diff --git a/docs/E18_VERSION_AND_DIFF_PROPOSAL.md b/docs/E18_VERSION_AND_DIFF_PROPOSAL.md
new file mode 100644
index 0000000..142ed7c
--- /dev/null
+++ b/docs/E18_VERSION_AND_DIFF_PROPOSAL.md
@@ -0,0 +1,336 @@
+# E18: 版本回滚 & AI 修改标记
+
+## 概述
+
+为编辑器的 AI 助手增加两个生产级功能：
+1. **版本回滚** — AI 修改前自动存档，错误时可恢复到任意历史版本
+2. **修改标记** — AI 修改后在 SceneGraph 节点上显示角标（新增/修改/删除），视觉可感知变更
+
+---
+
+## 一、版本回滚
+
+### 流程
+
+```
+用户发起 AI 请求
+  → buildMessage → POST /api/ai
+  → AIPanel.send() 在调用 sendAIRequest 前：
+      editorStore.saveVersion("AI 修改前")
+  → AI 修改完成 → reloadFromDisk() → gameData 刷新
+
+用户发现改错了
+  → AIPanel 版本下拉 → 选择历史版本
+  → editorStore.restoreVersion(index)
+  → gameData = version.gameData → autoSave()
+  → SceneGraph + NodeEditor 重绘
+```
+
+### 涉及文件
+
+| 文件 | 改动 |
+|------|------|
+| `editor/stores/editorStore.ts` | 新增 `versions` ref、`saveVersion(label)`、`restoreVersion(idx)` |
+| `editor/db/editorDB.ts` | **新建** — IndexedDB 封装：`put`/`get`/`clear`，按 `sourcePath` 分组 |
+| `editor/components/AIPanel.vue` | 新增版本下拉 UI（在聊天区顶部），send() 前调用 `saveVersion()` |
+
+### 版本数据结构
+
+```ts
+interface EditorVersion {
+  id: string            // crypto.randomUUID()
+  sourcePath: string    // "/scenes/demo.json"
+  timestamp: number     // Date.now()
+  label: string         // "AI 修改前" / "初始版本"
+  gameData: GameData    // 完整游戏数据快照
+}
+```
+
+### IndexedDB 设计
+
+```
+数据库: editor_versions
+表: versions
+索引: sourcePath (查询同一文件的所有版本)
+索引: timestamp (排序)
+```
+
+保留策略：同一 `sourcePath` 最多 20 个版本，超出删除最旧的。
+
+### editorDB.ts API
+
+```ts
+// 保存版本
+putVersion(v: EditorVersion): Promise<void>
+
+// 获取某文件的所有版本（按时间倒序）
+getVersions(sourcePath: string): Promise<EditorVersion[]>
+
+// 清除某文件的所有版本（切换文件时）
+clearVersions(sourcePath: string): Promise<void>
+```
+
+### 版本 UI 设计
+
+```
+AIPanel 顶部
+┌──────────────────────┐
+│ 历史版本: [AI 修改前 ▼]  │  ← 下拉列表，默认隐藏
+│ 2026-06-15 14:30 AI 修改前 │
+│ 2026-06-15 14:28 初始版本  │  ← restoreVersion 后刷新全部
+└──────────────────────┘
+```
+
+恢复后逻辑：
+1. `gameData = version.gameData`
+2. `autoSave()` 写回磁盘
+3. `selectedNodeId = null`（重置选中）
+4. AIPanel 聊天区显示 "已恢复到 'AI 修改前'"
+5. 不清除该版本快照（用户可能想在不同版本间多次切换）
+
+### saveVersion 触发时机
+
+| 时机 | 标签 |
+|------|------|
+| AI 模式 `send()` 调用前（`reloadFromDisk` 之前） | `"AI 修改前"` |
+| `App.vue` 首次加载 demo.json 后 | `"初始版本"` |
+
+不自动在手动编辑时保存版本（用户手动点"保存版本"按钮即可，可选后续添加）。
+
+---
+
+## 二、AI 修改标记
+
+### 流程
+
+```
+reloadFromDisk() 前：
+  记下 preGameData = gameData（深拷贝）
+  
+reloadFromDisk() 后：
+  diff = computeDiff(preGameData, newGameData)
+  aiChanges = { added, modified, deleted }
+  
+SceneGraph:
+  渲染时根据 aiChanges 给对应节点加角标
+```
+
+### 数据结构
+
+```ts
+interface AIDiff {
+  added: string[]        // 新 gameData 中有，旧 gameData 中没有的 scene ID
+  modified: string[]      // 相同 ID，JSON.stringify 不同的 scene ID
+  deleted: string[]       // 旧 gameData 中有，新 gameData 中没有的 scene ID
+  globalFields: string[]  // 变更的全局配置字段名，例如 ["title", "assetBase"]
+}
+```
+
+### diff 计算逻辑（editorStore.reloadFromDisk 内）
