diff --git src/wp-admin/css/customize-controls.css src/wp-admin/css/customize-controls.css
index 8c5cc10..23806c4 100644
--- src/wp-admin/css/customize-controls.css
+++ src/wp-admin/css/customize-controls.css
@@ -2020,10 +2020,6 @@ p.customize-section-description {
 	display: none; /* Hide "installed" notice on installed themes tab. */
 }
 
-.control-panel-themes .theme-browser .theme .theme-actions .button-primary {
-	margin: 0 0 0 8px;
-}
-
 .customize-control-theme .theme {
 	width: 100%;
 	margin: 0;
@@ -2094,6 +2090,19 @@ p.customize-section-description {
 	font-size: 15px;
 }
 
+.theme-id-container {
+	position: relative;
+}
+
+.theme-browser .theme.active .theme-actions,
+.wp-customizer .theme-browser .theme .theme-actions {
+	position: absolute;
+	top: 50%;
+	transform: translateY(-50%);
+	right: 0;
+	padding: 0 15px;
+}
+
 #customize-controls .theme-overlay .theme-name {
 	font-size: 32px;
 }
@@ -2118,13 +2127,15 @@ p.customize-section-description {
 
 .themes-filter-bar .wp-filter-search {
 	line-height: 25px;
-	padding: 3px 5px;
+	padding: 6px 10px 6px 30px;
 	max-width: 100%;
 	width: 40%;
 	min-width: 300px;
 	position: absolute;
 	top: 6px;
 	left: 25px;
+	height: 32px;
+	margin: 1px 0;
 }
 
 /* Unstick the filter bar on short windows/screens. This breakpoint is based on the
@@ -2233,7 +2244,7 @@ p.customize-section-description {
 	.wp-customizer .showing-themes .control-panel-themes .customize-themes-mobile-back:before {
 		left: 0;
 		top: 0;
-		height: 42px;
+		height: 46px;
 		width: 26px;
 		display: block;
 		line-height: 46px;
@@ -2253,6 +2264,10 @@ p.customize-section-description {
 	.showing-themes #customize-header-actions {
 		display: none;
 	}
+
+	#customize-controls {
+		width: 100%;
+	}
 }
 
 /* Details View */
@@ -2363,6 +2378,10 @@ p.customize-section-description {
 		top: 0;
 		bottom: 0;
 	}
+
+	.wp-customizer .theme-browser .themes {
+		padding-right: 25px;
+	}
 }
 
 /* Handle cheaters. */
@@ -2677,7 +2696,7 @@ body.adding-widget .add-new-widget:before,
 }
 
 #available-menu-items-search .search-icon:after,
-#available-widgets-filter .search-icon:after {
+.themes-filter-bar .search-icon:after {
 	content: "\f179";
 	font: normal 20px/1 dashicons;
 	vertical-align: middle;
@@ -2685,6 +2704,18 @@ body.adding-widget .add-new-widget:before,
 	-moz-osx-font-smoothing: grayscale;
 }
 
+.themes-filter-bar .search-icon {
+	position: absolute;
+	top: 7px;
+	left: 26px;
+	z-index: 1;
+	color: #72777c;
+	height: 30px;
+	width: 30px;
+	line-height: 2;
+	text-align: center;
+}
+
 .no-widgets-found-message {
 	display: none;
 	margin: 0;
@@ -2797,6 +2828,10 @@ body.adding-widget .add-new-widget:before,
 	.media-widget-control .media-widget-buttons .button.select-media {
 		margin-top: 12px;
 	}
+
+	.wp-core-ui .themes-filter-bar .feature-filter-toggle {
+		margin: 3px 0 3px 25px;
+	}
 }
 
 @media screen and ( max-width: 1200px ) {
@@ -2808,9 +2843,6 @@ body.adding-widget .add-new-widget:before,
 }
 
 @media screen and ( max-width: 640px ) {
-	#customize-controls {
-		width: 100%;
-	}
 
