diff --git a/web/src/data/promotionVideos.js b/web/src/data/promotionVideos.js
index aa9bfc8..537f0aa 100644
--- a/web/src/data/promotionVideos.js
+++ b/web/src/data/promotionVideos.js
@@ -44,16 +44,79 @@ export const PROMOTION_VIDEOS_BASE = [
   }
 ]
 
-/** @param {string} siteId 空串时走本地/静态 /promotion/… */
-export function buildPromotionVideos(siteId) {
+/**
+ * 检测同域静态 /promotion/ 文件是否可访问（优先 HEAD，405 时用 Range GET）
+ * @param {string} url
+ * @returns {Promise<boolean>}
+ */
+export async function promotionStaticUrlExists(url) {
+  try {
+    const head = await fetch(url, {
+      method: 'HEAD',
+      mode: 'same-origin',
+      credentials: 'same-origin',
+      cache: 'default'
+    })
+    if (head.ok) return true
+    if (head.status === 405) {
+      const r = await fetch(url, {
+        method: 'GET',
+        headers: { Range: 'bytes=0-0' },
+        mode: 'same-origin',
+        credentials: 'same-origin',
+        cache: 'default'
+      })
+      return r.ok || r.status === 206
+    }
+    return false
+  } catch {
+    return false
+  }
+}
+
+/**
+ * 有静态则静态，否则（需 siteId）走 promotion-media API
+ * @param {string} siteId
+ * @param {string} relPath promotion 下相对路径，如 social/xxx.mov
+ */
+export async function pickPromotionAssetUrl(siteId, relPath) {
+  const staticUrl = promotionUrl(relPath)
+  const hasStatic = await promotionStaticUrlExists(staticUrl)
+  if (hasStatic) return staticUrl
+  if (siteId) return promotionMediaApiUrl(siteId, relPath)
+  return staticUrl
+}
+
+/**
+ * 同步列表：全部静态 URL（首屏占位、无 siteId 时与异步结果一致场景）
+ * @param {string} [_siteId] 保留兼容，当前忽略
+ */
+export function buildPromotionVideos(_siteId) {
   return PROMOTION_VIDEOS_BASE.map((v) => ({
     id: v.id,
     title: v.title,
     desc: v.desc,
-    cover: promotionMediaApiUrl(siteId, v.relCover),
-    src: promotionMediaApiUrl(siteId, v.relVideo)
+    cover: promotionUrl(v.relCover),
+    src: promotionUrl(v.relVideo)
   }))
 }
 
-/** @deprecated 请用 buildPromotionVideos(siteId)；保留兼容旧引用 */
-export const PROMOTION_VIDEOS = buildPromotionVideos('')
+/**
+ * 静态优先：存在 /promotion/... 则用静态，否则用 uploads API（需 siteId）
+ * @param {string} siteId
+ */
+export async function buildPromotionVideosAsync(siteId) {
+  const id = siteId || ''
+  return Promise.all(
+    PROMOTION_VIDEOS_BASE.map(async (v) => {
+      const [cover, src] = await Promise.all([
+        pickPromotionAssetUrl(id, v.relCover),
+        pickPromotionAssetUrl(id, v.relVideo)
+      ])
+      return { id: v.id, title: v.title, desc: v.desc, cover, src }
+    })
+  )
+}
+
+/** @deprecated 请用 buildPromotionVideos() 或 buildPromotionVideosAsync */
+export const PROMOTION_VIDEOS = buildPromotionVideos()
diff --git a/web/src/utils/promotionAssets.js b/web/src/utils/promotionAssets.js
index 4db7269..b586e47 100644
--- a/web/src/utils/promotionAssets.js
+++ b/web/src/utils/promotionAssets.js
@@ -1,8 +1,8 @@
 import { apiBase } from '../config'
 
 /**
- * 推广素材根路径。开发时由 Vite 插件映射到 web/promotion；
- * 生产环境视频默认走后台上传：`/api/web/sites/{siteId}/promotion-media/...`（见 buildPromotionVideos）。
+ * 推广素材根路径。开发时由 Vite 映射到 web/promotion；
+ * 首页产品视频见 `buildPromotionVideosAsync`：同域静态存在则 `/promotion/...`，否则 `promotionMediaApiUrl`。
  */
 export function promotionUrl(relativePath) {
   const parts = String(relativePath).split('/').filter(Boolean)
diff --git a/web/src/views/Home.vue b/web/src/views/Home.vue
index 292e70a..6db8f31 100644
--- a/web/src/views/Home.vue
+++ b/web/src/views/Home.vue
@@ -312,7 +312,7 @@
 import { ref, reactive, computed, watch, onMounted, onUnmounted, nextTick } from 'vue'
 import { apiBase } from '../config'
 import BlockRenderer from '../components/blocks/BlockRenderer.vue'
-import { buildPromotionVideos } from '../data/promotionVideos'
+import { buildPromotionVideos, buildPromotionVideosAsync } from '../data/promotionVideos'
 import { PROMOTION_SOCIAL_FOLLOW } from '../data/promotionSocial'
 import { getCachedWebSiteId, fetchWebRoutes } from '../api/webPages'
 
@@ -322,9 +322,18 @@ const starsEl = ref(null)
 let cometTimer = null
 const scrollY = ref(0)
 const openFaq = ref(0)
-/** 官网 site_id（bootstrap 已拉路由时此处已有值；为空则产品视频走本地 /promotion） */
+/** 官网 site_id（bootstrap 已拉路由时此处已有值；产品视频：静态优先，否则 promotion-media API） */
 const webSiteId = ref(getCachedWebSiteId() || '')
-const promoVideos = computed(() => buildPromotionVideos(webSiteId.value))
+const promoVideos = ref(buildPromotionVideos(webSiteId.value))
+async function refreshPromoVideos() {
+  const id = webSiteId.value || ''
+  try {
+    promoVideos.value = await buildPromotionVideosAsync(id)
+  } catch {
+    promoVideos.value = buildPromotionVideos(id)
+  }
+}
+watch(webSiteId, refreshPromoVideos, { immediate: true })
 const activeVideo = ref(null)
 watch(
   promoVideos,
@@ -333,7 +342,7 @@ watch(
     const cur = activeVideo.value
     if (!cur || !list.some((v) => v.id === cur.id)) activeVideo.value = list[0]
   },
-  { immediate: true }
+  { immediate: true, deep: true }
 )
 const videoModalOpen = ref(false)
 const modalVideoSrc = ref('')