diff --git a/README.md b/README.md
index 55d17c5..13c55e4 100644
--- a/README.md
+++ b/README.md
@@ -367,6 +367,7 @@ npm run preview
 - Effect idea moderation uses `EFFECT_MODERATION_TOKEN` (falls back to `DOODLE_MODERATION_TOKEN` / `DOODLE_ADMIN_TOKEN`). Each submission now gets a signed review page at `/effect-review.html?id=...&token=...` with live preview + submitted code, approve/reject links still use `/api/effects?action=approve|reject&id=...&token=...`, and pending queue inspection stays at `/api/effects?includePending=1&token=...`.
 - Run `npm run test:integration` in an environment with the DB2 secrets set to verify the live Upstash database exists and can be read/written. If the DB2 URL is malformed, the APIs now fail closed instead of crashing with a 500 during Redis client creation. The serverless API modules also use explicit `.js` ESM imports so Vercel can resolve the emitted files correctly.
 - Append `?editor=1` in dev builds to open the Scene + Timeline Editor (or toggle "Editor mode" in the debug overlay). The editor shows a live preview, edits hot-apply to the running demo, and changes persist to localStorage.
+- Mobile-first editing mode: choose **Editor layout → Mobile** in the debug overlay (or use `?editor=1&editorLayout=mobile`) to switch to a stacked touch-friendly layout while keeping the existing desktop editor intact.
 - The timeline editor layout uses a narrow Scenes sidebar, a center workspace with Preview plus a single accordion stack for Basic/Main Slots/Transition, and a right Inspector for scene/layer/cue editing. The Generate Text Cues tool opens from a bottom-left button as a modal.
 - The timeline area now dedicates at least half the editor height, renders all scenes on the main track, and adds extra rows for selected-scene layers and scene automation entries.
 - Automation clip editing foundations now treat automation as point-driven envelopes (per-segment curve type + tension metadata), with helpers for snapped point add/remove/move, slide-mode temporal shifting, and segment-level curve/tension updates for timeline UI integration.
diff --git a/index.html b/index.html
index 8bfebe0..93b2120 100644
--- a/index.html
+++ b/index.html
@@ -240,6 +240,13 @@
                 <input type="checkbox" id="debug-editor-toggle" />
                 <span>Editor mode</span>
               </label>
+              <label class="debug-row">
+                <span>Editor layout</span>
+                <select id="debug-editor-layout">
+                  <option value="desktop">Desktop</option>
+                  <option value="mobile">Mobile</option>
+                </select>
+              </label>
               <label class="debug-row debug-toggle">
                 <input type="checkbox" id="debug-monochrome" />
                 <span>Force monochrome</span>
diff --git a/src/editor/EditorRoot.test.ts b/src/editor/EditorRoot.test.ts
index 0cf43ec..5a21ce1 100644
--- a/src/editor/EditorRoot.test.ts
+++ b/src/editor/EditorRoot.test.ts
@@ -36,7 +36,8 @@ import {
   ,
   buildAutomationTrackPolyline
   ,
-  zoomPlaylistTrackHeight
+  zoomPlaylistTrackHeight,
+  getEditorLayoutClass
 } from "./EditorRoot";
 
 describe("formatTime", () => {
@@ -51,6 +52,14 @@ describe("formatTime", () => {
   });
 });
 
+describe("getEditorLayoutClass", () => {
+  it("returns mobile modifier class only for mobile layout mode", () => {
+    expect(getEditorLayoutClass("mobile")).toBe("editor editor--mobile");
+    expect(getEditorLayoutClass("desktop")).toBe("editor");
+    expect(getEditorLayoutClass(undefined)).toBe("editor");
+  });
+});
+
 describe("getClipPercent", () => {
   it("returns clip left and width percentage from start/end/duration", () => {
     expect(getClipPercent(10, 30, 100)).toEqual({ left: 10, width: 20 });
diff --git a/src/editor/EditorRoot.ts b/src/editor/EditorRoot.ts
index 350c867..22c6a1e 100644
--- a/src/editor/EditorRoot.ts
+++ b/src/editor/EditorRoot.ts
@@ -115,6 +115,7 @@ const MAIN_SLOT_LABELS: Array<{ slot: MainSlot; label: string }> = [
 type EditorInit = {
   container: HTMLElement;
   effectNames: string[];
+  layoutMode?: "desktop" | "mobile";
   applyTimeline: (raw: RawTimelineConfig) => Promise<string | null>;
   play: () => Promise<void>;
   pause: () => void;
@@ -123,6 +124,10 @@ type EditorInit = {
   getAudioDuration: () => number;
 };
 
+export const getEditorLayoutClass = (layoutMode: EditorInit["layoutMode"]): string => {
+  return layoutMode === "mobile" ? "editor editor--mobile" : "editor";
+};
+
 export type EditorController = {
   setVisible: (visible: boolean) => void;
   isVisible: () => boolean;
@@ -905,6 +910,7 @@ export async function createEditorRoot(init: EditorInit): Promise<EditorControll
     const previousSceneList = init.container.querySelector<HTMLDivElement>(".editor-scene-list");
     const sceneListScrollTop = previousSceneList?.scrollTop ?? 0;
 
