diff --git a/app/components/cards/CardStack/CardStack.container.tsx b/app/components/cards/CardStack/CardStack.container.tsx
index 50e251d..a7e5782 100644
--- a/app/components/cards/CardStack/CardStack.container.tsx
+++ b/app/components/cards/CardStack/CardStack.container.tsx
@@ -11,6 +11,8 @@ const DEFAULT_TOGGLE_LABEL = "See all communication approaches";
  * Figma: "Utility / CardStack"; canonical code under `cards/`.
  * Selectable stack of cards with
  * an optional "see all"/"show less" expand toggle.
+ * Expanded default layout matches Flow — Expanded Card Stack (`20768:14820`):
+ * 281×142 CardSelection tiles in two columns.
  */
 const CardStackContainer = memo<CardStackProps>(
   ({
diff --git a/app/components/cards/CardStack/CardStack.types.ts b/app/components/cards/CardStack/CardStack.types.ts
index 00b7776..2fc4b8d 100644
--- a/app/components/cards/CardStack/CardStack.types.ts
+++ b/app/components/cards/CardStack/CardStack.types.ts
@@ -20,7 +20,7 @@ export interface CardStackProps {
   showLessLabel?: string;
   title?: string;
   description?: ReactNode;
-  /** "default" = compact grid/column + expanded grid; "singleStack" = always one column, expand shows more in same stack */
+  /** "default" = compact grid/column + expanded 2-col 142px tiles; "singleStack" = always one column, expand shows more in same stack */
   layout?: "default" | "singleStack";
   /**
    * Max recommended cards in compact (non-expanded) mode. Default 5; Figma compact stack uses 3.
diff --git a/app/components/cards/CardStack/CardStack.view.tsx b/app/components/cards/CardStack/CardStack.view.tsx
index 2f7f6b8..485dd38 100644
--- a/app/components/cards/CardStack/CardStack.view.tsx
+++ b/app/components/cards/CardStack/CardStack.view.tsx
@@ -6,6 +6,10 @@ import type { HeaderLockupSizeValue } from "../../type/HeaderLockup/HeaderLockup
 import Selection from "../Selection";
 import type { CardStackViewProps } from "./CardStack.types";
 
+/** Figma Card / CardSelection on Compact + Expanded Card Stack (`281×142`). */
+const FIGMA_CARD_SELECTION_TILE_CLASS =
+  "h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0";
+
 function CardStackHeaderLockup({
   title,
   description,
@@ -175,24 +179,46 @@ export function CardStackView({
       />
 
       {expanded ? (
-        <div className="mx-auto grid w-full max-w-[min(100%,860px)] grid-cols-1 gap-x-4 gap-y-6 md:grid-cols-2">
-          {cards.map((item) => (
-            <Selection
-              key={item.id}
-              id={item.id}
-              label={item.label}
-              supportText={item.supportText}
-              recommended={item.recommended ?? false}
-              selected={isSelected(item.id)}
-              orientation="vertical"
-              showInfoIcon={true}
-              onClick={() => onCardSelect(item.id)}
-            />
-          ))}
-          {addTile ? (
-            <div className="min-w-0 md:col-span-2">{addTile}</div>
-          ) : null}
-        </div>
+        <>
+          <div className="flex w-full flex-col gap-2 md:hidden">
+            {cards.map((item) => (
+              <Selection
+                key={item.id}
+                id={item.id}
+                label={item.label}
+                supportText={item.supportText}
+                recommended={item.recommended ?? false}
+                selected={isSelected(item.id)}
+                orientation="horizontal"
+                showInfoIcon={false}
+                className="min-h-[142px]"
+                onClick={() => onCardSelect(item.id)}
+              />
+            ))}
+            {addTile}
+          </div>
+          <div className="mx-auto hidden w-full max-w-[min(100%,570px)] flex-wrap justify-center gap-2 md:flex">
+            {cards.map((item) => (
+              <Selection
+                key={item.id}
+                id={item.id}
+                label={item.label}
+                supportText={item.supportText}
+                recommended={item.recommended ?? false}
+                selected={isSelected(item.id)}
+                orientation="horizontal"
+                showInfoIcon={false}
+                className={FIGMA_CARD_SELECTION_TILE_CLASS}
+                onClick={() => onCardSelect(item.id)}
+              />
+            ))}
+            {addTile ? (
+              <div className="flex w-full min-w-0 shrink-0 justify-center md:flex-[1_1_100%]">
+                {addTile}
+              </div>
+            ) : null}
+          </div>
+        </>
       ) : compactDesktopLayout === "pyramidFive" ? (
         <>
           <div className="flex w-full flex-col gap-2 md:hidden">
@@ -230,7 +256,7 @@ export function CardStackView({
                     selected={isSelected(item.id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(item.id)}
                   />
                 ))}
@@ -249,7 +275,7 @@ export function CardStackView({
                         selected={isSelected(item.id)}
                         orientation="horizontal"
                         showInfoIcon={false}
-                        className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                        className={FIGMA_CARD_SELECTION_TILE_CLASS}
                         onClick={() => onCardSelect(item.id)}
                       />
                     ))}
@@ -268,7 +294,7 @@ export function CardStackView({
                     selected={isSelected(item.id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(item.id)}
                   />
                 ))}
@@ -284,7 +310,7 @@ export function CardStackView({
                     selected={isSelected(item.id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(item.id)}
                   />
                 ))}
@@ -299,7 +325,7 @@ export function CardStackView({
                     selected={isSelected(compactCards[4].id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(compactCards[4].id)}
                   />
                 </div>
@@ -346,7 +372,7 @@ export function CardStackView({
                       selected={isSelected(item.id)}
                       orientation="horizontal"
                       showInfoIcon={false}
-                      className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                      className={FIGMA_CARD_SELECTION_TILE_CLASS}
                       onClick={() => onCardSelect(item.id)}
                     />
                   ))}
@@ -360,7 +386,7 @@ export function CardStackView({
                     selected={isSelected(compactCards[2].id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(compactCards[2].id)}
                   />
                 </div>
@@ -379,7 +405,7 @@ export function CardStackView({
                     selected={isSelected(item.id)}
                     orientation="horizontal"
                     showInfoIcon={false}
-                    className="h-[142px] min-h-[142px] max-h-[142px] w-[281px] max-w-[281px] shrink-0"
+                    className={FIGMA_CARD_SELECTION_TILE_CLASS}
                     onClick={() => onCardSelect(item.id)}
                   />
                 ))}
diff --git a/app/components/cards/Selection/Selection.container.tsx b/app/components/cards/Selection/Selection.container.tsx
index 10a2d7f..1825343 100644
--- a/app/components/cards/Selection/Selection.container.tsx
+++ b/app/components/cards/Selection/Selection.container.tsx
@@ -6,7 +6,7 @@ import type { SelectionProps } from "./Selection.types";
 
