diff --git a/backend/app/main.py b/backend/app/main.py
index 8546208..c152ba2 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -1943,10 +1943,16 @@ def select_public_ask_questions(task_no: str, payload: dict, db: Session = Depen
     used_ids = {item.question_id for item in assignment.used_questions}
     if selected_ids & used_ids:
         raise HTTPException(status_code=400, detail="已认领的问题不能重复选择")
-    for item in assignment.items:
-        # The selection represents only the next batch. Questions in
-        # ``used_ids`` remain locked/read-only and are not resubmitted.
-        item.selected = item.question_id in selected_ids
+    for item in list(assignment.items):
+        # Keep historical submitted questions for batch details, retain only
+        # the questions confirmed for this batch, and immediately return all
+        # other provisional questions to the public pool.
+        if item.question_id in used_ids:
+            item.selected = False
+        elif item.question_id in selected_ids:
+            item.selected = True
+        else:
+            db.delete(item)
     assignment.status = "进行中"
     assignment.reservation_started_at = datetime.utcnow()
     assignment.updated_at = assignment.reservation_started_at
diff --git a/backend/tests/test_auth.py b/backend/tests/test_auth.py
index e691c06..b8020bc 100644
--- a/backend/tests/test_auth.py
+++ b/backend/tests/test_auth.py
@@ -1138,6 +1138,57 @@ def test_public_ask_questions_are_unique_across_users_and_eventually_exhausted()
         assert exhausted.json()["detail"] == "本次任务已被领取完，请关注下一个任务！"
 
 
+def test_unselected_ask_questions_are_released_immediately(monkeypatch):
+    monkeypatch.setattr(main_module, "generate_questions", fake_ask_questions)
+    with TestClient(app) as client:
+        assert client.post(
+            "/api/admin/auth/login",
+            json={"username": "operator", "password": "operator123456"},
+        ).status_code == 200
+        generated = client.post(
+            "/api/admin/ask-tasks/generate",
+            json={
+                "shop_name": "未领取释放测试店铺",
+                "product_link": "TOKEN-RELEASE-UNSELECTED",
+                "product_name": "未领取释放测试商品",
+                "question_count": 8,
+            },
+        ).json()["data"]
+        assert client.post(f"/api/admin/ask-tasks/{generated['id']}/publish").status_code == 200
+
+        first_session = client.post(
+            "/api/ask/auth/taobao-login",
+            json={"taobao_id": f"tb{uuid4().hex[:14]}"},
+        ).json()["data"]
+        second_session = client.post(
+            "/api/ask/auth/taobao-login",
+            json={"taobao_id": f"tb{uuid4().hex[:14]}"},
+        ).json()["data"]
+        first_url = f"/api/ask/tasks/{generated['task_id']}?token={first_session['token']}"
+        first_assignment = client.get(first_url).json()["data"]
+        first_ids = {item["id"] for item in first_assignment["questions"]}
+        assert len(first_ids) == 5
+
+        selected_ids = set(list(first_ids)[:3])
+        confirmed = client.post(
+            f"/api/ask/tasks/{generated['task_id']}/selection",
+            json={"token": first_session["token"], "question_ids": list(selected_ids)},
+        )
+        assert confirmed.status_code == 200
+        confirmed_ids = {item["id"] for item in confirmed.json()["data"]["questions"]}
+        assert confirmed_ids == selected_ids
+
+        second_url = f"/api/ask/tasks/{generated['task_id']}?token={second_session['token']}"
+        second_assignment = client.get(second_url)
+        assert second_assignment.status_code == 200
+        second_ids = {item["id"] for item in second_assignment.json()["data"]["questions"]}
+        assert len(second_ids) == 5
+        assert second_ids == {
+            item["id"]
+            for item in generated["selected_questions"]
+        } - selected_ids
+
+
 def test_answer_submission_requires_owner_link_and_allows_at_most_two_images():
     with TestClient(app) as client:
         missing_owner = client.post(
diff --git a/frontend/src/admin.css b/frontend/src/admin.css
index 7646963..9b31cdb 100644
--- a/frontend/src/admin.css
+++ b/frontend/src/admin.css
@@ -5485,48 +5485,97 @@ body img {
 .global-image-viewer {
   position: fixed;
   z-index: 9999;
-  inset: 0;
+  top: 84px;
+  right: 18px;
+  bottom: 18px;
   display: grid;
-  place-items: center;
-  padding: 32px;
-  background: rgba(4, 12, 28, .82);
-  cursor: zoom-out;
+  grid-template-rows: auto minmax(0, 1fr) auto;
+  width: min(480px, calc(100vw - 36px));
+  border: 1px solid #cbd8e8;
+  border-radius: 10px;
+  background: #fff;
+  box-shadow: 0 18px 55px rgba(8, 24, 50, .28);
   overflow: hidden;
 }
 
