diff --git a/core/modules/system/src/Tests/Menu/MenuRouterTest.php b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
index 5782b0a..4089931 100644
--- a/core/modules/system/src/Tests/Menu/MenuRouterTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
@@ -306,6 +306,7 @@ protected function doTestThemeCallbackOptionalTheme() {
 
     $this->drupalGet('menu-test/theme-callback/use-stark-theme');
     $this->assertText('Active theme: stark. Actual theme: stark.', 'The theme negotiation system uses an optional theme once it has been installed.');
+    $this->assertRaw('stark/css/layout.css', "The optional theme's CSS appears on the page.");
 
     $theme_handler->uninstall(array('stark'));
   }
diff --git a/core/themes/stark/css/layout.css b/core/themes/stark/css/layout.css
new file mode 100644
index 0000000..e69de29
diff --git a/core/themes/stark/stark.info.yml b/core/themes/stark/stark.info.yml
index 1974272..cda5c0d 100644
--- a/core/themes/stark/stark.info.yml
+++ b/core/themes/stark/stark.info.yml
@@ -1,6 +1,8 @@
 name: Stark
 type: theme
-description: 'An intentionally plain theme with no styling to demonstrate default Drupal’s HTML and CSS. Learn how to build a custom theme from Stark in the <a href="http://drupal.org/theme-guide">Theming Guide</a>.'
+description: 'An intentionally plain theme with almost no styling to demonstrate default Drupal’s HTML and CSS. Learn how to build a custom theme from Stark in the <a href="http://drupal.org/theme-guide">Theming Guide</a>.'
 package: Core
 version: VERSION
 core: 8.x
+libraries:
+  - stark/global-styling
diff --git a/core/themes/stark/stark.libraries.yml b/core/themes/stark/stark.libraries.yml
new file mode 100644
index 0000000..7655147
--- /dev/null
+++ b/core/themes/stark/stark.libraries.yml
@@ -0,0 +1,5 @@
+global-styling:
+  version: VERSION
+  css:
+    base:
+      css/layout.css: {}