+
+```ts
+const { scenes: oldScenes, ...oldGlobal } = oldGameData
+const { scenes: newScenes, ...newGlobal } = newGameData
+const diff: AIDiff = { added: [], modified: [], deleted: [], globalFields: [] }
+
+for (const id of Object.keys(newScenes)) {
+  if (!oldScenes[id]) diff.added.push(id)
+  else if (JSON.stringify(oldScenes[id]) !== JSON.stringify(newScenes[id])) diff.modified.push(id)
+}
+for (const id of Object.keys(oldScenes)) {
+  if (!newScenes[id]) diff.deleted.push(id)
+}
+
+for (const key of Object.keys({ ...oldGlobal, ...newGlobal })) {
+  if (JSON.stringify(oldGlobal[key]) !== JSON.stringify(newGlobal[key])) {
+    diff.globalFields.push(key)
+  }
+}
+```
+
+同时检测全局配置变更（startScene、title 等），记录到 `globalFields`。
+
+### 角标视觉效果
+
+Vue Flow 自定义节点模板（SceneGraph.vue 已有 `CustomNode` 组件）：
+
+```
+  ┌──────────────┐
+  │   ● NEW      │  ← 绿色角标 (纯 CSS 色块)
+  │ scene_A      │
+  └──────────────┘
+
+  ┌──────────────┐
+  │   ● MOD      │  ← 橙色角标
+  │ scene_B      │
+  └──────────────┘
+```
+
+CSS 实现：在节点元素右上角添加绝对定位的 `<span class="diff-badge">`。
+
+### 全局配置变更标记
+
+当 `aiChanges.globalFields` 非空时，在 `NodeEditor` 的"全局配置"标题区展示：
+
+```
+┌─────────────────────────────┐
+│  全局配置  ● 已修改 3 字段   │  ← 橙色圆点 + 变更字段数
+│  ╭──────────────────╮       │
+│  │ title: "xxx"      │       │  ← 鼠标 hover 时弹出 tooltip
+│  │ startScene: "yyy" │       │    列出具体变更的字段名
+│  │ assetBase: "zzz"  │       │
+│  ╰──────────────────╯       │
+│  {                          │
+│   "title": "xxx",     ← 正常 JSON textarea 不变
+│   ...                       │
+└─────────────────────────────┘
+```
+
+**不变更项占位**：用逗号分隔字段名，如 `已修改 3 字段`；hover 列出所有字段名。
+
+**清除**：用户 blur JSON textarea 后标记消失（手工编辑即为最终确认）。
+
+### 标记清除时机
+
+| 条件 | 行为 |
+|------|------|
+| 用户手动编辑任意节点后 blur 保存 | 清除 `aiChanges`，所有标记消失 |
+| 用户手动编辑全局配置后 blur 保存 | 清除全局配置标记 |
+| AIPanel 点击"清除高亮"按钮 | 手动清除所有标记 |
+| 新一轮 AI 修改 | 覆盖旧 diff（新 diff 替换旧 diff） |
+
+### 涉及文件
+
+| 文件 | 改动 |
+|------|------|
+| `editor/stores/editorStore.ts` | 新增 `aiChanges` ref、diff 计算逻辑、标记清除 |
+| `editor/components/SceneGraph.vue` | watch `aiChanges`、自定义节点模板加角标 |
+| `editor/components/NodeEditor.vue` | 全局配置标题加变更提示 |
+
+---
+
+## 三、完整交互时序
+
+```
+用户输入需求 "添加一个新场景 scene_battle"
+     │
+     ▼
+AIPanel.send()
+  ① saveVersion("AI 修改前")              ← 快照
+  ② preGameData = clone gameData            ← 记下旧值
+  ③ sendAIRequest(buildMessage(msg), ...)
+     │
+     ▼
+opencode 读文件 → 新增 scene_battle → 写盘 → 回复 "已创建 scene_battle"
+     │
+     ▼
+AIPanel 收到 result
+  ④ 聊天显示 result
+  ⑤ store.reloadFromDisk()
+       ├─ fetch → 新 gameData
+        ├─ diff(oldGameData, newGameData) → aiChanges = { added: ["scene_battle"], modified: [], deleted: [], globalFields: [] }
+       ├─ gameData = newGameData
+       └─ selectedNodeId = null
+     │
+     ▼
+SceneGraph 检测到 aiChanges 非空
+  → 新增节点 scene_battle 渲染时显示绿色 "NEW" 角标
+  → 已有节点无角标
+     │
+     ▼
+用户手动编辑任一节点后 blur
+  → store.clearAIMarkers()