-.global-image-viewer img {
+.global-image-viewer.left {
+  right: auto;
+  left: 18px;
+}
+
+.global-image-viewer-header {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  min-height: 56px;
+  padding: 10px 12px 10px 15px;
+  border-bottom: 1px solid #dce5ef;
+  background: #fff;
+  cursor: grab;
+  touch-action: none;
+  user-select: none;
+}
+
+.global-image-viewer.dragging-window .global-image-viewer-header {
+  cursor: grabbing;
+}
+
+.global-image-viewer-header > div {
+  display: grid;
+  min-width: 0;
+  flex: 1;
+  gap: 3px;
+}
+
+.global-image-viewer-header strong {
+  color: #102744;
+  font-size: 14px;
+}
+
+.global-image-viewer-header span {
+  color: #7187a1;
+  font-size: 11px;
+}
+
+.global-image-viewer-canvas {
+  display: grid;
+  place-items: center;
+  min-height: 0;
+  padding: 14px;
+  overflow: hidden;
+  background: #eaf0f7;
+  overscroll-behavior: contain;
+}
+
+.global-image-viewer-canvas img {
   display: block;
-  max-width: min(94vw, 1600px);
-  max-height: 92vh;
+  max-width: 100%;
+  max-height: 100%;
   width: auto;
   height: auto;
   object-fit: contain;
-  border-radius: 10px;
-  box-shadow: 0 20px 80px rgba(0, 0, 0, .45);
+  border-radius: 6px;
+  box-shadow: 0 10px 32px rgba(8, 24, 50, .2);
   cursor: grab;
   touch-action: none;
   transform-origin: center center;
   user-select: none;
 }
 
-.global-image-viewer img.dragging {
+.global-image-viewer-canvas img.dragging {
   cursor: grabbing;
 }
 
 .global-image-viewer-tools {
-  position: fixed;
-  z-index: 2;
-  left: 50%;
-  bottom: 22px;
   display: flex;
   align-items: center;
+  justify-content: center;
   gap: 8px;
-  padding: 6px 8px;
-  border: 1px solid rgba(255, 255, 255, .2);
-  border-radius: 10px;
-  background: rgba(13, 28, 51, .88);
+  min-height: 50px;
+  padding: 8px 12px;
+  border-top: 1px solid rgba(255, 255, 255, .16);
+  background: #0d1c33;
   color: #fff;
-  transform: translateX(-50%);
 }
 
 .global-image-viewer-tools button {
@@ -5546,6 +5595,26 @@ body img {
   background: rgba(255, 255, 255, .24);
 }
 
+.global-image-viewer-tools button:disabled {
+  opacity: .35;
+  cursor: not-allowed;
+}
+
+.global-image-viewer-tools button.gallery-nav {
+  min-width: 68px;
+  font-size: 11px;
+}
+
+.global-image-viewer-tools span.gallery-count {
+  min-width: 36px;
+}
+
+.global-image-viewer-tools i {
+  width: 1px;
+  height: 22px;
+  background: rgba(255, 255, 255, .22);
+}
+
 .global-image-viewer-tools button.reset {
   font-size: 12px;
 }
@@ -5614,33 +5683,69 @@ body img {
 }
 
 .global-image-viewer-close {
-  position: fixed;
-  top: 18px;
-  right: 22px;
-  z-index: 1;
-  width: 40px;
-  height: 40px;
-  border: 1px solid rgba(255, 255, 255, .35);
-  border-radius: 50%;
-  background: rgba(255, 255, 255, .12);
-  color: #fff;
-  font-size: 28px;
+  display: grid;
+  place-items: center;
+  width: 34px;
+  height: 34px;
+  padding: 0;
+  border: 1px solid #d5e0ec;
+  border-radius: 7px;
+  background: #f4f7fa;
+  color: #536d8b;
+  font-size: 22px;
   line-height: 1;
   cursor: pointer;
 }
 
