Style first screen "choose nickname"

src/window.py

@@ -23,8 +23,6 @@ from .gi_composites import GtkTemplate
 class BriarGtkWindow(Gtk.ApplicationWindow):
     __gtype_name__ = 'BriarGtkWindow'
 
-    label = GtkTemplate.Child()
-
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         self.init_template()

src/window.ui

@@ -12,16 +12,51 @@
       </object>
     </child>
     <child>
-      <object class="GtkLabel" id="label">
-        <property name="label">Secure messaging, anywhere.</property>
+      <object class="GtkGrid">
         <property name="visible">True</property>
-        <attributes>
-          <attribute name="weight" value="bold"/>
-          <attribute name="scale" value="2"/>
-        </attributes>
+        <property name="can_focus">False</property>
+        <property name="halign">center</property>
+        <property name="valign">center</property>
+        <property name="margin_left">18</property>
+        <property name="margin_right">18</property>
+        <property name="margin_top">18</property>
+        <property name="margin_bottom">18</property>
+        <property name="row_spacing">6</property>
+        <property name="column_spacing">12</property>
+        <child>
+          <object class="GtkLabel" id="username-label">
+            <property name="visible">True</property>
+            <property name="halign">center</property>
+            <property name="label" translatable="yes">Nickname</property>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="username">
+            <property name="visible">True</property>
+            <property name="placeholder_text" translatable="yes">Choose your nickname</property>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="username-next">
+            <property name="visible">True</property>
+            <property name="halign">center</property>
+            <property name="label" translatable="yes">Next</property>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">2</property>
+          </packing>
+        </child>
       </object>
     </child>
   </template>
 </interface>
 
-