Index: wp-includes/class-wp-customize-section.php
===================================================================
--- wp-includes/class-wp-customize-section.php	(revision 23401)
+++ wp-includes/class-wp-customize-section.php	(working copy)
@@ -79,9 +79,9 @@
 	 */
 	protected function render() {
 		?>
-		<li id="customize-section-<?php echo esc_attr( $this->id ); ?>" class="control-section customize-section">
-			<h3 class="customize-section-title" tabindex="0" title="<?php echo esc_attr( $this->description ); ?>"><?php echo esc_html( $this->title ); ?></h3>
-			<ul class="customize-section-content">
+		<li id="accordion-section-<?php echo esc_attr( $this->id ); ?>" class="control-section accordion-section">
+			<h3 class="accordion-section-title" tabindex="0" title="<?php echo esc_attr( $this->description ); ?>"><?php echo esc_html( $this->title ); ?></h3>
+			<ul class="accordion-section-content">
 				<?php
 				foreach ( $this->controls as $control )
 					$control->maybe_render();
Index: wp-includes/script-loader.php
===================================================================
--- wp-includes/script-loader.php	(revision 23401)
+++ wp-includes/script-loader.php	(working copy)
@@ -107,7 +107,7 @@
 	) );
 
 	$scripts->add( 'autosave', "/wp-includes/js/autosave$suffix.js", array('schedule', 'wp-ajax-response'), false, 1 );
-	
+
 	$scripts->add( 'heartbeat', "/wp-includes/js/heartbeat$suffix.js", array('jquery'), false, 1 );
 	did_action( 'init' ) && $scripts->localize( 'heartbeat', 'heartbeatSettings',
 		apply_filters( 'heartbeat_settings', array() )
@@ -331,6 +331,8 @@
 		'allowedFiles' => __( 'Allowed Files' ),
 	) );
 
+	$scripts->add( 'accordion', "/wp-admin/js/accordion$suffix.js", array( 'jquery' ), false, 1 );
+
 	$scripts->add( 'shortcode', "/wp-includes/js/shortcode$suffix.js", array( 'underscore' ), false, 1 );
 	$scripts->add( 'media-models', "/wp-includes/js/media-models$suffix.js", array( 'backbone', 'jquery' ), false, 1 );
 	did_action( 'init' ) && $scripts->localize( 'media-models', '_wpMediaModelsL10n', array(
Index: wp-admin/customize.php
===================================================================
--- wp-admin/customize.php	(revision 23401)
+++ wp-admin/customize.php	(working copy)
@@ -36,6 +36,8 @@
 wp_enqueue_script( 'customize-controls' );
 wp_enqueue_style( 'customize-controls' );
 
+wp_enqueue_script( 'accordion' );
+
 do_action( 'customize_controls_enqueue_scripts' );
 
 // Let's roll.
@@ -89,15 +91,15 @@
 		?>
 
 		<div class="wp-full-overlay-sidebar-content" tabindex="-1">
-			<div id="customize-info" class="customize-section<?php if ( $cannot_expand ) echo ' cannot-expand'; ?>">
-				<div class="customize-section-title" aria-label="<?php esc_attr_e( 'Theme Customizer Options' ); ?>" tabindex="0">
+			<div id="customize-info" class="accordion-section<?php if ( $cannot_expand ) echo ' cannot-expand'; ?>">
+				<div class="accordion-section-title" aria-label="<?php esc_attr_e( 'Theme Customizer Options' ); ?>" tabindex="0">
 					<span class="preview-notice"><?php
 						/* translators: %s is the theme name in the Customize/Live Preview pane */
 						echo sprintf( __( 'You are previewing %s' ), '<strong class="theme-name">' . $wp_customize->theme()->display('Name') . '</strong>' );
 					?></span>
 				</div>
 				<?php if ( ! $cannot_expand ) : ?>
-				<div class="customize-section-content">
+				<div class="accordion-section-content">
 					<?php if ( $screenshot ) : ?>
 						<img class="theme-screenshot" src="<?php echo esc_url( $screenshot ); ?>" />
 					<?php endif; ?>
Index: wp-admin/js/accordion.js
===================================================================
--- wp-admin/js/accordion.js	(revision 0)
+++ wp-admin/js/accordion.js	(revision 0)
@@ -0,0 +1,21 @@
+jQuery(document).ready( function($) {
+	// Expand/Collapse
+	$('.accordion-section-title').on('click keydown', function( event ) {
+
+		if ( event.type === 'keydown' &&  13 !== event.which ) // enter
+				return;
+
+		var clicked = $( this ).parents( '.accordion-section' );
+
+		if ( clicked.hasClass('cannot-expand') )
+			return;
+
+		// Scroll up if on #accordion-section-title_tagline
+		if ('accordion-section-title_tagline' === clicked.attr('id'))
+			$('.wp-full-overlay-sidebar-content').scrollTop(0);
+
+		$( '.accordion-section' ).not( clicked ).removeClass( 'open' );
+		clicked.toggleClass( 'open' );
+		event.preventDefault();
+	});
+});
\ No newline at end of file
Index: wp-admin/js/customize-controls.js
===================================================================
--- wp-admin/js/customize-controls.js	(revision 23401)
+++ wp-admin/js/customize-controls.js	(working copy)
@@ -846,26 +846,6 @@
 			api.state = state;
 		}());
 