-@media (max-width: 640px) {
-  .global-image-viewer {
-    padding: 16px;
+.global-image-viewer-dock {
+  display: grid;
+  place-items: center;
+  width: 34px;
+  height: 34px;
+  padding: 0;
+  border: 1px solid #d5e0ec;
+  border-radius: 7px;
+  background: #f4f7fa;
+  color: #1764e8;
+  font-size: 18px;
+  cursor: pointer;
+}
+
+@media (min-width: 1201px) {
+  body.image-preview-right .review-v2-backdrop {
+    padding-right: 516px;
+    justify-items: end;
   }
 
-  .global-image-viewer-close {
-    top: 12px;
-    right: 12px;
+  body.image-preview-left .review-v2-backdrop {
+    padding-left: 516px;
+    justify-items: start;
+  }
+}
+
+@media (max-width: 1200px) {
+  .global-image-viewer,
+  .global-image-viewer.left {
+    top: auto;
+    right: 10px;
+    bottom: calc(10px + env(safe-area-inset-bottom));
+    left: 10px;
+    width: auto;
+    height: min(48dvh, 480px);
+  }
+
+  .global-image-viewer-dock {
+    display: none;
   }
 
   .global-image-viewer-tools {
-    bottom: 14px;
+    flex-wrap: wrap;
+    gap: 5px;
+    padding-inline: 8px;
+  }
+
+  .global-image-viewer-tools i {
+    display: none;
   }
 }
 
