Index: gnome-shell-3.26.0/data/gnome-shell-theme.gresource.xml
===================================================================
--- gnome-shell-3.26.0.orig/data/gnome-shell-theme.gresource.xml
+++ gnome-shell-3.26.0/data/gnome-shell-theme.gresource.xml
@@ -38,5 +38,6 @@
     <file>toggle-on-hc.svg</file>
     <file>ws-switch-arrow-up.png</file>
     <file>ws-switch-arrow-down.png</file>
+    <file>sle-background.png</file>
   </gresource>
 </gresources>
Index: gnome-shell-3.26.0/data/theme/gnome-shell.css
===================================================================
--- gnome-shell-3.26.0.orig/data/theme/gnome-shell.css
+++ gnome-shell-3.26.0/data/theme/gnome-shell.css
@@ -1599,6 +1599,9 @@ StScrollBar {
   padding-top: 24px;
   max-width: 23em; }
 
+.login-dialog-sle {
+  background: #2e3436 url(sle-background.png); }
+
 .login-dialog {
   border: none;
   background-color: transparent; }
Index: gnome-shell-3.26.0/js/ui/unlockDialog.js
===================================================================
--- gnome-shell-3.26.0.orig/js/ui/unlockDialog.js
+++ gnome-shell-3.26.0/js/ui/unlockDialog.js
@@ -37,6 +37,7 @@ var UnlockDialog = new Lang.Class({
                                      layout_manager: new Clutter.BoxLayout(),
                                      visible: false });
 
+        this.actor.add_style_class_name('login-dialog-sle');
         this.actor.add_constraint(new Layout.MonitorConstraint({ primary: true }));
         parentActor.add_child(this.actor);