diff --git a/pgp/gtk/choose_key.ui b/pgp/gtk/choose_key.ui
index 37decf8..8e91fce 100644
--- a/pgp/gtk/choose_key.ui
+++ b/pgp/gtk/choose_key.ui
@@ -11,9 +11,11 @@
     </columns>
   </object>
   <object class="GtkBox" id="box">
+    <property name="width_request">500</property>
+    <property name="height_request">300</property>
     <property name="visible">True</property>
     <property name="can_focus">False</property>
-    <property name="border_width">6</property>
+    <property name="border_width">18</property>
     <property name="orientation">vertical</property>
     <property name="spacing">6</property>
     <child>
@@ -62,7 +64,7 @@
       <packing>
         <property name="expand">True</property>
         <property name="fill">True</property>
-        <property name="position">1</property>
+        <property name="position">0</property>
       </packing>
     </child>
   </object>
diff --git a/pgp/gtk/config.py b/pgp/gtk/config.py
index cd0ef74..d806b03 100644
--- a/pgp/gtk/config.py
+++ b/pgp/gtk/config.py
@@ -18,6 +18,7 @@ from pathlib import Path
 
 from gi.repository import Gtk
 from gi.repository import Gdk
+from gi.repository import GLib
 
 from gajim.common import app
 
@@ -64,6 +65,9 @@ class Page(Gtk.Box):
         self._plugin = plugin
         self._label = Gtk.Label()
         self._button = Gtk.Button(label=_('Assign Key'))
+        self._button.get_style_context().add_class('suggested-action')
+        self._button.set_halign(Gtk.Align.CENTER)
+        self._button.set_margin_top(18)
         self._button.connect('clicked', self._on_assign)
 
         self._load_key()
@@ -101,4 +105,5 @@ class Page(Gtk.Box):
             self._label.set_text(_('No key assigned'))
         else:
             key_id, key_user = key_data
-            self._label.set_text('%s %s' % (key_id, key_user))
+            self._label.set_markup('<b><tt>%s</tt> %s</b>' % \
+                (key_id, GLib.markup_escape_text(key_user)))
diff --git a/pgp/gtk/config.ui b/pgp/gtk/config.ui
index c09c849..bdafb29 100644
--- a/pgp/gtk/config.ui
+++ b/pgp/gtk/config.ui
@@ -3,8 +3,6 @@
 <interface>
   <requires lib="gtk+" version="3.20"/>
   <object class="GtkBox" id="config_box">
-    <property name="width_request">500</property>
-    <property name="height_request">400</property>
     <property name="visible">True</property>
     <property name="can_focus">False</property>
     <property name="spacing">12</property>
@@ -22,8 +20,12 @@
     </child>
     <child>
       <object class="GtkStack" id="stack">
+        <property name="width_request">400</property>
+        <property name="height_request">350</property>
         <property name="visible">True</property>
         <property name="can_focus">False</property>
+        <property name="hexpand">True</property>
+        <property name="border_width">18</property>
         <property name="transition_type">crossfade</property>
         <child>
           <placeholder/>
diff --git a/pgp/gtk/key.py b/pgp/gtk/key.py
index 10e360c..64827fb 100644
--- a/pgp/gtk/key.py
+++ b/pgp/gtk/key.py
@@ -17,6 +17,7 @@
 from pathlib import Path
 
 from gi.repository import Gtk
+from gi.repository import GLib
 
 from gajim.common import app
 from gajim.plugins.plugins_i18n import _
@@ -30,7 +31,7 @@ class KeyDialog(Gtk.Dialog):
 
         self.set_transient_for(transient)
         self.set_resizable(True)
-        self.set_default_size(500, 300)
+        self.set_default_size(450, -1)
 
         self._plugin = plugin
         self._jid = jid
@@ -38,10 +39,14 @@ class KeyDialog(Gtk.Dialog):
 
         self._label = Gtk.Label()
 
-        self._assign_button = Gtk.Button(label='assign')
+        self._assign_button = Gtk.Button(label=_('Assign Key'))
+        self._assign_button.get_style_context().add_class('suggested-action')
+        self._assign_button.set_halign(Gtk.Align.CENTER)
+        self._assign_button.set_margin_top(18)
         self._assign_button.connect('clicked', self._choose_key)
 
         box = Gtk.Box(orientation=Gtk.Orientation.VERTICAL)
+        box.set_border_width(18)
         box.add(self._label)
         box.add(self._assign_button)
 
@@ -82,7 +87,8 @@ class KeyDialog(Gtk.Dialog):
             self._label.set_text(_('No key assigned'))
         else:
             key_id, key_user = key_data
-            self._label.set_text('%s %s' % (key_id, key_user))
+            self._label.set_markup('<b><tt>%s</tt> %s</b>' % \
+                (key_id, GLib.markup_escape_text(key_user)))
 
 
 class ChooseGPGKeyDialog(Gtk.Dialog):
@@ -97,8 +103,8 @@ class ChooseGPGKeyDialog(Gtk.Dialog):
         self.set_resizable(True)
         self.set_default_size(500, 300)
 
-        self.add_button(_('OK'), Gtk.ResponseType.OK)
         self.add_button(_('Cancel'), Gtk.ResponseType.CANCEL)
+        self.add_button(_('OK'), Gtk.ResponseType.OK)
 
         self._selected_key = None