+    init.container.className = getEditorLayoutClass(init.layoutMode);
     init.container.innerHTML = `
       <div class="editor-header">
         <div class="editor-title">SCENE + TIMELINE EDITOR</div>
diff --git a/src/main.ts b/src/main.ts
index 1b0d592..65fb8ba 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -134,6 +134,7 @@ const debugSkipEndButton = document.querySelector<HTMLButtonElement>("#debug-ski
 const debugSkipBackButton = document.querySelector<HTMLButtonElement>("#debug-skip-back");
 const debugSkipForwardButton = document.querySelector<HTMLButtonElement>("#debug-skip-forward");
 const debugEditorToggle = document.querySelector<HTMLInputElement>("#debug-editor-toggle");
+const debugEditorLayoutSelect = document.querySelector<HTMLSelectElement>("#debug-editor-layout");
 const debugTabButtons = Array.from(document.querySelectorAll<HTMLButtonElement>("[data-debug-tab]"));
 const editorRoot = document.querySelector<HTMLDivElement>("#editor-root");
 const mobileControls = document.querySelector<HTMLDivElement>("#mobile-controls");
@@ -181,6 +182,7 @@ const effectIdeaSubmitButton = document.querySelector<HTMLButtonElement>("#effec
 const queryParams = new URLSearchParams(window.location.search);
 const releaseMode = queryParams.get("release") === "1";
 const editorModeFromQuery = queryParams.get("editor") === "1";
+const editorLayoutFromQuery = queryParams.get("editorLayout") === "mobile" ? "mobile" : "desktop";
 const renderSettings = getRenderSettings(queryParams);
 const qualityState = createQualityState(renderSettings.qualityScale, renderSettings.autoQuality);
 const initialQualityPresetId = resolveInitialQualityPresetId(qualityState.qualityScale, qualityState.autoQuality);
@@ -213,6 +215,7 @@ let isRunning = false;
 let pendingConfig: TimelineConfig | null = null;
 let currentAudioSrc = "";
 let editorController: EditorController | null = null;
+let editorLayoutMode: "desktop" | "mobile" = editorLayoutFromQuery;
 let lastFrameTimestamp = performance.now();
 let currentViewCount = 0;
 let overlayMode: OverlayMode = "start";
@@ -1732,9 +1735,10 @@ if (!releaseMode) {
     if (!editorRoot) {
       return;
     }
-    createEditorRoot({
+    const initEditor = (): Promise<EditorController> => createEditorRoot({
       container: editorRoot,
       effectNames: availableEffectNames,
+      layoutMode: editorLayoutMode,
       applyTimeline: applyRawTimeline,
       play: async () => {
         if (!audioPlayer) {
@@ -1760,7 +1764,9 @@ if (!releaseMode) {
       },
       getAudioOffset: () => timeline?.getAudioOffset() ?? 0,
       getAudioDuration: () => audioPlayer?.duration ?? 0
-    }).then((controller) => {
+    });
+
+    initEditor().then((controller) => {
       editorController = controller;
       if (debugEditorToggle) {
         debugEditorToggle.checked = editorModeFromQuery;
@@ -1768,6 +1774,16 @@ if (!releaseMode) {
           controller.setVisible(debugEditorToggle.checked);
         });
       }
+      if (debugEditorLayoutSelect) {
+        debugEditorLayoutSelect.value = editorLayoutMode;
+        debugEditorLayoutSelect.addEventListener("change", () => {
+          editorLayoutMode = debugEditorLayoutSelect.value === "mobile" ? "mobile" : "desktop";
+          void initEditor().then((nextController) => {
+            editorController = nextController;
+            nextController.setVisible(debugEditorToggle?.checked ?? editorModeFromQuery);
+          });
+        });
+      }
       controller.setVisible(debugEditorToggle?.checked ?? editorModeFromQuery);
     });
   })();
diff --git a/src/style.css b/src/style.css
index 3e16558..cd61007 100644
--- a/src/style.css
+++ b/src/style.css
@@ -1321,6 +1321,28 @@ body,
   z-index: 2;
 }
 
+.editor--mobile .editor-body {
+  grid-template-columns: minmax(0, 1fr);
+  grid-template-areas:
+    "workspace"
+    "scenes"
+    "inspector";
+}
+
+.editor--mobile .editor-top-row {
+  grid-template-columns: minmax(0, 1fr);
+}
+
+.editor--mobile .editor-preview canvas {
+  width: 100%;
+  height: auto;
+}
+
+.editor--mobile .editor-scenes,
+.editor--mobile .editor-inspector {
+  max-height: none;
+}
+
 .editor-transport-row {
   display: flex;
   align-items: center;