FN-6377: make tablet modals touch-resizable

Enable shared resize handles for modals on tablet and desktop while keeping mobile sheets full-screen.

- Add a pointer-driven resize grip to useModalResizePersist with debounced persistence and mobile cleanup.
- Widen the task-detail modal tablet default to 96vw / 1024px.
- Cover resize behavior and tablet width expectations with dashboard tests.
- Document the shared modal resize pattern and add the published package changeset.

Files changed:
 .changeset/FN-6377-tablet-resizable-modals.md      |   5 +
 docs/dashboard-guide.md                            |   2 +-
 .../task-detail-modal-tablet-width.test.ts         |   4 +-
 .../dashboard/app/components/TaskDetailModal.css   |   4 +-
 .../hooks/__tests__/useModalResizePersist.test.tsx | 218 +++++++++++++++++++++
 .../dashboard/app/hooks/useModalResizePersist.ts   | 140 ++++++++++---
 packages/dashboard/app/styles.css                  |  36 ++++
 7 files changed, 382 insertions(+), 27 deletions(-)

Fusion-Task-Id: FN-6377

Fusion-Task-Lineage: ecc12aa4-f881-4476-a69b-13d34a73e263

.changeset/FN-6377-tablet-resizable-modals.md

@@ -0,0 +1,5 @@
+---
+"@runfusion/fusion": minor
+---
+
+Make dashboard modals touch-resizable on tablet and widen the task-detail modal default tablet width.

docs/dashboard-guide.md

@@ -1190,7 +1190,7 @@ Dark/light modes via `data-theme`; 54 color themes via `data-color-theme` (lazy-
 
 Reuse existing primitives from `styles.css`:
 - **Buttons**: `.btn`, `.btn-primary`, `.btn-danger`, `.btn-warning`, `.btn-sm`, `.btn-icon`, `.btn-icon--active`, `.btn-badge`. All inherit `:focus-visible` via `--focus-ring-strong` and `:active` via `transform: scale(0.97)`.
-- **Modals**: `.modal-overlay[.open]`, `.modal`, `.modal-lg`, `.modal-header`, `.modal-close`, `.modal-actions`, `.modal-actions-left/right`. Overlay pads top with `--overlay-padding-top`. Overlay dialogs should render through `createPortal(..., document.body)` so `position: fixed` overlays escape transformed, contained, or fixed ancestors.
+- **Modals**: `.modal-overlay[.open]`, `.modal`, `.modal-lg`, `.modal-header`, `.modal-close`, `.modal-actions`, `.modal-actions-left/right`. Overlay pads top with `--overlay-padding-top`. Overlay dialogs should render through `createPortal(..., document.body)` so `position: fixed` overlays escape transformed, contained, or fixed ancestors. Resizable modals using `useModalResizePersist(...)` get a shared bottom-right touch/mouse resize grip on tablet and desktop; mobile sheets stay full-screen and grip-free.
 - **Forms**: `.form-group`, `.input`, `.select`, `.checkbox-label`, `.form-error`. Inputs in `.form-group` get focus styles automatically.
 - **Cards**: `.card`, `.card-header`, `.card-id`, `.card-title`, `.card-meta`, `.card-status-badge--{triage,todo,in-progress,in-review,done,archived}`.
 - **Utility**: `.touch-target` (44px min), `.visually-hidden`.

packages/dashboard/app/__tests__/task-detail-modal-tablet-width.test.ts

@@ -23,8 +23,8 @@ describe("task detail modal tablet width (FN-5599)", () => {
     const tabletBlock = tabletBlockMatch![1];
     const modalRuleMatch = tabletBlock.match(/\.modal\.task-detail-modal\s*\{[^}]*\}/s);
     expect(modalRuleMatch).toBeTruthy();
-    expect(modalRuleMatch![0]).toContain("width: min(92vw, 960px);");
+    expect(modalRuleMatch![0]).toContain("width: min(96vw, 1024px);");
-    expect(modalRuleMatch![0]).toContain("max-width: 92vw;");
+    expect(modalRuleMatch![0]).toContain("max-width: 96vw;");
   });
 
