diff --git a/FileShare-Services/Endpoints/AppEndpoints.cs b/FileShare-Services/Endpoints/AppEndpoints.cs
index 0726cf3..782539b 100644
--- a/FileShare-Services/Endpoints/AppEndpoints.cs
+++ b/FileShare-Services/Endpoints/AppEndpoints.cs
@@ -82,6 +82,10 @@ namespace FileShare_Services.Endpoints
                     .WithOpenApi("FileLibrary", "保存文件播放进度。")
                     .WithName("SaveFileProgress");
 
+                endpoints.MapPost<IFileLibraryEndpointService, DeleteFileRequest>("api/files/delete", (service, request, _) => service.DeleteFileAsync(request))
+                    .WithOpenApi("FileLibrary", "永久删除文件（物理文件+数据库记录）。")
+                    .WithName("DeleteFile");
+
                 endpoints.MapGet<IFileLibraryEndpointService, FileQueryRequest>("api/files/detail", (service, request, _) => service.GetFileAsync(request))
                     .WithOpenApi("FileLibrary", "查询文件详情。")
                     .WithName("GetFileDetail");
diff --git a/FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs b/FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs
index e71150c..b3073af 100644
--- a/FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs
+++ b/FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs
@@ -34,6 +34,12 @@ namespace FileShare_Services.Services.FileLibrary
     public sealed record DeleteLibraryRootRequest(
         [property: JsonPropertyName("id")] int Id);
 
+    /// <summary>
+    /// 永久删除文件的请求。
+    /// </summary>
+    public sealed record DeleteFileRequest(
+        [property: JsonPropertyName("id")] int Id);
+
     /// <summary>
     /// 查询服务器子目录的请求。
     /// </summary>
diff --git a/FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs b/FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs
index 4bb5c60..d3e6995 100644
--- a/FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs
+++ b/FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs
@@ -113,6 +113,14 @@ namespace FileShare_Services.Services.FileLibrary
             return ResponseHelper.Succeed();
         }
 
+        /// <inheritdoc />
+        public async Task<IApiResponse> DeleteFileAsync(DeleteFileRequest request)
+        {
+            ValidateFileId(request.Id);
+            await fileLibrary.DeleteFileAsync(request.Id);
+            return ResponseHelper.Succeed("文件已永久删除。");
+        }
+
         /// <summary>
         /// 验证文件 ID 是否有效，无效时抛出 <see cref="ArgumentException"/>。
         /// </summary>
diff --git a/FileShare-Services/Services/FileLibrary/FileLibraryService.cs b/FileShare-Services/Services/FileLibrary/FileLibraryService.cs
index 728e1d1..cb43f03 100644
--- a/FileShare-Services/Services/FileLibrary/FileLibraryService.cs
+++ b/FileShare-Services/Services/FileLibrary/FileLibraryService.cs
@@ -545,6 +545,54 @@ namespace FileShare_Services.Services.FileLibrary
             }
         }
 