diff --git a/frontend/src/main.jsx b/frontend/src/main.jsx
index 2b163e7..ade568a 100644
--- a/frontend/src/main.jsx
+++ b/frontend/src/main.jsx
@@ -1,6 +1,7 @@
 import React, { useEffect, useRef, useState } from "react";
 import { createRoot } from "react-dom/client";
 import {
+  BookOpen,
   ClipboardList,
   Database,
   FileText,
@@ -326,6 +327,13 @@ const BASE_ITEMS = [
     label: "\u5ba1\u6838\u4e2d\u5fc3",
     group: "\u4efb\u52a1\u7ba1\u7406",
   },
+  {
+    id: "guide",
+    icon: BookOpen,
+    label: "\u4f7f\u7528\u8bf4\u660e",
+    group: "\u4efb\u52a1\u7ba1\u7406",
+    href: "https://alidocs.dingtalk.com/i/nodes/amweZ92PV6w4kNGdcqEmwAMYJxEKBD6p?corpId=dinga78635fdab496f8735c2f4657eb6378f&doc_type=wiki_doc&editNotify=true&iframeQuery=utm_medium=im_card&utm_source=im&utm_medium=im_card&utm_scene=team_space&utm_source=im",
+  },
 ];
 const ADMIN_ITEMS = [
   {
@@ -394,6 +402,21 @@ function Sidebar({ user, active, setActive, reviewBadge }) {
 }
 function NavItem({ item, active, setActive }) {
   const Icon = item.icon;
+  if (item.href) {
+    return (
+      <a
+        className="nav-item"
+        href={item.href}
+        target="_blank"
+        rel="noopener noreferrer"
+        title="在新标签页打开使用说明"
+      >
+        <Icon size={17} />
+        <span>{item.label}</span>
+        <em aria-hidden="true">↗</em>
+      </a>
+    );
+  }
   return (
     <button
       className={`nav-item ${active === item.id ? "active" : ""}`}
@@ -3936,21 +3959,41 @@ function CompletionReviewPage() {
   );
 }
 function GlobalImageViewer() {
-  const [src, setSrc] = useState("");
+  const [gallery, setGallery] = useState([]);
+  const [currentIndex, setCurrentIndex] = useState(-1);
   const [scale, setScale] = useState(1);
   const [position, setPosition] = useState({ x: 0, y: 0 });
   const [dragging, setDragging] = useState(false);
+  const [dockSide, setDockSide] = useState("right");
+  const [floatingPosition, setFloatingPosition] = useState(null);
+  const [panelDragging, setPanelDragging] = useState(false);
+  const panelRef = useRef(null);
+  const panelDragStart = useRef(null);
   const dragStart = useRef(null);
+  const src = gallery[currentIndex]?.src || "";
   useEffect(() => {
     const handleClick = (event) => {
       const image = event.target?.closest?.("img");
-      if (!image || !image.src) return;
-      setSrc(image.src);
+      if (!image || !image.src || image.closest(".global-image-viewer")) return;
+      const scope = image.closest(".review-v2-modal") || document;
+      const imageNodes = Array.from(scope.querySelectorAll("img")).filter(
+        (node) => node.src && !node.closest(".global-image-viewer"),
+      );
+      const items = imageNodes.map((node) => ({
+        src: node.currentSrc || node.src,
+        alt: node.alt || "审核图片",
+      }));
+      setGallery(items);
+      setCurrentIndex(Math.max(0, imageNodes.indexOf(image)));
       setScale(1);
       setPosition({ x: 0, y: 0 });
     };
     const handleKeyDown = (event) => {
-      if (event.key === "Escape") setSrc("");
+      if (event.key === "Escape") {
+        setGallery([]);
+        setCurrentIndex(-1);
+        setFloatingPosition(null);
+      }
     };
     document.addEventListener("click", handleClick);
     document.addEventListener("keydown", handleKeyDown);
@@ -3959,6 +4002,31 @@ function GlobalImageViewer() {
       document.removeEventListener("keydown", handleKeyDown);
     };
   }, []);
+  useEffect(() => {
+    if (!src) return undefined;
+    const handleGalleryKeyDown = (event) => {
+      if (event.key === "ArrowLeft") {
+        setCurrentIndex((current) => Math.max(0, current - 1));
+      }
+      if (event.key === "ArrowRight") {
+        setCurrentIndex((current) => Math.min(gallery.length - 1, current + 1));
+      }
+    };
+    document.addEventListener("keydown", handleGalleryKeyDown);
+    return () => document.removeEventListener("keydown", handleGalleryKeyDown);
+  }, [src, gallery.length]);
+  useEffect(() => {
+    if (!src) return;
+    setScale(1);
+    setPosition({ x: 0, y: 0 });
+  }, [currentIndex, src]);
+  useEffect(() => {
+    document.body.classList.remove("image-preview-left", "image-preview-right");
+    if (!src) return undefined;
+    const className = `image-preview-${dockSide}`;
+    document.body.classList.add(className);
+    return () => document.body.classList.remove(className);
+  }, [src, dockSide]);
   if (!src) return null;
   const changeScale = (delta) => {
     setScale((current) => {
@@ -3991,38 +4059,131 @@ function GlobalImageViewer() {
     dragStart.current = null;
     setDragging(false);
   };
+  const closeViewer = () => {
+    setGallery([]);
+    setCurrentIndex(-1);
+    setFloatingPosition(null);
+  };
+  const showImage = (nextIndex) => {
+    if (nextIndex < 0 || nextIndex >= gallery.length) return;
+    setCurrentIndex(nextIndex);
+  };
+  const beginPanelDrag = (event) => {
+    if (event.button !== 0 || event.target.closest("button") || !panelRef.current) return;
+    const rect = panelRef.current.getBoundingClientRect();
+    event.currentTarget.setPointerCapture?.(event.pointerId);