   it("keeps mobile full-screen sheet width behavior", () => {

packages/dashboard/app/components/TaskDetailModal.css

@@ -939,8 +939,8 @@
 /* FN-5599: widen task detail modal on tablet viewports. */
 @media (min-width: 769px) and (max-width: 1024px) {
   .modal.task-detail-modal {
-    width: min(92vw, 960px);
+    width: min(96vw, 1024px);
-    max-width: 92vw;
+    max-width: 96vw;
     height: 92vh;
     max-height: calc(100dvh - var(--overlay-padding-top, 6vh) - 16px);
   }

packages/dashboard/app/hooks/__tests__/useModalResizePersist.test.tsx

@@ -0,0 +1,218 @@
+import { render, screen } from "@testing-library/react";
+import { useRef } from "react";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import { useModalResizePersist } from "../useModalResizePersist";
+
+const STORAGE_KEY = "fusion:test-modal-size";
+
+type ResizeObserverCallback = ConstructorParameters<typeof ResizeObserver>[0];
+
+const resizeObserverCallbacks = new Set<ResizeObserverCallback>();
+
+class MockResizeObserver implements ResizeObserver {
+  readonly callback: ResizeObserverCallback;
+
+  constructor(callback: ResizeObserverCallback) {
+    this.callback = callback;
+    resizeObserverCallbacks.add(callback);
+  }
+
+  observe = vi.fn();
+  unobserve = vi.fn();
+
+  disconnect = vi.fn(() => {
+    resizeObserverCallbacks.delete(this.callback);
+  });
+}
+
+function setViewport(width: number, height = 800): void {
+  Object.defineProperty(window, "innerWidth", { configurable: true, value: width });
+  Object.defineProperty(window, "innerHeight", { configurable: true, value: height });
+  Object.defineProperty(window, "screen", {
+    configurable: true,
+    value: { width, height },
+  });
+  window.matchMedia = vi.fn((query: string) => ({
+    matches: query.includes("max-width: 768px")
+      ? width <= 768
+      : query.includes("max-height: 480px")
+        ? height <= 480
+        : query.includes("min-width: 769px") && query.includes("max-width: 1024px")
+          ? width >= 769 && width <= 1024
+          : false,
+    media: query,
+    onchange: null,
+    addEventListener: vi.fn(),
+    removeEventListener: vi.fn(),
+    addListener: vi.fn(),
+    removeListener: vi.fn(),
+    dispatchEvent: vi.fn(),
+  })) as typeof window.matchMedia;
+}
+
+function dispatchPointerEvent(
+  target: EventTarget,
+  type: string,
+  init: { clientX: number; clientY: number; pointerId?: number; pointerType?: string },
+): void {
+  const event = new Event(type, { bubbles: true, cancelable: true }) as PointerEvent;
+  Object.defineProperties(event, {
+    clientX: { value: init.clientX },
+    clientY: { value: init.clientY },
+    pointerId: { value: init.pointerId ?? 1 },
+    pointerType: { value: init.pointerType ?? "touch" },
+  });
+  target.dispatchEvent(event);
+}
+
+function installModalGeometry(node: HTMLElement, width = 500, height = 400): void {
+  Object.defineProperty(node, "offsetWidth", {
+    configurable: true,
+    get: () => Number.parseFloat(node.style.width) || width,
+  });
+  Object.defineProperty(node, "offsetHeight", {
+    configurable: true,
+    get: () => Number.parseFloat(node.style.height) || height,
+  });
+  node.getBoundingClientRect = vi.fn(() => ({
+    x: 0,
+    y: 0,
+    top: 0,
+    left: 0,
+    right: node.offsetWidth,
+    bottom: node.offsetHeight,
+    width: node.offsetWidth,
+    height: node.offsetHeight,
+    toJSON: () => ({}),
+  }));
+}
+
+function triggerResizeObservers(): void {
+  for (const callback of resizeObserverCallbacks) {
+    callback([], {} as ResizeObserver);
+  }
+}
+
+function Harness({
+  initialHeight,
+  initialWidth,
+  isOpen = true,
+  storageKey = STORAGE_KEY,
+}: {
+  initialHeight?: string;
+  initialWidth?: string;
+  isOpen?: boolean;
+  storageKey?: string;
+}) {
+  const modalRef = useRef<HTMLDivElement | null>(null);
+  useModalResizePersist(modalRef, isOpen, storageKey);
+
+  return (
+    <div
+      data-testid="modal"
+      ref={modalRef}