+  → 所有角标消失
+```
+
+---
+
+## 四、改动清单
+
+### editor/db/editorDB.ts（新建）
+
+| API | 说明 |
+|-----|------|
+| `initDB()` | 打开/创建 `editor_versions` 数据库 |
+| `putVersion(v)` | 存入版本快照 |
+| `getVersions(sourcePath)` | 获取某文件所有版本（按时间倒序，最多 20） |
+| `clearVersions(sourcePath)` | 清除某文件的版本（切换文件/删除旧版本时） |
+
+### editor/stores/editorStore.ts
+
+| 新增 | 说明 |
+|------|------|
+| `versions: Ref<EditorVersion[]>` | 当前文件的所有历史版本 |
+| `aiChanges: Ref<AIDiff>` | 上次 AI 修改的 diff 结果 |
+| `saveVersion(label)` | 深拷贝 gameData → 存 IndexedDB → 更新 versions |
+| `restoreVersion(idx)` | gameData = versions[idx].gameData → autoSave |
+| `reloadFromDisk()` 增强 | diff 计算 + 设置 aiChanges |
+| `clearAIMarkers()` | aiChanges = null |
+| `loadVersions()` | 加载当前 sourcePath 的版本列表 |
+
+### editor/components/SceneGraph.vue
+
+| 新增 | 说明 |
+|------|------|
+| `watch(aiChanges)` | 重新渲染时按 aiChanges 给节点加 badge |
+| CSS `.diff-badge` / `.diff-badge-added` / `.diff-badge-modified` / `.diff-badge-deleted` | 角标样式 |
+
+### editor/components/AIPanel.vue
+
+| 新增 | 说明 |
+|------|------|
+| 版本下拉 UI | `<select v-model="selectedVersion">` + 恢复按钮 |
+| `send()` 前调 `saveVersion("AI 修改前")` | 在 `loading = true` 前 |
+| "清除高亮" 按钮 | 调用 `store.clearAIMarkers()` |
+
+### editor/components/NodeEditor.vue
+
+| 新增 | 说明 |
+|------|------|
+| 全局配置标题加标记 | `全局配置 ● 已修改 N 字段` + hover tooltip 显示字段名，当 `aiChanges.globalFields` 非空 |
+| `onBlur()` 时调 `clearAIMarkers()` | 编辑后清除标记 |
+
+---
+
+## 五、非侵入性保证
+
+| 项 | 保障 |
+|----|------|
+| IndexedDB 故障容忍 | try/catch 包裹所有操作，失败不影响主流程 |
+| 版本存储增长 | 20 个上限 + 切换文件时清空旧文件的版本 |
+| SceneGraph 性能 | diff 比较仅用 `Object.keys` + `JSON.stringify`，百级节点 < 2ms |
+| 不影响手动编辑 | `clearAIMarkers()` 在 blur 时调用，角标不留存 |
+| 不影响 Code 模式 | 仅在 JSON 模式 `reloadFromDisk()` 时做 diff |
+| 不使用 emoji | CSS 纯色圆点 + 文字实现角标 |
+
+---
+
+## 六、测试用例
+
+### V1：版本自动保存
+| 步骤 | 预期 |
+|------|------|
+| 编辑器中加载 demo.json | 自动创建版本 "初始版本" |
+| 打开 AIPanel，JSON 模式发送"添加场景" | 自动创建版本 "AI 修改前" |
+| 打开版本下拉 | 显示两个版本 |
+
+### V2：版本恢复
+| 步骤 | 预期 |
+|------|------|
+| AI 修改后选择 "AI 修改前" 版本 | 点击恢复 |
+| 编辑器内容回到修改前 | SceneGraph + NodeEditor 刷新为旧内容 |
+
+### V3：修改标记
+| 步骤 | 预期 |
+|------|------|
+| AI 新增 scene_battle | SceneGraph 中该节点显示绿色 "NEW" 角标 |
+| AI 修改 scene_start | 该节点显示橙色 "MOD" 角标 |
+| AI 修改 title + startScene | NodeEditor 全局配置标题显示 "● 已修改 2 字段"，hover 列出 title/startScene |
+| 用户手动编辑任一节点后 blur | 所有角标消失 |
+| 用户手动编辑全局配置后 blur | 全局配置标记消失 |
+
+### V4：非侵入
+| 步骤 | 预期 |
+|------|------|
+| 不通过 AI 直接手动编辑 JSON | 不触发版本保存，不显示角标 |
+| 浏览器不支持 IndexedDB | 版本功能静默失效，不影响编辑 |
diff --git a/editor/components/AIPanel.vue b/editor/components/AIPanel.vue
index 890c1bf..168401c 100644
--- a/editor/components/AIPanel.vue
+++ b/editor/components/AIPanel.vue
@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { ref, nextTick } from 'vue'
+import { ref, nextTick, onMounted } from 'vue'
 import { useEditorStore } from '../stores/editorStore'
 import { sendAIRequest } from '../composables/useAI'
 