+    panelDragStart.current = {
+      pointerX: event.clientX,
+      pointerY: event.clientY,
+      left: rect.left,
+      top: rect.top,
+      width: rect.width,
+      height: rect.height,
+    };
+    setPanelDragging(true);
+  };
+  const movePanelDrag = (event) => {
+    if (!panelDragStart.current) return;
+    const start = panelDragStart.current;
+    const margin = 8;
+    const left = Math.min(
+      window.innerWidth - start.width - margin,
+      Math.max(margin, start.left + event.clientX - start.pointerX),
+    );
+    const top = Math.min(
+      window.innerHeight - start.height - margin,
+      Math.max(margin, start.top + event.clientY - start.pointerY),
+    );
+    setFloatingPosition({ left, top, height: start.height });
+  };
+  const endPanelDrag = () => {
+    panelDragStart.current = null;
+    setPanelDragging(false);
+  };
+  const switchDockSide = () => {
+    setFloatingPosition(null);
+    setDockSide((current) => current === "right" ? "left" : "right");
+  };
   return (
-    <div
-      className="global-image-viewer"
-      role="dialog"
-      aria-modal="true"
-      aria-label="图片大图预览"
-      onClick={() => setSrc("")}
-      onWheel={(event) => {
-        event.preventDefault();
-        changeScale(event.deltaY > 0 ? -0.15 : 0.15);
-      }}
+    <aside
+      ref={panelRef}
+      className={`global-image-viewer ${dockSide === "left" ? "left" : ""}${panelDragging ? " dragging-window" : ""}`}
+      role="complementary"
+      aria-label="图片预览"
+      style={floatingPosition ? {
+        left: `${floatingPosition.left}px`,
+        top: `${floatingPosition.top}px`,
+        right: "auto",
+        bottom: "auto",
+        height: `${floatingPosition.height}px`,
+      } : undefined}
     >
-      <button type="button" className="global-image-viewer-close" aria-label="关闭大图" onClick={() => setSrc("")}>×</button>
-      <div className="global-image-viewer-tools" onClick={(event) => event.stopPropagation()}>
+      <header
+        className="global-image-viewer-header"
+        onPointerDown={beginPanelDrag}
+        onPointerMove={movePanelDrag}
+        onPointerUp={endPanelDrag}
+        onPointerCancel={endPanelDrag}
+      >
+        <div>
+          <strong>图片预览</strong>
+          <span>拖动标题栏可移动 · 页面仍可滚动</span>
+        </div>
+        <button
+          type="button"
+          className="global-image-viewer-dock"
+          aria-label={dockSide === "right" ? "将预览移到左侧" : "将预览移到右侧"}
+          title={dockSide === "right" ? "移到左侧" : "移到右侧"}
+          onClick={switchDockSide}
+        >
+          {dockSide === "right" ? "←" : "→"}
+        </button>
+        <button type="button" className="global-image-viewer-close" aria-label="关闭预览" onClick={closeViewer}>×</button>
+      </header>
+      <div
+        className="global-image-viewer-canvas"
+        onWheel={(event) => {
+          event.preventDefault();
+          changeScale(event.deltaY > 0 ? -0.15 : 0.15);
+        }}
+      >
+        <img
+          src={src}
+          alt="大图预览"
+          draggable={false}
+          className={dragging ? "dragging" : ""}
+          style={{ transform: `translate(${position.x}px, ${position.y}px) scale(${scale})` }}
+          onPointerDown={beginDrag}
+          onPointerMove={moveDrag}
+          onPointerUp={endDrag}
+          onPointerCancel={endDrag}
+        />
+      </div>
+      <div className="global-image-viewer-tools">
+        <button
+          type="button"
+          className="gallery-nav"
+          disabled={currentIndex <= 0}
+          onClick={() => showImage(currentIndex - 1)}
+        >
+          ← 上一张
+        </button>
+        <span className="gallery-count">{currentIndex + 1}/{gallery.length}</span>
+        <button
+          type="button"
+          className="gallery-nav"
+          disabled={currentIndex >= gallery.length - 1}
+          onClick={() => showImage(currentIndex + 1)}
+        >
+          下一张 →
+        </button>
+        <i aria-hidden="true" />
         <button type="button" aria-label="缩小" onClick={() => changeScale(-0.25)}>−</button>
         <span>{Math.round(scale * 100)}%</span>
         <button type="button" aria-label="放大" onClick={() => changeScale(0.25)}>＋</button>
         <button type="button" className="reset" onClick={resetView}>重置</button>
       </div>
-      <img
-        src={src}
-        alt="大图预览"
-        draggable={false}
-        className={dragging ? "dragging" : ""}
-        style={{ transform: `translate(${position.x}px, ${position.y}px) scale(${scale})` }}
-        onClick={(event) => event.stopPropagation()}
-        onPointerDown={beginDrag}
-        onPointerMove={moveDrag}
-        onPointerUp={endDrag}
-        onPointerCancel={endDrag}
-      />
-    </div>
+    </aside>
   );
 }
 
diff --git a/frontend/src/styles.css b/frontend/src/styles.css
index dad4195..565dc4e 100644
--- a/frontend/src/styles.css
+++ b/frontend/src/styles.css
@@ -313,6 +313,7 @@ button {
   color: #c5d2e8;
   background: transparent;
   text-align: left;
+  text-decoration: none;
 }
 .nav-item:hover,
 .nav-item.active {