+      className="modal"
+      style={{ width: initialWidth, height: initialHeight }}
+    />
+  );
+}
+
+describe("useModalResizePersist", () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+    localStorage.clear();
+    resizeObserverCallbacks.clear();
+    vi.stubGlobal("ResizeObserver", MockResizeObserver);
+  });
+
+  afterEach(() => {
+    vi.runOnlyPendingTimers();
+    vi.useRealTimers();
+    vi.unstubAllGlobals();
+    vi.restoreAllMocks();
+    document.body.style.userSelect = "";
+  });
+
+  it("injects a touch-capable resize grip on tablet and persists dragged size", () => {
+    setViewport(900);
+    render(<Harness />);
+
+    const modal = screen.getByTestId("modal");
+    installModalGeometry(modal);
+
+    const grip = modal.querySelector(".modal-resize-grip") as HTMLElement;
+    expect(grip).toBeTruthy();
+
+    expect(grip).toHaveAttribute("role", "separator");
+    expect(grip).toHaveAttribute("aria-label", "Resize modal from bottom-right corner");
+
+    dispatchPointerEvent(grip, "pointerdown", { clientX: 10, clientY: 20, pointerType: "touch" });
+    dispatchPointerEvent(document, "pointermove", { clientX: 70, clientY: 65, pointerType: "touch" });
+    dispatchPointerEvent(document, "pointerup", { clientX: 70, clientY: 65, pointerType: "touch" });
+
+    expect(modal.style.width).toBe("560px");
+    expect(modal.style.height).toBe("445px");
+
+    vi.advanceTimersByTime(200);
+    expect(JSON.parse(localStorage.getItem(STORAGE_KEY) ?? "{}"))
+      .toEqual({ width: 560, height: 445 });
+  });
+
+  it("keeps desktop grip and native ResizeObserver persistence/restore behavior", () => {
+    setViewport(1280);
+    localStorage.setItem(STORAGE_KEY, JSON.stringify({ width: 610, height: 480 }));
+
+    render(<Harness />);
+    const modal = screen.getByTestId("modal");
+    installModalGeometry(modal);
+
+    expect(modal.querySelector(".modal-resize-grip")).toBeTruthy();
+    expect(modal.style.width).toBe("610px");
+    expect(modal.style.height).toBe("480px");
+
+    modal.style.width = "640px";
+    modal.style.height = "500px";
+    triggerResizeObservers();
+    vi.advanceTimersByTime(200);
+
+    expect(JSON.parse(localStorage.getItem(STORAGE_KEY) ?? "{}"))
+      .toEqual({ width: 640, height: 500 });
+  });
+
+  it("clears inline size and does not inject a grip on mobile", () => {
+    setViewport(700);
+    localStorage.setItem(STORAGE_KEY, JSON.stringify({ width: 610, height: 480 }));
+
+    render(<Harness initialWidth="610px" initialHeight="480px" />);
+    const mobileModal = screen.getByTestId("modal");
+
+    expect(mobileModal.querySelector(".modal-resize-grip")).toBeNull();
+    expect(mobileModal.style.width).toBe("");
+    expect(mobileModal.style.height).toBe("");
+  });
+
+  it("removes the grip and drag listeners when closed or unmounted", () => {
+    setViewport(900);
+    const removeSpy = vi.spyOn(document, "removeEventListener");
+    const { rerender, unmount } = render(<Harness isOpen />);
+
+    const modal = screen.getByTestId("modal");
+    installModalGeometry(modal);
+    const grip = modal.querySelector(".modal-resize-grip") as HTMLElement;
+    expect(grip).toBeTruthy();
+
+    dispatchPointerEvent(grip, "pointerdown", { clientX: 10, clientY: 20 });
+    rerender(<Harness isOpen={false} />);
+
+    expect(modal.querySelector(".modal-resize-grip")).toBeNull();
+    expect(removeSpy).toHaveBeenCalledWith("pointermove", expect.any(Function));
+    expect(removeSpy).toHaveBeenCalledWith("pointerup", expect.any(Function));
+    expect(removeSpy).toHaveBeenCalledWith("pointercancel", expect.any(Function));
+
+    rerender(<Harness isOpen />);
+    expect(modal.querySelector(".modal-resize-grip")).toBeTruthy();
+    unmount();
+    expect(modal.querySelector(".modal-resize-grip")).toBeNull();
+  });
+});

packages/dashboard/app/hooks/useModalResizePersist.ts

@@ -1,10 +1,32 @@
 import { useEffect, type RefObject } from "react";
 
