Index: src/wp-admin/css/install.css
===================================================================
--- src/wp-admin/css/install.css	(revision 28604)
+++ src/wp-admin/css/install.css	(working copy)
@@ -68,8 +68,8 @@
 #logo a {
 	background-image: url(../images/w-logo-blue.png?ver=20131202);
 	background-image: none, url(../images/wordpress-logo.svg?ver=20131107);
-	-webkit-background-size: 80px 80px;
-	background-size: 80px 80px;
+	-webkit-background-size: 78px 78px;
+	background-size: 78px 78px;
 	background-position: center top;
 	background-repeat: no-repeat;
 	color: #999;
Index: src/wp-admin/css/login.css
===================================================================
--- src/wp-admin/css/login.css	(revision 28604)
+++ src/wp-admin/css/login.css	(working copy)
@@ -126,8 +126,8 @@
 .login h1 a {
 	background-image: url(../images/w-logo-blue.png?ver=20131202);
 	background-image: none, url(../images/wordpress-logo.svg?ver=20131107);
-	-webkit-background-size: 80px 80px;
-	background-size: 80px 80px;
+	-webkit-background-size: 78px 78px;
+	background-size: 78px 78px;
 	background-position: center top;
 	background-repeat: no-repeat;
 	color: #999;