 /**
  * Figma: "Card / CardSelection" — stacked tile e.g. `16775:28762` (recommended + label + supportText).
- * `orientation="horizontal"` selects that vertical stack; `"vertical"` is label + optional info icon with tag on the right (CardStack expanded / single-column).
+ * `orientation="horizontal"` selects that vertical stack; `"vertical"` is label + optional info icon with tag on the right (CardStack `singleStack` / right-rail).
  */
 const SelectionContainer = memo<SelectionProps>(
   ({
diff --git a/stories/cards/CardStack.stories.js b/stories/cards/CardStack.stories.js
index 545d0be..2259f8f 100644
--- a/stories/cards/CardStack.stories.js
+++ b/stories/cards/CardStack.stories.js
@@ -97,7 +97,8 @@ export const Expanded = {
   parameters: {
     docs: {
       description: {
-        story: "Expanded list layout with vertical cards and Show less toggle.",
+        story:
+          "Expanded 2-column stack of 142px CardSelection tiles and Show less toggle.",
       },
     },
   },
diff --git a/tests/unit/CardStack.test.jsx b/tests/unit/CardStack.test.jsx
index e09253a..4470b72 100644
--- a/tests/unit/CardStack.test.jsx
+++ b/tests/unit/CardStack.test.jsx
@@ -60,9 +60,23 @@ describe("CardStack Component", () => {
   test("renders all cards in expanded (list) mode", () => {
     render(<CardStack cards={SAMPLE_CARDS} expanded={true} />);
 
-    expect(screen.getByText("Option A")).toBeInTheDocument();
-    expect(screen.getByText("Option B")).toBeInTheDocument();
-    expect(screen.getByText("Option C")).toBeInTheDocument();
+    expect(screen.getAllByText("Option A").length).toBeGreaterThanOrEqual(1);
+    expect(screen.getAllByText("Option B").length).toBeGreaterThanOrEqual(1);
+    expect(screen.getAllByText("Option C").length).toBeGreaterThanOrEqual(1);
+  });
+
+  test("expanded tiles use the compact 142px CardSelection height", () => {
+    render(<CardStack cards={SAMPLE_CARDS} expanded={true} />);
+
+    const tiles = screen.getAllByRole("button", {
+      name: "Option A: Description A",
+    });
+    expect(tiles.length).toBeGreaterThan(0);
+    for (const tile of tiles) {
+      expect(tile.className).toMatch(/142px/);
+      expect(tile).toHaveClass("flex-col");
+      expect(tile).not.toHaveClass("flex-row");
+    }
   });
 
   test("shows See all toggle when hasMore is true", () => {