+import { isMobileViewport } from "./useViewportMode";
+
 interface PersistedSize {
   width?: number;
   height?: number;
 }
 
+const RESIZE_GRIP_CLASS = "modal-resize-grip";
+const RESIZE_GRIP_LABEL = "Resize modal from bottom-right corner";
+
+function readPersistableSize(node: HTMLElement): PersistedSize {
+  const styleWidth = Number.parseFloat(node.style.width);
+  const styleHeight = Number.parseFloat(node.style.height);
+  return {
+    width: node.offsetWidth > 0
+      ? node.offsetWidth
+      : Number.isFinite(styleWidth)
+        ? styleWidth
+        : undefined,
+    height: node.offsetHeight > 0
+      ? node.offsetHeight
+      : Number.isFinite(styleHeight)
+        ? styleHeight
+        : undefined,
+  };
+}
+
 /**
  * Persist a resizable modal's user-chosen dimensions across opens.
  *
@@ -37,13 +59,12 @@ export function useModalResizePersist(
     // would override the mobile CSS and leave the modal stuck at a partial
     // height. Skip restoration; also clear any width/height left over from
     // a prior desktop render of the same modal instance.
-    const isMobile =
+    const existingGrip = node.querySelector(`:scope > .${RESIZE_GRIP_CLASS}`);
-      typeof window !== "undefined" &&
+
-      ("ontouchstart" in window || navigator.maxTouchPoints > 0) &&
+    if (isMobileViewport()) {
-      window.innerWidth <= 768;
-    if (isMobile) {
       node.style.removeProperty("width");
       node.style.removeProperty("height");
+      existingGrip?.remove();
       return;
     }
 
@@ -59,34 +80,109 @@ export function useModalResizePersist(
       // ignore corrupted entry
     }
 
