diff --git a/themes/atom-dark-ui/package.cson b/themes/atom-dark-ui/package.cson
index 53831688d..7aa632dc4 100644
--- a/themes/atom-dark-ui/package.cson
+++ b/themes/atom-dark-ui/package.cson
@@ -1,11 +1,11 @@
 'stylesheets': [
-  'atom.css'
-  'editor.css'
-  'select-list.css'
-  'tree-view.css'
-  'tabs.css'
-  'status-bar.css'
-  'command-panel.css'
-  'command-logger.css'
-  'blurred.css'
+  'atom'
+  'editor'
+  'select-list'
+  'tree-view'
+  'tabs'
+  'status-bar'
+  'command-panel'
+  'command-logger'
+  'blurred'
 ]
diff --git a/themes/atom-light-ui/package.cson b/themes/atom-light-ui/package.cson
index 18cff697d..7f3d899c5 100644
--- a/themes/atom-light-ui/package.cson
+++ b/themes/atom-light-ui/package.cson
@@ -1,12 +1,12 @@
 'stylesheets': [
-  'atom.css'
-  'editor.css'
-  'overlay.css'
-  'select-list.css'
-  'tree-view.css'
-  'tabs.css'
-  'status-bar.css'
-  'command-panel.css'
-  'command-logger.css'
-  'blurred.css'
+  'atom'
+  'editor'
+  'overlay'
+  'select-list'
+  'tree-view'
+  'tabs'
+  'status-bar'
+  'command-panel'
+  'command-logger'
+  'blurred'
 ]