@@ -40,13 +40,19 @@ async function send() {
   messages.value.push({ role: 'user', content: userInput })
   loading.value = true
 
+  if (mode.value === 'json') {
+    await store.saveVersion('AI 修改前')
+  }
+
+  const oldGameData = mode.value === 'json' ? JSON.parse(JSON.stringify(store.gameData)) : undefined
+
   try {
     const { result, sessionId: newSid } = await sendAIRequest(fullMessage, mode.value, store.deepseekKey, store.aiSessionId || undefined)
     if (newSid) store.setAISessionId(newSid)
 
     if (mode.value === 'json') {
       messages.value.push({ role: 'assistant', content: result || '已完成' })
-      await store.reloadFromDisk()
+      await store.reloadFromDisk(oldGameData)
     } else {
       messages.value.push({ role: 'assistant', content: result || '已完成' })
     }
@@ -68,6 +74,10 @@ function newSession() {
   messages.value = []
   errorMsg.value = ''
 }
+
+onMounted(() => {
+  store.loadVersions()
+})
 </script>
 
 <template>
@@ -83,6 +93,16 @@ function newSession() {
       </div>
     </div>
 
+    <div v-if="store.versions.length > 0 || store.aiChanges" class="ai-toolbar">
+      <select v-if="store.versions.length > 0" class="ai-version-select" @change="store.restoreVersion(($event.target as HTMLSelectElement).selectedIndex)">
+        <option disabled selected>历史版本</option>
+        <option v-for="v in store.versions" :key="v.timestamp">
+          {{ new Date(v.timestamp).toLocaleString('zh-CN') }} {{ v.label }}
+        </option>
+      </select>
+      <button v-if="store.aiChanges" class="ai-clear-btn" @click="store.clearAIMarkers()">清除高亮</button>
+    </div>
+
     <div class="ai-chat" ref="chatRef">
       <div v-if="!store.deepseekKey" class="ai-key-setup">
         <span class="key-label">DeepSeek API Key</span>
@@ -289,4 +309,36 @@ function newSession() {
   font-size: 11px;
   color: #666;
 }
+
+.ai-toolbar {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 6px 16px;
+  border-bottom: 1px solid rgba(255,255,255,0.06);
+  flex-shrink: 0;
+}
+
+.ai-version-select {
+  flex: 1;
+  padding: 4px 8px;
+  font-size: 11px;
+  background: rgba(255,255,255,0.05);
+  border: 1px solid rgba(255,255,255,0.1);
+  border-radius: 3px;
+  color: #ccc;
+  outline: none;
+}
+
+.ai-clear-btn {
+  padding: 4px 10px;
+  font-size: 11px;
+  color: #ccc;
+  background: rgba(255,255,255,0.05);
+  border: 1px solid rgba(255,255,255,0.1);
+  border-radius: 3px;
+  cursor: pointer;
+  white-space: nowrap;
+}
+.ai-clear-btn:hover { color: #fff; border-color: rgba(255,255,255,0.2); }
 </style>
diff --git a/editor/components/NodeEditor.vue b/editor/components/NodeEditor.vue
index b3ef186..5f9ef24 100644
--- a/editor/components/NodeEditor.vue
+++ b/editor/components/NodeEditor.vue
@@ -17,6 +17,7 @@ const store = useEditorStore()
 const jsonText = ref('')
 const errorMsg = ref('')
 const saved = ref(false)
+const globalTooltip = ref('')
 
