diff --git a/assets/src/stories-editor/components/inserter/edit.css b/assets/src/stories-editor/components/inserter/edit.css
new file mode 100644
index 00000000000..9882bad618c
--- /dev/null
+++ b/assets/src/stories-editor/components/inserter/edit.css
@@ -0,0 +1,3 @@
+.amp__block-editor-inserter__menu.block-editor-inserter__menu {
+	flex-direction: column;
+}
diff --git a/assets/src/stories-editor/components/inserter/index.js b/assets/src/stories-editor/components/inserter/index.js
index 31cff1407eb..9f651f8416f 100644
--- a/assets/src/stories-editor/components/inserter/index.js
+++ b/assets/src/stories-editor/components/inserter/index.js
@@ -25,6 +25,7 @@ import { withSelect } from '@wordpress/data';
  * Internal dependencies
  */
 import InserterMenu from './menu'; // eslint-disable-line import/no-named-as-default
+import './edit.css';
 
 const defaultRenderToggle = ( { onToggle, disabled, isOpen } ) => (
 	<IconButton
diff --git a/assets/src/stories-editor/components/inserter/menu.js b/assets/src/stories-editor/components/inserter/menu.js
index e4c8a40279a..677b60b8c94 100644
--- a/assets/src/stories-editor/components/inserter/menu.js
+++ b/assets/src/stories-editor/components/inserter/menu.js
@@ -274,7 +274,7 @@ export class InserterMenu extends Component {
 		/* eslint-disable jsx-a11y/no-autofocus, jsx-a11y/no-static-element-interactions */
 		return (
 			<div
-				className="editor-inserter__menu block-editor-inserter__menu"
+				className="editor-inserter__menu block-editor-inserter__menu amp__block-editor-inserter__menu"
 				onKeyPress={ stopKeyPropagation }
 				onKeyDown={ this.onKeyDown }
 			>
@@ -285,13 +285,13 @@ export class InserterMenu extends Component {
 					id={ `block-editor-inserter__search-${ instanceId }` }
 					type="search"
 					placeholder={ __( 'Search for an element', 'amp' ) }
-					className="editor-inserter__search block-editor-inserter__search"
+					className="editor-inserter__search block-editor-inserter__search amp__block-editor-inserter__search"
 					autoFocus
 					onChange={ this.onChangeSearchInput }
 				/>
 
 				<div
-					className="editor-inserter__results block-editor-inserter__results"
+					className="editor-inserter__results amp__block-editor-inserter__results block-editor-inserter__results"
 					ref={ this.inserterResults }
 					tabIndex="0"
 					role="region"