-    // jsdom (and very old browsers) lacks ResizeObserver — skip persistence
-    // gracefully rather than throw. Restoration above still ran.
-    if (typeof ResizeObserver === "undefined") return;
-
-    let lastSavedW = node.offsetWidth;
-    let lastSavedH = node.offsetHeight;
     let saveTimer: ReturnType<typeof setTimeout> | null = null;
-
+    const scheduleSave = () => {
-    const observer = new ResizeObserver(() => {
+      const { width, height } = readPersistableSize(node);
-      const w = node.offsetWidth;
+      if (typeof width !== "number" || typeof height !== "number") return;
-      const h = node.offsetHeight;
-      if (w === lastSavedW && h === lastSavedH) return;
-      lastSavedW = w;
-      lastSavedH = h;
       // Debounce so we don't spam localStorage during the drag.
       if (saveTimer) clearTimeout(saveTimer);
       saveTimer = setTimeout(() => {
         try {
-          localStorage.setItem(storageKey, JSON.stringify({ width: w, height: h }));
+          localStorage.setItem(storageKey, JSON.stringify({ width, height }));
         } catch {
           // quota / private mode — best-effort
         }
       }, 200);
-    });
+    };
+
+    let lastSavedW = node.offsetWidth;
+    let lastSavedH = node.offsetHeight;
+    const observer =
+      typeof ResizeObserver === "undefined"
+        ? null
+        : new ResizeObserver(() => {
+            const w = node.offsetWidth;
+            const h = node.offsetHeight;
+            if (w === lastSavedW && h === lastSavedH) return;
+            lastSavedW = w;
+            lastSavedH = h;
+            scheduleSave();
+          });
+
+    observer?.observe(node);
+
+    const grip = document.createElement("div");
+    grip.className = RESIZE_GRIP_CLASS;
+    grip.setAttribute("role", "separator");
+    grip.setAttribute("aria-label", RESIZE_GRIP_LABEL);
+    grip.dataset.resizeDirection = "se";
+    existingGrip?.remove();
+    node.appendChild(grip);
+
+    let cleanupActiveDrag: (() => void) | null = null;
+
+    const onPointerDown = (event: PointerEvent) => {
+      event.preventDefault();
+      event.stopPropagation();
+
+      if (typeof grip.setPointerCapture === "function") {
+        grip.setPointerCapture(event.pointerId);
+      }
+
+      const startRect = node.getBoundingClientRect();
+      const startWidth = startRect.width ||
+        node.offsetWidth ||
+        Number.parseFloat(node.style.width) ||
+        0;
+      const startHeight = startRect.height ||
+        node.offsetHeight ||
+        Number.parseFloat(node.style.height) ||
+        0;
+      const startX = event.clientX;
+      const startY = event.clientY;
+      const previousUserSelect = document.body.style.userSelect;
+      document.body.style.userSelect = "none";
+
+      const onPointerMove = (moveEvent: PointerEvent) => {
+        moveEvent.preventDefault();
+        const nextWidth = startWidth + moveEvent.clientX - startX;
+        const nextHeight = startHeight + moveEvent.clientY - startY;
+        if (nextWidth > 0) node.style.width = `${nextWidth}px`;
+        if (nextHeight > 0) node.style.height = `${nextHeight}px`;
+        scheduleSave();
+      };
+
+      const endDrag = (upEvent: PointerEvent) => {
+        if (typeof grip.releasePointerCapture === "function") {
+          grip.releasePointerCapture(upEvent.pointerId);
+        }
+        document.body.style.userSelect = previousUserSelect;
+        document.removeEventListener("pointermove", onPointerMove);
+        document.removeEventListener("pointerup", endDrag);
+        document.removeEventListener("pointercancel", endDrag);
+        scheduleSave();
+        cleanupActiveDrag = null;
+      };
+
+      cleanupActiveDrag = () => {
+        document.body.style.userSelect = previousUserSelect;
+        document.removeEventListener("pointermove", onPointerMove);
+        document.removeEventListener("pointerup", endDrag);
+        document.removeEventListener("pointercancel", endDrag);
+      };
+
+      document.addEventListener("pointermove", onPointerMove);
+      document.addEventListener("pointerup", endDrag);
+      document.addEventListener("pointercancel", endDrag);
+    };
+
+    grip.addEventListener("pointerdown", onPointerDown);
 
-    observer.observe(node);
     return () => {
-      observer.disconnect();
+      cleanupActiveDrag?.();
+      grip.removeEventListener("pointerdown", onPointerDown);
+      grip.remove();
+      observer?.disconnect();
       if (saveTimer) clearTimeout(saveTimer);
     };
   }, [ref, isOpen, storageKey]);

packages/dashboard/app/styles.css

@@ -1143,6 +1143,7 @@ body {
 }
 
 .modal {
+  position: relative;
   background: var(--surface);
   border: 1px solid var(--border);
   border-radius: var(--radius-lg);
@@ -1152,6 +1153,37 @@ body {
   display: flex;
   flex-direction: column;
 }
+
+.modal-resize-grip {
+  position: absolute;
+  right: 0;
+  bottom: 0;
+  z-index: 2;
+  width: var(--space-lg);
+  height: var(--space-lg);
+  cursor: se-resize;
+  touch-action: none;
+  background: transparent;
+}
+
+.modal-resize-grip::after {
+  content: "";
+  position: absolute;
+  right: var(--space-xs);
+  bottom: var(--space-xs);
+  width: var(--space-md);
+  height: var(--space-md);
+  border-right: var(--btn-border-width) solid var(--border);
+  border-bottom: var(--btn-border-width) solid var(--border);
+  opacity: 0;
+  transition: opacity var(--transition-fast);
+}
+
+.modal-resize-grip:hover::after,
+.modal-resize-grip:focus-visible::after,
+.modal-resize-grip:active::after {
+  opacity: 1;
+}
 .modal-lg {
   width: 640px;
 }
@@ -3433,6 +3465,10 @@ input[type="range"]:focus-visible {
     padding-bottom: env(safe-area-inset-bottom, 0px);
   }
 
+  .modal-resize-grip {
+    display: none;
+  }
+
   /* Settings modal: use the section picker as the only mobile navigation */
   .settings-layout {
     flex-direction: column;