diff --git a/Palto/Palto/models.py b/Palto/Palto/models.py
index d695988..782ae06 100644
--- a/Palto/Palto/models.py
+++ b/Palto/Palto/models.py
@@ -543,7 +543,7 @@ class TeachingSession(models.Model, ModelPermissionHelper):
         """
 
         return Absence.objects.filter(
-            student__in=self.group.students,
+            student__in=self.group.students.all(),
             start__lte=self.start, end__gte=self.end
         ).distinct()
 
diff --git a/Palto/Palto/static/Palto/css/base.css b/Palto/Palto/static/Palto/css/base.css
index 9830d27..0d09586 100644
--- a/Palto/Palto/static/Palto/css/base.css
+++ b/Palto/Palto/static/Palto/css/base.css
@@ -1,15 +1,47 @@
-/* tweaks */
-body {
-    margin: 0;
-}
-
 /* font */
 * {
     font-family: "Century Gothic", sans-serif;
 }
 
+/* color-scheme */
+@media (prefers-color-scheme: light) {
+    :root {
+        --primary: #00345F;
+        --secondary: #EF800A;
+
+        --foreground: #1B1B1B;
+        --background: #FFFFFF;
+    }
+}
+
+@media (prefers-color-scheme: dark) {
+    :root {
+        --primary: #00549F;
+        --secondary: #EF800A;
+
+        --foreground: #FFFFFF;
+        --background: #1B1B1B;
+    }
+}
+
 /* links */
 *:link, *:visited {
-    color: blue;  /* TODO: should be palette based color */
+    color: var(--primary);
     text-decoration: none;
 }
+
+*:link:hover, *:visited:hover {
+    color: var(--secondary);
+}
+
+/* table */
+table, tr, th, td {
+    border-color: var(--foreground) !important;
+}
+
+/* tweaks */
+body {
+    margin: 0;
+    color: var(--foreground);
+    background-color: var(--background);
+}
\ No newline at end of file
diff --git a/Palto/Palto/static/Palto/css/department_view.css b/Palto/Palto/static/Palto/css/table_view.css
similarity index 64%
rename from Palto/Palto/static/Palto/css/department_view.css
rename to Palto/Palto/static/Palto/css/table_view.css
index cfb6dcb..085f09f 100644
--- a/Palto/Palto/static/Palto/css/department_view.css
+++ b/Palto/Palto/static/Palto/css/table_view.css
@@ -1,39 +1,34 @@
-#department-informations {
+#table-informations {
     border-collapse: collapse;
     border: 2px solid black;
     margin: 5% auto;
 }
 
-#department-informations th {
+#table-informations th {
     text-align: right;
     border: 1px solid black;
     padding: 4px;
 }
 
-#department-informations td {
+#table-informations td {
     text-align: left;
     border: 1px solid black;
     padding: 4px;
 }
 
-#department-relations {
+#table-relations {
     display: flex;
     width: 60%;
     margin: auto;
 }
 
-.department-relation {
+.table-relation {
     border-collapse: collapse;
     border: 2px solid black;
     margin: 0 auto auto auto;
 }
 
-.department-relation th {
+.table-relation th, .table-relation td {
     border: 2px solid black;
     padding: 4px;
 }
-
-.department-relation td {
-    border: 2px solid black;
-    padding: 4px;
-}
\ No newline at end of file
diff --git a/Palto/Palto/templates/Palto/department_view.html b/Palto/Palto/templates/Palto/department_view.html
index 43a2563..3e69b13 100644
--- a/Palto/Palto/templates/Palto/department_view.html
+++ b/Palto/Palto/templates/Palto/department_view.html
@@ -12,14 +12,14 @@
 
 {% block style %}
     {{ block.super }}
-    <link rel="stylesheet" href="{% static "Palto/css/department_view.css" %}" />
+    <link rel="stylesheet" href="{% static "Palto/css/table_view.css" %}" />
 {% endblock %}
 
 {% block body %}
     {{ block.super }}
 
     {# department's information #}
-    <table id="department-informations">
+    <table id="table-informations">
         <tr>
             <th>Identifiant</th>
             <td>{{ department.id }}</td>
@@ -42,9 +42,9 @@
         </tr>
     </table>
 
-    <div id="department-relations">
+    <div id="table-relations">
         {# department's managers #}
-        <table class="department-relation">
+        <table class="table-relation">
             <thead>
                 <tr>
                     <th>Responsables</th>
@@ -60,7 +60,7 @@
         </table>
 
