Index: wp-content/themes/twentyeleven/style.css
===================================================================
--- wp-content/themes/twentyeleven/style.css	(revision 20500)
+++ wp-content/themes/twentyeleven/style.css	(working copy)
@@ -1838,6 +1838,8 @@
 
 /* Widget Image */
 .widget_image img {
+	border: 0;
+	padding: 0;
 	height: auto;
 	max-width: 100%;
 }