 watch(() => [props.scene, store.gameData] as const, () => {
   errorMsg.value = ''
@@ -32,6 +33,7 @@ watch(() => [props.scene, store.gameData] as const, () => {
 }, { immediate: true, deep: true })
 
 function onBlur() {
+  store.clearAIMarkers()
   errorMsg.value = ''
   try {
     const parsed = JSON.parse(jsonText.value)
@@ -54,7 +56,7 @@ function onBlur() {
 <template>
   <div class="node-editor" v-if="scene || jsonText">
     <div class="editor-header">
-      <h3>{{ scene ? scene.id : '全局配置' }}</h3>
+      <h3>{{ scene ? scene.id : '全局配置' }}<span v-if="!scene && store.aiChanges?.globalFields?.length" class="global-diff-tag" :title="store.aiChanges.globalFields.join(', ')">● 已修改 {{ store.aiChanges.globalFields.length }} 字段</span></h3>
       <div class="header-actions">
         <span v-if="saved" class="saved-hint">已保存</span>
         <span v-if="errorMsg" class="error-hint">JSON 错误: {{ errorMsg }}</span>
@@ -165,4 +167,17 @@ function onBlur() {
 .json-area.error {
   border-left: 3px solid #e74c3c;
 }
+
+.global-diff-tag {
+  display: inline-block;
+  margin-left: 10px;
+  padding: 1px 8px;
+  font-size: 11px;
+  font-weight: 400;
+  color: #ffe0b2;
+  background: rgba(230, 81, 0, 0.15);
+  border: 1px solid rgba(230, 81, 0, 0.3);
+  border-radius: 3px;
+  cursor: default;
+}
 </style>
diff --git a/editor/components/SceneGraph.vue b/editor/components/SceneGraph.vue
index df23bf6..c34db1e 100644
--- a/editor/components/SceneGraph.vue
+++ b/editor/components/SceneGraph.vue
@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import { ref, watch, nextTick } from 'vue'
-import { VueFlow, useVueFlow, SmoothStepEdge } from '@vue-flow/core'
+import { VueFlow, useVueFlow, SmoothStepEdge, Handle, Position } from '@vue-flow/core'
 import { Background } from '@vue-flow/background'
 import { Controls } from '@vue-flow/controls'
 import '@vue-flow/core/dist/style.css'
@@ -8,6 +8,7 @@ import '@vue-flow/controls/dist/style.css'
 import '@vue-flow/core/dist/theme-default.css'
 import type { Connection } from '@vue-flow/core'
 import { computePositions, savePosition } from '../composables/useLayout'
+import { useEditorStore } from '../stores/editorStore'
 
 const props = defineProps<{
   sceneNodes: { id: string; label: string }[]
@@ -23,6 +24,8 @@ const emit = defineEmits<{
   clearSelection: []
 }>()
 
+const store = useEditorStore()
+
 const nodes = ref<any[]>([])
 const edges = ref<any[]>([])
 const { onNodeClick, onConnect, onNodeContextMenu, onNodeDragStop, onPaneClick, fitView } = useVueFlow()
@@ -33,13 +36,23 @@ const ctxMenuNodeId = ref('')
 
 function makeNodes() {
   const positions = computePositions(props.sceneNodes, props.sceneEdges, props.startScene)
+  const changes = store.aiChanges
   return props.sceneNodes.map((n) => {
     const pos = positions.get(n.id) ?? { x: 0, y: 0 }
+    let badge = ''
+    if (changes) {
+      if (changes.added.includes(n.id)) badge = 'NEW'
+      else if (changes.modified.includes(n.id)) badge = 'MOD'
+      else if (changes.deleted.includes(n.id)) badge = 'DEL'
+    }
     return {
       id: n.id,
       type: 'default',
       position: pos,
-      data: { label: n.id === props.startScene ? `\u25b6 ${n.label}` : n.label },
+      data: {
+        label: n.id === props.startScene ? `\u25b6 ${n.label}` : n.label,
+        badge,
+      },
       style: n.id === props.startScene
         ? { background: '#1b5e20', color: '#fff', borderColor: '#388e3c' }
         : n.id === props.selectedNodeId
@@ -99,7 +112,7 @@ function inlineRebuild() {
 }
 