         {# department's teachers #}
-        <table class="department-relation">
+        <table class="table-relation">
             <thead>
                 <tr>
                     <th>Enseignants</th>
diff --git a/Palto/Palto/templates/Palto/student_group.html b/Palto/Palto/templates/Palto/student_group.html
index a5c0b1a..8d538fa 100644
--- a/Palto/Palto/templates/Palto/student_group.html
+++ b/Palto/Palto/templates/Palto/student_group.html
@@ -1,4 +1,5 @@
 {% extends "Palto/base/base-features.html" %}
+{% load static %}
 
 {% block page-title %}
     Groupe Étudiant {{ group.name }}
@@ -8,11 +9,16 @@
     Groupe Étudiant {{ group.name }}
 {% endblock %}
 
+{% block style %}
+    {{ block.super }}
+    <link rel="stylesheet" href="{% static "Palto/css/table_view.css" %}" />
+{% endblock %}
+
 {% block body %}
     {{ block.super }}
 
     {# group's information #}
-    <table>
+    <table id="table-informations">
         <tr>
             <th>Identifiant</th>
             <td>{{ group.id }}</td>
@@ -31,19 +37,21 @@
         </tr>
     </table>
 
-    {# group's students information #}
-    <table>
-        <thead>
-            <tr>
-                <th>Étudiants</th>
-            </tr>
-        </thead>
-        <tbody>
-            {% for student in group.students.all %}
+    <div id="table-relations">
+        {# group's students information #}
+        <table class="table-relation">
+            <thead>
                 <tr>
-                    <td><a href="{% url "Palto:profile" student.id %}">{{ student }}</a></td>
+                    <th>Étudiants</th>
                 </tr>
-            {% endfor %}
-        </tbody>
-    </table>
+            </thead>
+            <tbody>
+                {% for student in group.students.all %}
+                    <tr>
+                        <td><a href="{% url "Palto:profile" student.id %}">{{ student }}</a></td>
+                    </tr>
+                {% endfor %}
+            </tbody>
+        </table>
+    </div>
 {% endblock %}
diff --git a/Palto/Palto/templates/Palto/teaching_session_view.html b/Palto/Palto/templates/Palto/teaching_session_view.html
index 290ecbd..3a0dbc3 100644
--- a/Palto/Palto/templates/Palto/teaching_session_view.html
+++ b/Palto/Palto/templates/Palto/teaching_session_view.html
@@ -1,5 +1,6 @@
 {% extends "Palto/base/base-features.html" %}
 {% load dict_tags %}
+{% load static %}
 
 {% block page-title %}
     Session de {{ session.unit.name }}
@@ -9,11 +10,16 @@
     Session de {{ session.unit.name }}
 {% endblock %}
 
+{% block style %}
+    {{ block.super }}
+    <link rel="stylesheet" href="{% static "Palto/css/table_view.css" %}" />
+{% endblock %}
+
 {% block body %}
     {{ block.super }}
 