 	.wp-full-overlay.expanded,
 	.outer-section-open .wp-full-overlay.expanded {
@@ -2846,7 +2878,7 @@ body.adding-widget .add-new-widget:before,
 	}
 
 	#customize-footer-actions,
-	#customize-preview,
+	/*#customize-preview,*/
 	.customize-controls-preview-toggle .controls,
 	.preview-only .wp-full-overlay-sidebar-content,
 	.preview-only .customize-controls-preview-toggle .preview {
@@ -2879,10 +2911,8 @@ body.adding-widget .add-new-widget:before,
 		display: block;
 	}
 
-	#customize-preview {
-		top: 45px;
-		bottom: 0;
-		height: auto;
+	.wp-full-overlay.expanded {
+		margin-left: 300px;
 	}
 
 	.wp-core-ui.wp-customizer .button {
@@ -2891,8 +2921,6 @@ body.adding-widget .add-new-widget:before,
 		font-size: 14px;
 		vertical-align: middle;
 		height: auto;
-		margin-bottom: 4px;
-		margin-top: 12px;
 	}
 
 	#publish-settings {
@@ -2974,4 +3002,8 @@ body.adding-widget .add-new-widget:before,
 	.reordering .reorder-done {
 		padding: 8px;
 	}
+
+	.wp-core-ui .themes-filter-bar .feature-filter-toggle {
+		margin: 0;
+	}
 }
diff --git src/wp-admin/css/themes.css src/wp-admin/css/themes.css
index e339448..c6f7972 100644
--- src/wp-admin/css/themes.css
+++ src/wp-admin/css/themes.css
@@ -97,11 +97,7 @@ body.js .theme-browser.search-loading {
 	-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
 	opacity: 0;
 	transition: opacity 0.1s ease-in-out;
-	position: absolute;
-	bottom: 0;
-	right: 0;
-	height: 38px;
-	padding: 9px 10px 0 10px;
+	height: auto;
 	background: rgba(244, 244, 244, 0.7);
 	border-left: 1px solid rgba(0,0,0,0.05);
 }
diff --git src/wp-includes/customize/class-wp-customize-theme-control.php src/wp-includes/customize/class-wp-customize-theme-control.php
index 886a711..1491430 100644
--- src/wp-includes/customize/class-wp-customize-theme-control.php
+++ src/wp-includes/customize/class-wp-customize-theme-control.php
@@ -99,27 +99,33 @@ class WP_Customize_Theme_Control extends WP_Customize_Control {
 			<# } #>
 
