setttings button visually added along with other cosmetic changes

Makefile

@@ -4,7 +4,7 @@ DATADIR ?= $(PREFIX)/share
 CONFDIR = /etc
 
 install:
-	sed "s/%DATADIR%/\/usr\/share/" lightdm-mobile-greeter.py > lightdm-mobile-greeter
+	sed "s#%DATADIR%#$(DATADIR)#" lightdm-mobile-greeter.py > lightdm-mobile-greeter
 	install -Dm755 lightdm-mobile-greeter -t $(DESTDIR)$(BINDIR)
 	install -Dm644 style.css interface.ui -t $(DESTDIR)$(DATADIR)/lightdm-mobile-greeter
 	install -Dm644 lightdm-mobile-greeter.desktop -t $(DESTDIR)$(DATADIR)/xgreeters

interface.ui

@@ -53,6 +53,7 @@
                     <property name="only_digits">True</property>
                     <property name="show_symbols">False</property>
                     <property name="right_action">delete_btn</property>
+                    <property name="left_action">settings_btn</property>
                     <property name="entry">pin_entry</property>
                     <style>
                       <class name="keypad"/>
@@ -79,7 +80,7 @@
                 <child>
                   <object class="GtkLabel" id="message_label">
                       <property name="visible">True</property>
-                      <property name="label">message label</property>
+                      <property name="label"></property>
                   </object>
                 </child>
               </object>
@@ -99,6 +100,20 @@
       <object class="GtkImage">
         <property name="visible">True</property>
         <property name="icon_name">edit-clear-symbolic</property>
+        <property name="icon_size">40</property>
+      </object>
+    </child>
+  </object>
+  <object class="GtkButton" id="settings_btn">
+    <property name="visible">True</property>
+    <property name="can_focus">True</property>
+    <property name="focus-on-click">False</property>
+    <signal name="clicked" handler="backspace"/>
+    <child>
+      <object class="GtkImage">
+        <property name="visible">True</property>
+        <property name="icon_name">applications-system-symbolic</property>
+        <property name="icon_size">40</property>
       </object>
     </child>
   </object>

style.css

@@ -17,9 +17,7 @@ button {
     border-width: 2px;
     padding: 16px 36px;
 }
-.keypad button {
+
-    padding: 16px 16px;
-}
 label {
     font-weight: bold;
 }
@@ -32,3 +30,10 @@ button:active {
 button:active label {
     color: black;
 }
+
+hdykeypad > button {
+   font-size: 20px;
+   font-weight: bold;
+   padding: 10px;
+}
+