     {# session's information #}
-    <table>
+    <table id="table-informations">
         <tr>
             <th>Identifiant</th>
             <td>{{ session.id }}</td>
@@ -39,38 +45,40 @@
             <td><a href="{% url "Palto:student_group_view" session.group.id %}">{{ session.group }}</a></td>
         </tr>
     </table>
-
-    {# session's students information #}
-    <table>
-        <thead>
-            <tr>
-                <th>Elève</th>
-                <th>Présence</th>
-                <th>Absence</th>
-            </tr>
-        </thead>
-        <tbody>
-            {% for student, session_student_data in session_students_data.items %}
+    
+    <div id="table-relations">
+        {# session's students information #}
+        <table class="table-relation">
+            <thead>
                 <tr>
-                    <td><a href="{% url "Palto:profile" student.id %}">{{ student }}</a></td>
-                    <td>
-                        {% with attendance=session_student_data|dict_get:"attendance" %}
-                            {% if attendance != None %}
-                                {{ attendance.date }}
-                            {% endif %}
-                        {% endwith %}
-                    </td>
-                    <td>
-                        {% with absence=session_student_data|dict_get:"absence" %}
-                            {% if absence != None %}
-                                <a href="{% url "Palto:absence_view" absence.id %}">Détails</a>
-                            {% endif %}
-                        {% endwith %}
-                    </td>
+                    <th>Elève</th>
+                    <th>Présence</th>
+                    <th>Absence</th>
                 </tr>
-            {% endfor %}
-        </tbody>
-    </table>
-
+            </thead>
+            <tbody>
+                {% for student, session_student_data in session_students_data.items %}
+                    <tr>
+                        <td><a href="{% url "Palto:profile" student.id %}">{{ student }}</a></td>
+                        <td>
+                            {% with attendance=session_student_data|dict_get:"attendance" %}
+                                {% if attendance != None %}
+                                    {{ attendance.date }}
+                                {% endif %}
+                            {% endwith %}
+                        </td>
+                        <td>
+                            {% with absence=session_student_data|dict_get:"absence" %}
+                                {% if absence != None %}
+                                    <a href="{% url "Palto:absence_view" absence.id %}">Détails</a>
+                                {% endif %}
+                            {% endwith %}
+                        </td>
+                    </tr>
+                {% endfor %}
+            </tbody>
+        </table>
+    </div>
+    
     {# TODO(Raphaël): export boutton #}
 {% endblock %}
diff --git a/Palto/Palto/templates/Palto/teaching_unit_view.html b/Palto/Palto/templates/Palto/teaching_unit_view.html
index 491b624..00a9df9 100644
--- a/Palto/Palto/templates/Palto/teaching_unit_view.html
+++ b/Palto/Palto/templates/Palto/teaching_unit_view.html
@@ -1,5 +1,6 @@
 {% extends "Palto/base/base-features.html" %}
 {% load dict_tags %}
+{% load static %}
 
 {% block page-title %}
     Unité d'Enseignement de {{ unit.name }}
@@ -9,11 +10,16 @@
     Unité d'Enseignement de {{ unit.name }}
 {% endblock %}
 
+{% block style %}
+    {{ block.super }}
+    <link rel="stylesheet" href="{% static "Palto/css/table_view.css" %}" />
+{% endblock %}
+
 {% block body %}
     {{ block.super }}
 
     {# unit's information #}
-    <table>
+    <table id="table-informations">
         <tr>
             <th>Identifiant</th>
             <td>{{ unit.id }}</td>
@@ -24,7 +30,7 @@
         </tr>
         <tr>
             <th>Département</th>
-            <td href="{% url "Palto:department_view" unit.department.id %}">{{ unit.department.name }}</td>
+            <td><a href="{% url "Palto:department_view" unit.department.id %}">{{ unit.department.name }}</a></td>
         </tr>
         <tr>
             <th>Mail</th>
@@ -36,35 +42,37 @@
         </tr>
     </table>
 
-    {# unit's managers #}
-    <table>
-        <thead>
-            <tr>
-                <th>Responsables</th>
-            </tr>
-        </thead>
-        <tbody>
-            {% for manager in unit.managers.all %}
+    <div id="table-relations">
+        {# unit's managers #}
+        <table class="table-relation">
+            <thead>
                 <tr>
-                    <td><a href="{% url "Palto:profile" manager.id %}">{{ manager }}</a></td>
+                    <th>Responsables</th>
                 </tr>
-            {% endfor %}
-        </tbody>
-    </table>
-
-    {# unit's teachers #}
-    <table>
-        <thead>
-            <tr>
-                <th>Enseignants</th>
-            </tr>
-        </thead>
-        <tbody>
-            {% for teacher in unit.teachers.all %}
+            </thead>
+            <tbody>
+                {% for manager in unit.managers.all %}
+                    <tr>
+                        <td><a href="{% url "Palto:profile" manager.id %}">{{ manager }}</a></td>
+                    </tr>
+                {% endfor %}
+            </tbody>
+        </table>
+    
+        {# unit's teachers #}
+        <table class="table-relation">
+            <thead>
                 <tr>
-                    <td><a href="{% url "Palto:profile" teacher.id %}">{{ teacher }}</a></td>
+                    <th>Enseignants</th>
                 </tr>
-            {% endfor %}
-        </tbody>
-    </table>
+            </thead>
+            <tbody>
+                {% for teacher in unit.teachers.all %}
+                    <tr>
+                        <td><a href="{% url "Palto:profile" teacher.id %}">{{ teacher }}</a></td>
+                    </tr>
+                {% endfor %}
+            </tbody>
+        </table>
+    </div>
 {% endblock %}