Index: wp-content/themes/twentytwelve/header.php
===================================================================
--- wp-content/themes/twentytwelve/header.php	(revision 20037)
+++ wp-content/themes/twentytwelve/header.php	(working copy)
@@ -24,7 +24,8 @@
 if ( is_singular() && comments_open() && get_option( 'thread_comments' ) )
 	wp_enqueue_script( 'comment-reply' );
 
-wp_enqueue_style( 'fonts', 'http://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,400,300,600,700' );
+$scheme = is_ssl() ? 'https' : 'http';
+wp_enqueue_style( 'fonts', $scheme . '://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,400,300,600,700' );
 
 wp_enqueue_style( 'twentytwelve-style', get_stylesheet_uri() );
 ?>
@@ -51,4 +52,4 @@
 		<?php endif; ?>
 	</header><!-- #masthead -->
 
-	<div id="main">
\ No newline at end of file
+	<div id="main">