Index: wp-content/themes/twentytwelve/style.css
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- wp-content/themes/twentytwelve/style.css	(revision 21271)
+++ wp-content/themes/twentytwelve/style.css	(revision )
@@ -882,6 +882,7 @@
 	font-size: 0.857142857rem;
 	line-height: 2;
 	overflow: auto;
+	background-color: #F4F8FA;
 }
 .entry-content pre code {
 	display: block;
\ No newline at end of file