-                    return HttpResponseRedirect(reverse("polls:results", args=(question.id,)))
+            if created:
+                messages.success(request, "You voted successfully🥳")
             else:
-                messages.error(request, "You cannot vote by typing the URL.")
-                return render(request, "polls/detail.html", {"question": question})
+                messages.success(request, "You updated your vote🥳")
+
+            return redirect("polls:results", question_id)
         else:
-            messages.error(request, "You can not vote on this question.")
-            return HttpResponseRedirect(reverse("polls:index"))
\ No newline at end of file
+            messages.error(request, "You cannot vote on this question.")
+            return redirect("polls:index")
+    else:
+        messages.error(request, "Invalid request method.")
+        return redirect("polls:index")
\ No newline at end of file