-		// Temporary accordion code.
-		$('.customize-section-title').bind('click keydown', function( event ) {
-
-			if ( event.type === 'keydown' &&  13 !== event.which ) // enter
-					return;
-
-			var clicked = $( this ).parents( '.customize-section' );
-
-			if ( clicked.hasClass('cannot-expand') )
-				return;
-
-			// Scroll up if on #customize-section-title_tagline
-			if ('customize-section-title_tagline' === clicked.attr('id'))
-				$('.wp-full-overlay-sidebar-content').scrollTop(0);
-
-			$( '.customize-section' ).not( clicked ).removeClass( 'open' );
-			clicked.toggleClass( 'open' );
-			event.preventDefault();
-		});
-
 		// Button bindings.
 		$('#save').click( function( event ) {
 			previewer.save();
Index: wp-admin/css/wp-admin-rtl.css
===================================================================
--- wp-admin/css/wp-admin-rtl.css	(revision 23401)
+++ wp-admin/css/wp-admin-rtl.css	(working copy)
@@ -2534,6 +2534,15 @@
 	direction: ltr;
 }
 
+.control-section .accordion-section-title {
+	font-family: Tahoma, Arial, sans-serif;
+}
+
+.accordion-section-title:after {
+	right: auto;
+	left: 20px;
+}
+
 /**
  * HiDPI Displays
  */
Index: wp-admin/css/wp-admin.css
===================================================================
--- wp-admin/css/wp-admin.css	(revision 23401)
+++ wp-admin/css/wp-admin.css	(working copy)
@@ -8347,6 +8347,121 @@
 	-ms-touch-action: none;
 }
 
