diff --git a/bureau/content_page.py b/bureau/content_page.py
index aa22fea..2758647 100644
--- a/bureau/content_page.py
+++ b/bureau/content_page.py
@@ -21,18 +21,36 @@
 # SOFTWARE.
 #
 # SPDX-License-Identifier: MIT
-
-
-from gi.repository import Gtk
+import inject
+from gi.repository import Gtk, GObject, Adw
 
 from bureau.components.sidebar.column import SidebarColumn
+from bureau.providers.app_state import AppStateProvider
 
 
 @Gtk.Template(resource_path='/com/tenderowl/bureau/ui/content_page.ui')
 class ContentPage(Gtk.Box):
     __gtype_name__ = 'ContentPage'
 
+    outer: Adw.OverlaySplitView = Gtk.Template.Child()
     sidebar_column: SidebarColumn = Gtk.Template.Child()
+    toggle_sidebar_btn: Gtk.ToggleButton = Gtk.Template.Child()
+
+    app_state: AppStateProvider
 
-    def __init__(self, **kwargs):
+    @inject.autoparams()
+    def __init__(self, app_state: AppStateProvider, **kwargs):
         super().__init__(**kwargs)
+        self.app_state = app_state
+
+        self.app_state.bind_property('sidebar_collapsed', self.outer, 'collapsed', GObject.BindingFlags.BIDIRECTIONAL)
+        self.toggle_sidebar_btn.bind_property('visible', self.app_state, 'sidebar_collapsed',
+                                              GObject.BindingFlags.BIDIRECTIONAL)
+        self.toggle_sidebar_btn.bind_property('active', self.outer, 'show-sidebar', GObject.BindingFlags.BIDIRECTIONAL)
+        # self.sidebar_column.connect('notify::show-sidebar', self._on_sidebar_collapsed)
+
+    # @Gtk.Template.Callback()
+    # def _on_sidebar_collapsed(self, state: bool):
+    #     print('Collapsed ', state)
+    #     self.app_state.sidebar_collapsed = state
+    #     self.toggle_sidebar_btn.set_visible(state)
diff --git a/bureau/main.py b/bureau/main.py
index d631c7b..e399356 100644
--- a/bureau/main.py
+++ b/bureau/main.py
@@ -35,12 +35,14 @@
 
 from .window import BureauWindow
 from bureau.providers.account import AccountProvider
+from bureau.providers.app_state import AppStateProvider
 from bureau.providers.imap import ImapProvider
 
 
 def configure_providers(binder: inject.Binder):
     binder.bind(ImapProvider, ImapProvider('imap.yandex.ru'))
     binder.bind(AccountProvider, AccountProvider())
+    binder.bind(AppStateProvider, AppStateProvider())
 
 
 class BureauApplication(Adw.Application):
@@ -74,12 +76,12 @@ def do_activate(self):
     def on_about_action(self, widget, _):
         """Callback for the app.about action."""
         about = Adw.AboutWindow(transient_for=self.props.active_window,
-                                application_name='bureau',
+                                application_name='Bureau',
                                 application_icon='com.tenderowl.bureau',
                                 developer_name='TenderOwl',
                                 version=self.version or '0.1.0',
                                 developers=['Andrey Maksimov'],
-                                copyright='© 2023 Andrey Maksimov')
+                                copyright='© 2023 TenderOwl')
         about.present()
 
     def on_preferences_action(self, widget, _):
diff --git a/bureau/providers/app_state.py b/bureau/providers/app_state.py
new file mode 100644
index 0000000..76eb07b
--- /dev/null
+++ b/bureau/providers/app_state.py
@@ -0,0 +1,17 @@
+from gi.repository import GObject
+
+
+class AppStateProvider(GObject.GObject):
+    __gtype_name__ = "AppStateProvider"
+
+    # Props
+    sidebar_collapsed = GObject.Property(type=bool, default=True)
+    mail_column_collapsed = GObject.Property(type=bool, default=True)
+
+    # Signals
+    __gsignals__ = {
+        'sidebar-changed': (GObject.SIGNAL_RUN_FIRST, None, (bool,))
+    }
+
+    def __init__(self):
+        super().__init__()
diff --git a/data/ui/content_page.blp b/data/ui/content_page.blp
index 70c7d2c..5a8c366 100644
--- a/data/ui/content_page.blp
+++ b/data/ui/content_page.blp
@@ -30,7 +30,7 @@ template $ContentPage : Box {
 
           Adw.NavigationSplitView inner {
             min-sidebar-width: 360;
-            max-sidebar-width: 600;
+            max-sidebar-width: 500;
             sidebar-width-fraction: 0.40;
 
             sidebar: Adw.NavigationPage {
@@ -43,6 +43,12 @@ template $ContentPage : Box {
                 [top]
                 Adw.HeaderBar {
                   show-title: false;
+
+                  ToggleButton toggle_sidebar_btn {
+                    icon-name: "sidebar-show-symbolic";
+                    tooltip-text: "Toggle Sidebar";
+                    visible: false;
+                  }
                 }
               }
             };