+        /// <inheritdoc />
+        public async Task DeleteFileAsync(int id, CancellationToken cancellationToken = default)
+        {
+            var record = await db.ManagedFileRecords
+                .Include(f => f.Thumbnail)
+                .FirstOrDefaultAsync(f => f.Id == id, cancellationToken);
+
+            if (record is null)
+            {
+                return;
+            }
+
+            // 删除物理文件
+            try
+            {
+                if (File.Exists(record.AbsolutePath))
+                {
+                    File.Delete(record.AbsolutePath);
+                }
+            }
+            catch (Exception ex)
+            {
+                Serilog.Log.Warning(ex, "删除物理文件失败 FilePath={FilePath}", record.AbsolutePath);
+            }
+
+            // 删除缩略图文件
+            if (record.Thumbnail is not null)
+            {
+                try
+                {
+                    var thumbnailPath = thumbnailService.GetAbsolutePath(record.Thumbnail.RelativePath);
+                    if (File.Exists(thumbnailPath))
+                    {
+                        File.Delete(thumbnailPath);
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Serilog.Log.Warning(ex, "删除缩略图文件失败 ThumbnailId={ThumbnailId}", record.ThumbnailId);
+                }
+
+                db.ManagedThumbnailMaps.Remove(record.Thumbnail);
+            }
+
+            db.ManagedFileRecords.Remove(record);
+            await db.SaveChangesAsync(cancellationToken);
+        }
+
         /// <summary>
         /// 深度优先遍历目录树，枚举所有被 <see cref="MediaFileTypes"/> 支持的媒体文件路径。
         /// 遇到无权限的目录时跳过该分支继续遍历。
diff --git a/FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs b/FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs
index df68761..c96b327 100644
--- a/FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs
+++ b/FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs
@@ -105,5 +105,12 @@ namespace FileShare_Services.Services.FileLibrary
         /// <param name="request">包含文件 ID 和播放位置的请求。</param>
         /// <returns>API 响应。</returns>
         Task<IApiResponse> SaveFileProgressAsync(SaveFileProgressRequest request);
+
+        /// <summary>
+        /// 永久删除指定文件。
+        /// </summary>
+        /// <param name="request">包含文件 ID 的请求。</param>
+        /// <returns>API 响应。</returns>
+        Task<IApiResponse> DeleteFileAsync(DeleteFileRequest request);
     }
 }
diff --git a/FileShare-Services/Services/FileLibrary/IFileLibraryService.cs b/FileShare-Services/Services/FileLibrary/IFileLibraryService.cs
index 84688d6..691786c 100644
--- a/FileShare-Services/Services/FileLibrary/IFileLibraryService.cs
+++ b/FileShare-Services/Services/FileLibrary/IFileLibraryService.cs
@@ -121,5 +121,12 @@ namespace FileShare_Services.Services.FileLibrary
         /// <param name="position">播放位置（秒）。</param>
         /// <param name="cancellationToken">取消令牌。</param>
         Task SaveFileProgressAsync(int id, double position, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// 永久删除指定文件，同时删除物理文件和缩略图。
+        /// </summary>
+        /// <param name="id">文件记录 ID。</param>
+        /// <param name="cancellationToken">取消令牌。</param>
+        Task DeleteFileAsync(int id, CancellationToken cancellationToken = default);
     }
 }
diff --git a/FileShare-Web-VUE/src/api/index.ts b/FileShare-Web-VUE/src/api/index.ts
index 56b872d..57887f7 100644
--- a/FileShare-Web-VUE/src/api/index.ts
+++ b/FileShare-Web-VUE/src/api/index.ts
@@ -114,5 +114,7 @@ export const api = {
     request('files/played', { method: 'POST', body: { id } }),
   saveFileProgress: (id: number, position: number) =>
     request('files/progress', { method: 'POST', body: { id, position } }),
+  deleteFile: (id: number) =>
+    request('files/delete', { method: 'POST', body: { id } }),
   qrCode: () => request<{ url: string; qrCodeBase64: string }>('qrcode'),
 }
diff --git a/FileShare-Web-VUE/src/components/ClientPage.vue b/FileShare-Web-VUE/src/components/ClientPage.vue
index 133dc81..4d64568 100644
--- a/FileShare-Web-VUE/src/components/ClientPage.vue
+++ b/FileShare-Web-VUE/src/components/ClientPage.vue
@@ -272,6 +272,24 @@ function exitSearch() {
   searchTotalPages.value = 0
 }
 
+async function deleteFile(file: FileRecordDto) {
+  if (!window.confirm(`确定要永久删除 "${file.fileName}" 吗？\n\n删除后无法恢复！`)) {
+    return
+  }
+  try {
+    await api.deleteFile(file.id)
+    await browseDirectory()
+    if (isSearching.value) {
+      await doSearch(searchPage.value)
+    }
+    if (selectedFile.value?.id === file.id) {
+      selectedFile.value = null
+    }
+  } catch (error) {
+    setError(error)
+  }
+}
+
 function updatePlaybackPosition(id: number, position: number) {
   if (selectedFile.value?.id === id) {
     selectedFile.value.playbackPosition = position
@@ -463,7 +481,7 @@ onBeforeUnmount(() => {
       <p v-else-if="searchResults.length === 0" class="empty-state">无匹配文件</p>
       <div v-else-if="viewMode === 'grid'" class="file-grid">
         <template v-for="file in searchResults" :key="file.id">
-          <FileCard :file="file" show-created-time @select="selectSearchFile" />
+          <FileCard :file="file" show-created-time @select="selectSearchFile" @delete="deleteFile" />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
           :ref="setMediaPlayer"
@@ -488,7 +506,7 @@ onBeforeUnmount(() => {
       </div>
       <div v-else class="file-list">
         <template v-for="file in searchResults" :key="file.id">
-          <FileListItem :file="file" show-created-time @select="selectSearchFile" />
+          <FileListItem :file="file" show-created-time @select="selectSearchFile" @delete="deleteFile" />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
           :ref="setMediaPlayer"
@@ -531,7 +549,7 @@ onBeforeUnmount(() => {
       </p>
       <div v-else-if="viewMode === 'grid'" class="file-grid">
         <template v-for="file in recentFiles" :key="file.id">
-          <FileCard :file="file" :selected="selectedFile?.id === file.id" @select="selectFile" />
+          <FileCard :file="file" :selected="selectedFile?.id === file.id" @select="selectFile" @delete="deleteFile" />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
           :ref="setMediaPlayer"
@@ -561,6 +579,7 @@ onBeforeUnmount(() => {
             :selected="selectedFile?.id === file.id"
             :show-last-played="activeTab === 'recent-played'"
             @select="selectFile"
+            @delete="deleteFile"
           />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
@@ -630,6 +649,7 @@ onBeforeUnmount(() => {
                 :selected="selectedFile?.id === file.id"
                 show-created-time
                 @select="selectFile"
+                @delete="deleteFile"
               />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
@@ -661,6 +681,7 @@ onBeforeUnmount(() => {
                 :selected="selectedFile?.id === file.id"
                 show-created-time
                 @select="selectFile"
+                @delete="deleteFile"
               />
 <SelectedMediaPlayerHost
           v-if="selectedFile?.id === file.id"
diff --git a/FileShare-Web-VUE/src/components/client/FileCard.vue b/FileShare-Web-VUE/src/components/client/FileCard.vue
index 988d13a..2afd156 100644
--- a/FileShare-Web-VUE/src/components/client/FileCard.vue
+++ b/FileShare-Web-VUE/src/components/client/FileCard.vue
@@ -10,6 +10,7 @@ defineProps<{
 
 defineEmits<{
   select: [file: FileRecordDto]
+  delete: [file: FileRecordDto]
 }>()
 </script>
 