+/* Accordion */
+
+.accordion-section {
+	border-top: 1px solid #fff;
+	border-bottom: 1px solid #dfdfdf;
+	margin: 0;
+}
+
+.accordion-section:last-child {
+	box-shadow: 0 1px 0 0px #fff;
+}
+
+.accordion-section.open .accordion-section-content {
+	display: block;
+	background: #fdfdfd;
+}
+
+.accordion-section.open:hover {
+	border-bottom-color: #dfdfdf;
+}
+
+.accordion-section-content {
+	display: none;
+	padding: 10px 20px 15px;
+	overflow: hidden;
+}
+
+.accordion-section-title {
+	margin: 0;
+	padding: 15px 20px;
+	position: relative;
+
+	cursor: pointer;
+
+	-webkit-user-select: none;
+	-moz-user-select: none;
+	user-select: none;
+}
+
+.accordion-section-title:after {
+	content: '';
+	width: 0;
+	height: 0;
+	border-color: #ccc transparent;
+	border-style: solid;
+	border-width: 6px 6px 0;
+	position: absolute;
+	top: 25px;
+	right: 20px;
+	z-index: 1;
+}
+
+.accordion-section-title:focus {
+	outline: none;
+}
+
+.accordion-section-title:hover:after,
+.accordion-section-title:focus:after {
+	border-color: #aaa transparent;
+}
+
+.cannot-expand .accordion-section-title {
+	cursor: auto;
+}
+
+.cannot-expand .accordion-section-title:after {
+	display: none;
+}
+
+.control-section .accordion-section-title {
+	padding: 10px 20px;
+	font-size: 15px;
+	font-family: Georgia, "Times New Roman", "Bitstream Charter", Times, serif;
+	font-weight: normal;
+	text-shadow: 0 1px 0 #fff;
+	background: #f5f5f5;
+	background-image: -webkit-gradient(linear, left bottom, left top, from(#eee), to(#f5f5f5));
+	background-image: -webkit-linear-gradient(bottom, #eee, #f5f5f5);
+	background-image:    -moz-linear-gradient(bottom, #eee, #f5f5f5);
+	background-image:      -o-linear-gradient(bottom, #eee, #f5f5f5);
+	background-image: linear-gradient(to top, #eee, #f5f5f5);
+}
+
+.control-section .accordion-section-title:after {
+	top: 15px;
+}
+
+.control-section .accordion-section-title:hover:after,
+.control-section .accordion-section-title:focus:after {
+	border-color: #eee transparent;
+}
+
+.control-section:hover .accordion-section-title,
+.control-section .accordion-section-title:hover,
+.control-section.open .accordion-section-title,
+.control-section .accordion-section-title:focus {
+	color: #fff;
+	text-shadow: 0 -1px 0 #333;
+	background: #808080;
+	background-image: -webkit-gradient(linear, left bottom, left top, from(#6d6d6d), to(#808080));
+	background-image: -webkit-linear-gradient(bottom, #6d6d6d, #808080);
+	background-image:    -moz-linear-gradient(bottom, #6d6d6d, #808080);
+	background-image:      -o-linear-gradient(bottom, #6d6d6d, #808080);
+	background-image: linear-gradient(to top, #6d6d6d, #808080);
+}
+
+.control-section.accordion-section:hover,
+.control-section.accordion-section.open {
+	border-top-color: #808080;
+}
+
+.control-section.open .accordion-section-title {
+	border-bottom: 1px solid #6d6d6d;
+}
+
 /* =Media Queries
 -------------------------------------------------------------- */
 
Index: wp-admin/css/customize-controls-rtl.css
===================================================================
--- wp-admin/css/customize-controls-rtl.css	(revision 23401)
+++ wp-admin/css/customize-controls-rtl.css	(working copy)
@@ -1,11 +1,3 @@
-.control-section .customize-section-title {
-	font-family: Tahoma, Arial, sans-serif;
-}
-.customize-section-title:after {
-	right: auto;
-	left: 20px;
-}
-
 #customize-header-actions .button-primary {
 	float: left;
 }
Index: wp-admin/css/customize-controls.css
===================================================================
--- wp-admin/css/customize-controls.css	(revision 23401)
+++ wp-admin/css/customize-controls.css	(working copy)
@@ -6,124 +6,7 @@
 	text-decoration: none;
 }
 
