diff -r 000000000000 -r 6474c204b198 browser/devtools/styleeditor/test/media-small.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/styleeditor/test/media-small.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,5 @@
+/* this stylesheet applies when min-width<400px */
+body {
+	background: red;
+}
+