 			<# if ( data.theme.active ) { #>
-				<h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">
-					<?php
-					/* translators: %s: theme name */
-					printf( __( '<span>Previewing:</span> %s' ), '{{ data.theme.name }}' );
-					?>
-				</h3>
-				<div class="theme-actions">
-					<button type="button" class="button button-primary customize-theme" aria-label="<?php echo esc_attr( $customize_label ); ?>"><?php _e( 'Customize' ); ?></button>
-				</div>
+                <div class="theme-id-container">
+                    <h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">
+                        <?php
+                        /* translators: %s: theme name */
+                        printf( __( '<span>Previewing:</span> %s' ), '{{ data.theme.name }}' );
+                        ?>
+                    </h3>
+                    <div class="theme-actions">
+                        <button type="button" class="button button-primary customize-theme" aria-label="<?php echo esc_attr( $customize_label ); ?>"><?php _e( 'Customize' ); ?></button>
+                    </div>
+                </div>
 				<div class="notice notice-success notice-alt"><p><?php _e( 'Installed' ); ?></p></div>
 			<# } else if ( 'installed' === data.theme.type ) { #>
-				<h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">{{ data.theme.name }}</h3>
-				<div class="theme-actions">
-					<button type="button" class="button button-primary preview-theme" aria-label="<?php echo esc_attr( $preview_label ); ?>" data-slug="{{ data.theme.id }}"><?php _e( 'Live Preview' ); ?></span>
-				</div>
+                <div class="theme-id-container">
+                    <h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">{{ data.theme.name }}</h3>
+                    <div class="theme-actions">
+                        <button type="button" class="button button-primary preview-theme" aria-label="<?php echo esc_attr( $preview_label ); ?>" data-slug="{{ data.theme.id }}"><?php _e( 'Live Preview' ); ?></span>
+                    </div>
+                </div>
 				<div class="notice notice-success notice-alt"><p><?php _e( 'Installed' ); ?></p></div>
 			<# } else { #>
-				<h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">{{ data.theme.name }}</h3>
-				<div class="theme-actions">
-					<button type="button" class="button button-primary theme-install preview" aria-label="<?php echo esc_attr( $install_label ); ?>" data-slug="{{ data.theme.id }}" data-name="{{ data.theme.name }}"><?php _e( 'Install &amp; Preview' ); ?></button>
-				</div>
+                <div class="theme-id-container">
+                    <h3 class="theme-name" id="{{ data.section }}-{{ data.theme.id }}-name">{{ data.theme.name }}</h3>
+                    <div class="theme-actions">
+                        <button type="button" class="button button-primary theme-install preview" aria-label="<?php echo esc_attr( $install_label ); ?>" data-slug="{{ data.theme.id }}" data-name="{{ data.theme.name }}"><?php _e( 'Install &amp; Preview' ); ?></button>
+                    </div>
+                </div>
 			<# } #>
 		</div>
 	<?php
diff --git src/wp-includes/customize/class-wp-customize-themes-section.php src/wp-includes/customize/class-wp-customize-themes-section.php
index a89439a..032c53a 100644
--- src/wp-includes/customize/class-wp-customize-themes-section.php
+++ src/wp-includes/customize/class-wp-customize-themes-section.php
@@ -114,7 +114,8 @@ class WP_Customize_Themes_Section extends WP_Customize_Section {
 			<div class="search-form">
 				<label for="wp-filter-search-input-{{ data.id }}" class="screen-reader-text"><?php _e( 'Search themes&hellip;' ); ?></label>
 				<input type="search" id="wp-filter-search-input-{{ data.id }}" placeholder="<?php esc_attr_e( 'Search themes&hellip;' ); ?>" aria-describedby="{{ data.id }}-live-search-desc" class="wp-filter-search">
-				<span id="{{ data.id }}-live-search-desc" class="screen-reader-text"><?php _e( 'The search results will be updated as you type.' ); ?></span>
+                <div class="search-icon" aria-hidden="true"></div>
+                <span id="{{ data.id }}-live-search-desc" class="screen-reader-text"><?php _e( 'The search results will be updated as you type.' ); ?></span>
 			</div>
 			<button type="button" class="button feature-filter-toggle">
 				<span class="filter-count-0"><?php _e( 'Filter themes' ); ?></span><span class="filter-count-filters">
@@ -144,7 +145,8 @@ class WP_Customize_Themes_Section extends WP_Customize_Section {
 			<div class="themes-filter-container">
 				<label for="{{ data.id }}-themes-filter" class="screen-reader-text"><?php _e( 'Search themes&hellip;' ); ?></label>
 				<input type="search" id="{{ data.id }}-themes-filter" placeholder="<?php esc_attr_e( 'Search themes&hellip;' ); ?>" aria-describedby="{{ data.id }}-live-search-desc" class="wp-filter-search wp-filter-search-themes" />
-				<span id="{{ data.id }}-live-search-desc" class="screen-reader-text"><?php _e( 'The search results will be updated as you type.' ); ?></span>
+                <div class="search-icon" aria-hidden="true"></div>
+                <span id="{{ data.id }}-live-search-desc" class="screen-reader-text"><?php _e( 'The search results will be updated as you type.' ); ?></span>
 			</div>
 		<# } #>
 		<div class="filter-themes-count">