 watch(
-  () => [props.sceneNodes, props.sceneEdges, props.startScene, props.selectedNodeId] as const,
+  () => [props.sceneNodes, props.sceneEdges, props.startScene, props.selectedNodeId, store.aiChanges] as const,
   () => {
     const nc = props.sceneNodes.length
     const ec = props.sceneEdges.length
@@ -152,6 +165,16 @@ onConnect((conn: Connection) => {
       :min-zoom="0.2"
       :max-zoom="2"
     >
+      <template #node-default="nodeProps">
+        <div class="custom-node">
+          <Handle type="target" :position="Position.Left" />
+          <div class="custom-node-label">{{ nodeProps.data.label }}</div>
+          <span v-if="nodeProps.data.badge" class="diff-badge" :class="`diff-badge-${nodeProps.data.badge}`">
+            {{ nodeProps.data.badge }}
+          </span>
+          <Handle type="source" :position="Position.Right" />
+        </div>
+      </template>
       <Background :gap="20" />
       <Controls />
     </VueFlow>
@@ -207,4 +230,44 @@ onConnect((conn: Connection) => {
   background: rgba(100,200,255,0.12);
   color: #fff;
 }
+
+.custom-node {
+  position: relative;
+  padding: 8px 30px 8px 12px;
+  min-width: 120px;
+  font-size: 12px;
+}
+
+.custom-node-label {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.diff-badge {
+  position: absolute;
+  top: 2px;
+  right: 4px;
+  padding: 1px 5px;
+  font-size: 9px;
+  font-weight: 600;
+  border-radius: 2px;
+  line-height: 1.4;
+}
+
+.diff-badge-NEW {
+  background: #2e7d32;
+  color: #c8e6c9;
+}
+
+.diff-badge-MOD {
+  background: #e65100;
+  color: #ffe0b2;
+}
+
+.diff-badge-DEL {
+  background: #c62828;
+  color: #ffcdd2;
+  text-decoration: line-through;
+}
 </style>
diff --git a/editor/db/editorDB.ts b/editor/db/editorDB.ts
new file mode 100644
index 0000000..93c75b5
--- /dev/null
+++ b/editor/db/editorDB.ts
@@ -0,0 +1,57 @@
+import Dexie, { type Table } from 'dexie'
+import type { GameData } from '@engine/types'
+
+export interface VersionRecord {
+  id?: number
+  sourcePath: string
+  timestamp: number
+  label: string
+  gameData: GameData
+}
+
+class EditorDB extends Dexie {
+  versions!: Table<VersionRecord, number>
+
+  constructor() {
+    super('EditorVersions')
+    this.version(1).stores({
+      versions: '++id, sourcePath, timestamp',
+    })
+  }
+}
+
+const db = new EditorDB()
+
+export async function putVersion(record: VersionRecord): Promise<void> {
+  try {
+    await db.versions.add(record)
+    const all = await db.versions
+      .where('sourcePath')
+      .equals(record.sourcePath)
+      .reverse()
+      .sortBy('timestamp')
+    if (all.length > 20) {
+      const toDelete = all.slice(20)
+      await db.versions.bulkDelete(toDelete.map((v) => v.id!))
+    }
+  } catch {}
+}
+
+export async function getVersions(sourcePath: string): Promise<VersionRecord[]> {
+  try {
+    return await db.versions
+      .where('sourcePath')
+      .equals(sourcePath)
+      .reverse()
+      .sortBy('timestamp')
+  } catch {
+    return []
+  }
+}
+
+export async function clearVersions(sourcePath: string): Promise<void> {
+  try {
+    const records = await db.versions.where('sourcePath').equals(sourcePath).toArray()
+    await db.versions.bulkDelete(records.map((v) => v.id!))
+  } catch {}
+}
diff --git a/editor/stores/editorStore.ts b/editor/stores/editorStore.ts
index eb4792e..02b207a 100644
--- a/editor/stores/editorStore.ts
+++ b/editor/stores/editorStore.ts
@@ -1,6 +1,22 @@
 import { defineStore } from 'pinia'
 import { shallowRef, ref, computed, triggerRef } from 'vue'
 import type { GameData, SceneNode, Choice } from '@engine/types'
+import { putVersion, getVersions } from '../db/editorDB'
+
+export interface AIDiff {
+  added: string[]
+  modified: string[]
+  deleted: string[]
+  globalFields: string[]
+}
+
+interface EditorVersion {
+  id?: number
+  sourcePath: string
+  timestamp: number
+  label: string
+  gameData: GameData
+}
 