-.customize-section {
-	border-top: 1px solid #fff;
-	border-bottom: 1px solid #dfdfdf;
-	margin: 0;
-}
-
-.control-section.customize-section:hover,
-.control-section.customize-section.open {
-	border-top-color: #808080;
-}
-
-.control-section.customize-section:hover {
-	border-bottom-color: #6d6d6d;
-}
-
-.customize-section.open:hover {
-	border-bottom-color: #dfdfdf;
-}
-
-.customize-section:last-child {
-	box-shadow: 0 1px 0 0px #fff;
-}
-
-.customize-section-title {
-	margin: 0;
-	padding: 15px 20px;
-	position: relative;
-
-	cursor: pointer;
-
-	-webkit-user-select: none;
-	-moz-user-select: none;
-	user-select: none;
-}
-
-.customize-section-title:focus {
-	outline: none;
-}
-
-.cannot-expand .customize-section-title {
-	cursor: auto;
-}
-
-.customize-section-content {
-	display: none;
-	padding: 10px 20px 15px;
-	overflow: hidden;
-}
-
-.control-section .customize-section-title {
-	padding: 10px 20px;
-	font-size: 15px;
-	font-family: Georgia, "Times New Roman", "Bitstream Charter", Times, serif;
-	font-weight: normal;
-	text-shadow: 0 1px 0 #fff;
-	background: #f5f5f5;
-	background-image: -webkit-gradient(linear, left bottom, left top, from(#eee), to(#f5f5f5));
-	background-image: -webkit-linear-gradient(bottom, #eee, #f5f5f5);
-	background-image:    -moz-linear-gradient(bottom, #eee, #f5f5f5);
-	background-image:      -o-linear-gradient(bottom, #eee, #f5f5f5);
-	background-image: linear-gradient(to top, #eee, #f5f5f5);
-}
-
-.control-section:hover .customize-section-title,
-.control-section .customize-section-title:hover,
-.control-section.open .customize-section-title,
-.control-section .customize-section-title:focus {
-	color: #fff;
-	text-shadow: 0 -1px 0 #333;
-	background: #808080;
-	background-image: -webkit-gradient(linear, left bottom, left top, from(#6d6d6d), to(#808080));
-	background-image: -webkit-linear-gradient(bottom, #6d6d6d, #808080);
-	background-image:    -moz-linear-gradient(bottom, #6d6d6d, #808080);
-	background-image:      -o-linear-gradient(bottom, #6d6d6d, #808080);
-	background-image: linear-gradient(to top, #6d6d6d, #808080);
-}
-
-.control-section.open .customize-section-title {
-	border-bottom: 1px solid #6d6d6d;
-}
-
-.customize-section.open .customize-section-content {
-	display: block;
-	background: #fdfdfd;
-}
-
-.customize-section-title:after {
-	content: '';
-	width: 0;
-	height: 0;
-	border-color: #ccc transparent;
-	border-style: solid;
-	border-width: 6px 6px 0;
-	position: absolute;
-	top: 25px;
-	right: 20px;
-	z-index: 1;
-}
-
-.cannot-expand .customize-section-title:after {
-	display: none;
-}
-
-.customize-section-title:hover:after,
-.customize-section-title:focus:after {
-	border-color: #aaa transparent;
-}
-
-.control-section .customize-section-title:hover:after,
-.control-section .customize-section-title:focus:after {
-	border-color: #eee transparent;
-}
-
-.control-section .customize-section-title:after {
-	top: 15px;
-}
-
-#customize-info .customize-section-content {
+#customize-info .accordion-section-content {
 	background: transparent;
 }
 
@@ -158,7 +41,7 @@
 }
 
 #customize-theme-controls > ul,
-#customize-theme-controls .customize-section-content {
+#customize-theme-controls .accordion-section-content {
 	margin: 0;
 }
 
@@ -245,7 +128,7 @@
 /*
  * Dropdowns
  */
-.customize-section .dropdown {
+.accordion-section .dropdown {
 	float: left;
 	display: block;
 	position: relative;
@@ -255,7 +138,7 @@
 	border-radius: 3px;
 }
 
-.customize-section .dropdown-content {
+.accordion-section .dropdown-content {
 	overflow: hidden;
 	float: left;
 	min-width: 30px;
@@ -301,12 +184,12 @@
 	z-index: 1;
 }
 
-.customize-section .dropdown:hover .dropdown-content,
+.accordion-section .dropdown:hover .dropdown-content,
 .customize-control .dropdown:hover .dropdown-arrow {
 	border-color: #aaa;
 }
 
-.customize-section .dropdown:hover .dropdown-arrow:after {
+.accordion-section .dropdown:hover .dropdown-arrow:after {
 	border-color: #aaa transparent;
 }
 
@@ -341,7 +224,7 @@
 	border-color: rgba( 0, 0, 0, 0.25 );
 }
 
-.customize-section input[type="text"].color-picker-hex {
+.accordion-section input[type="text"].color-picker-hex {
 	width: 65px;
 	font-family: monospace;
 	text-align: center;
@@ -349,10 +232,10 @@
 }
 
 /* The centered cursor overlaps the placeholder in webkit. Hide it when selected. */
-.customize-section input[type="text"].color-picker-hex:focus::-webkit-input-placeholder {
+.accordion-section input[type="text"].color-picker-hex:focus::-webkit-input-placeholder {
 	color: transparent;
 }
-.customize-section input[type="text"].color-picker-hex:-moz-placeholder {
+.accordion-section input[type="text"].color-picker-hex:-moz-placeholder {
 	color: #999;
 }
 
@@ -371,18 +254,18 @@
 	display: block;
 }
 
-.customize-section .customize-control-image .dropdown-content {
+.accordion-section .customize-control-image .dropdown-content {
 	height: auto;
 	min-height: 24px;
 	min-width: 40px;
 	padding: 0;
 }
 
