Index: wp-content/themes/twentytwelve/style.css
===================================================================
--- wp-content/themes/twentytwelve/style.css	(revisão 21626)
+++ wp-content/themes/twentytwelve/style.css	(cópia de trabalho)
@@ -434,10 +434,13 @@
 body {
 	font-size: 14px;
 	font-size: 1rem;
-	font-family: "Open Sans", Helvetica, Arial, sans-serif;
+	font-family: Helvetica, Arial, sans-serif;
 	text-rendering: optimizeLegibility;
 	color: #444;
 }
+body.enable-fonts {
+	font-family: "Open Sans", Helvetica, Arial, sans-serif;
+}
 a {
 	outline: none;
 	color: #21759b;
Index: wp-content/themes/twentytwelve/functions.php
===================================================================
--- wp-content/themes/twentytwelve/functions.php	(revisão 21626)
+++ wp-content/themes/twentytwelve/functions.php	(cópia de trabalho)
@@ -370,6 +370,7 @@
  * @return array Filtered class values.
  */
 function twentytwelve_body_class( $classes ) {
+	global $twentytwelve_options;
 	$background_color = get_background_color();

 	if ( ! is_active_sidebar( 1 ) || is_page_template( 'full-width-page.php' ) )
@@ -383,6 +384,10 @@
 	elseif ( in_array( $background_color, array( 'fff', 'ffffff' ) ) )
 		$classes[] = 'custom-background-white';

+	$options = $twentytwelve_options->get_theme_options();
+	if ( $options['enable_fonts'] )
+ 		$classes[] = 'enable-fonts';
+
 	return $classes;
 }
 add_filter( 'body_class', 'twentytwelve_body_class' );