 export const useEditorStore = defineStore('editor', () => {
   const gameData = shallowRef<GameData>({ scenes: {}, startScene: '', variables: {} })
@@ -11,6 +27,8 @@ export const useEditorStore = defineStore('editor', () => {
   const deepseekKey = ref(localStorage.getItem('deepseek_key') || '')
   const showAIPanel = ref(false)
   const aiSessionId = ref('')
+  const aiChanges = ref<AIDiff | null>(null)
+  const versions = ref<EditorVersion[]>([])
 
   const selectedScene = computed(() => {
     if (!selectedNodeId.value) return null
@@ -151,11 +169,64 @@ export const useEditorStore = defineStore('editor', () => {
     } catch { /* dev server not running */ }
   }
 
-  async function reloadFromDisk() {
+  async function saveVersion(label: string) {
+    try {
+      await putVersion({
+        sourcePath: sourcePath.value,
+        timestamp: Date.now(),
+        label,
+        gameData: JSON.parse(JSON.stringify(gameData.value)),
+      })
+      await loadVersions()
+    } catch {}
+  }
+
+  async function restoreVersion(idx: number) {
+    const v = versions.value[idx]
+    if (!v) return
+    gameData.value = v.gameData
+    startSceneId.value = v.gameData.startScene || ''
+    selectedNodeId.value = null
+    aiChanges.value = null
+    dirty.value = false
+    autoSave()
+  }
+
+  async function loadVersions() {
+    try {
+      versions.value = await getVersions(sourcePath.value)
+    } catch {
+      versions.value = []
+    }
+  }
+
+  function clearAIMarkers() {
+    aiChanges.value = null
+  }
+
+  async function reloadFromDisk(oldGameData?: GameData) {
     try {
       const resp = await fetch(sourcePath.value)
-      const data = await resp.json()
-      gameData.value = data
+      const newData = await resp.json()
+      if (oldGameData) {
+        const { scenes: newScenes, ...newGlobal } = newData
+        const { scenes: oldScenes, ...oldGlobal } = oldGameData
+        const diff: AIDiff = { added: [], modified: [], deleted: [], globalFields: [] }
+        for (const id of Object.keys(newScenes)) {
+          if (!oldScenes[id]) diff.added.push(id)
+          else if (JSON.stringify(oldScenes[id]) !== JSON.stringify(newScenes[id])) diff.modified.push(id)
+        }
+        for (const id of Object.keys(oldScenes)) {
+          if (!newScenes[id]) diff.deleted.push(id)
+        }
+        for (const key of Object.keys({ ...(oldGlobal as any), ...(newGlobal as any) })) {
+          if (JSON.stringify((oldGlobal as any)[key]) !== JSON.stringify((newGlobal as any)[key])) {
+            diff.globalFields.push(key)
+          }
+        }
+        aiChanges.value = diff
+      }
+      gameData.value = newData
       selectedNodeId.value = null
       clearAISession()
     } catch { /* failed to reload */ }
@@ -163,9 +234,10 @@ export const useEditorStore = defineStore('editor', () => {
 
   return {
     gameData, selectedNodeId, selectedScene, startSceneId, dirty, sourcePath,
-    deepseekKey, showAIPanel, aiSessionId,
+    deepseekKey, showAIPanel, aiSessionId, aiChanges, versions,
     markDirty, loadJSON, exportJSON, addScene, deleteScene,
     updateScene, addChoice, updateChoice, deleteChoice, generateId,
     setSourcePath, setDeepseekKey, setAISessionId, clearAISession, autoSave, reloadFromDisk,
+    saveVersion, restoreVersion, loadVersions, clearAIMarkers,
   }
 })
diff --git a/public/scenes/demo.json b/public/scenes/demo.json
index 1848837..4b50177 100644
--- a/public/scenes/demo.json
+++ b/public/scenes/demo.json
@@ -127,6 +127,7 @@
   "scenes": {
     "intro": {
       "id": "intro",
+      "nextScene": "investigation_site",
       "videoUrl": "intro/intro.mp4",
       "streamingUrl": {
         "超清 (1080P)": "intro/1080p/index.m3u8",