-.customize-section .customize-control-image .dropdown-status {
+.accordion-section .customize-control-image .dropdown-status {
 	padding: 4px 5px;
 }
 
-.customize-section .customize-control-image .preview-thumbnail img {
+.accordion-section .customize-control-image .preview-thumbnail img {
 	display: block;
 	width: 100%;
 	max-width: 122px;
@@ -390,18 +273,18 @@
 	margin: 0 auto;
 }
 
-.customize-section .customize-control-image .actions {
+.accordion-section .customize-control-image .actions {
 	text-align: right;
 }
 
-.customize-section .customize-control-image .library ul {
+.accordion-section .customize-control-image .library ul {
 	border-bottom: 1px solid #dfdfdf;
 	float: left;
 	width: 100%;
 	margin: 10px 0 0;
 }
 
-.customize-section .customize-control-image .library li {
+.accordion-section .customize-control-image .library li {
 	color: #999;
 	float: left;
 	padding: 3px 5px;
@@ -411,7 +294,7 @@
 	border-width: 1px 1px 0 1px;
 }
 
-.customize-section .customize-control-image .library li.library-selected {
+.accordion-section .customize-control-image .library li.library-selected {
 	margin-bottom: -1px;
 	padding-bottom: 4px;
 
@@ -422,27 +305,27 @@
 	border-radius: 3px 3px 0 0 ;
 }
 
-.customize-section .customize-control-image .library-content {
+.accordion-section .customize-control-image .library-content {
 	display: none;
 	width: 100%;
 	float: left;
 	padding: 10px 0;
 }
 
-.customize-section .customize-control-image .library-content.library-selected {
+.accordion-section .customize-control-image .library-content.library-selected {
 	display: block;
 }
 
-.customize-section .customize-control-image .library .thumbnail {
+.accordion-section .customize-control-image .library .thumbnail {
 	display: block;
 	width: 100%;
 }
 
-.customize-section .customize-control-image .library .thumbnail:hover img {
+.accordion-section .customize-control-image .library .thumbnail:hover img {
 	border-color: #21759b;
 }
 
-.customize-section .customize-control-image .library .thumbnail img {
+.accordion-section .customize-control-image .library .thumbnail img {
 	display: block;
 	max-width: 90%;
 	max-height: 80px;
@@ -453,13 +336,13 @@
 	border: 1px solid #dfdfdf;
 }
 
-.customize-section .customize-control-upload .upload-fallback,
-.customize-section .customize-control-image .upload-fallback {
+.accordion-section .customize-control-upload .upload-fallback,
+.accordion-section .customize-control-image .upload-fallback {
 	display: none;
 }
 
-.customize-section .customize-control-upload .upload-dropzone,
-.customize-section .customize-control-image .upload-dropzone {
+.accordion-section .customize-control-upload .upload-dropzone,
+.accordion-section .customize-control-image .upload-dropzone {
 	display: none;
 	padding: 15px 10px;
 	border: 3px dashed #dfdfdf;
@@ -470,8 +353,8 @@
 	cursor: default;
 }
 
-.customize-section .customize-control-upload .upload-dropzone.supports-drag-drop,
-.customize-section .customize-control-image .upload-dropzone.supports-drag-drop {
+.accordion-section .customize-control-upload .upload-dropzone.supports-drag-drop,
+.accordion-section .customize-control-image .upload-dropzone.supports-drag-drop {
 	display: block;
 	-webkit-transition: border-color 0.1s;
 	-moz-transition:    border-color 0.1s;
@@ -480,13 +363,13 @@
 	transition:         border-color 0.1s;
 }
 
-.customize-section .customize-control-upload .library ul li,
-.customize-section .customize-control-image .library ul li {
+.accordion-section .customize-control-upload .library ul li,
+.accordion-section .customize-control-image .library ul li {
 	cursor: pointer;
 }
 
-.customize-section .customize-control-upload .upload-dropzone.supports-drag-drop.drag-over,
-.customize-section .customize-control-image .upload-dropzone.supports-drag-drop.drag-over {
+.accordion-section .customize-control-upload .upload-dropzone.supports-drag-drop.drag-over,
+.accordion-section .customize-control-image .upload-dropzone.supports-drag-drop.drag-over {
 	border-color: #83b4d8;
 }