Index: wp-content/themes/twentyeleven/style.css
===================================================================
--- wp-content/themes/twentyeleven/style.css	(revision 21103)
+++ wp-content/themes/twentyeleven/style.css	(working copy)
@@ -530,7 +530,7 @@
 }
 #branding img {
 	height: auto;
-	margin-bottom: -7px;
+	display: block;
 	width: 100%;
 }