@@ -20,6 +21,7 @@ defineEmits<{
     type="button"
     @click="$emit('select', file)"
   >
+    <span class="delete-btn" @click.stop="$emit('delete', file)" title="永久删除">删除</span>
     <img
       v-if="file.thumbnailUrl"
       :src="api.thumbnailUrl(file.thumbnailUrl)"
@@ -38,3 +40,26 @@ defineEmits<{
     </div>
   </button>
 </template>
+
+<style scoped>
+.delete-btn {
+  position: absolute;
+  top: 4px;
+  right: 4px;
+  padding: 2px 8px;
+  border-radius: 4px;
+  background: rgba(0, 0, 0, 0.6);
+  color: #fff;
+  font-size: 12px;
+  line-height: 18px;
+  cursor: pointer;
+  opacity: 0;
+  transition: opacity 0.15s;
+}
+.file-card:hover .delete-btn {
+  opacity: 1;
+}
+.delete-btn:hover {
+  background: #e53e3e;
+}
+</style>
diff --git a/FileShare-Web-VUE/src/components/client/FileListItem.vue b/FileShare-Web-VUE/src/components/client/FileListItem.vue
index 01cb6a5..c4da866 100644
--- a/FileShare-Web-VUE/src/components/client/FileListItem.vue
+++ b/FileShare-Web-VUE/src/components/client/FileListItem.vue
@@ -11,6 +11,7 @@ defineProps<{
 
 defineEmits<{
   select: [file: FileRecordDto]
+  delete: [file: FileRecordDto]
 }>()
 </script>
 
@@ -38,5 +39,29 @@ defineEmits<{
       </small>
       <small v-if="showCreatedTime && formatCreatedTime(file)">{{ formatCreatedTime(file) }}</small>
     </span>
+    <span class="delete-btn" @click.stop="$emit('delete', file)" title="永久删除">删除</span>
   </button>
 </template>
+
+<style scoped>
+.delete-btn {
+  margin-left: auto;
+  padding: 2px 10px;
+  border-radius: 4px;
+  background: rgba(0, 0, 0, 0.06);
+  color: #999;
+  font-size: 12px;
+  line-height: 20px;
+  cursor: pointer;
+  flex-shrink: 0;
+  opacity: 0;
+  transition: opacity 0.15s;
+}
+.mobile-file:hover .delete-btn {
+  opacity: 1;
+}
+.delete-btn:hover {
+  background: #e53e3e;
+  color: #fff;
+}
+</style>
diff --git a/docs/compose/plans/2026-07-09-file-delete.md b/docs/compose/plans/2026-07-09-file-delete.md
new file mode 100644
index 0000000..169278d
--- /dev/null
+++ b/docs/compose/plans/2026-07-09-file-delete.md
@@ -0,0 +1,431 @@
+# File Delete Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use compose:subagent (recommended) or compose:execute to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Add a permanent file delete API endpoint and frontend delete button with confirmation dialog.
+
+**Architecture:** Backend adds `POST api/files/delete` that deletes physical file + thumbnail + DB record. Frontend adds delete button to FileCard and FileListItem, with `window.confirm()` guard.
+
+**Tech Stack:** ASP.NET Core 10, EF Core 10, Vue 3.5, TypeScript 6
+
+## Global Constraints
+
+- Do not edit `FileShare-EFCore/Migrations/**` — schema changes require user to run migration scripts
+- All endpoints use POST (project convention)
+- Frontend response interceptor auto-unwraps `{ success, data }` envelope
+- Follow existing code patterns (sealed record DTOs, `ResponseHelper`, `defineProps`/`defineEmits`)
+
+---
+
+## File Map
+
+| File | Action | Purpose |
+|------|--------|---------|
+| `FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs` | Modify | Add `DeleteFileRequest` DTO |
+| `FileShare-Services/Services/FileLibrary/IFileLibraryService.cs` | Modify | Add `DeleteFileAsync` method |
+| `FileShare-Services/Services/FileLibrary/FileLibraryService.cs` | Modify | Implement delete logic |
+| `FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs` | Modify | Add `DeleteFileAsync` endpoint method |
+| `FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs` | Modify | Implement endpoint adapter |
+| `FileShare-Services/Endpoints/AppEndpoints.cs` | Modify | Register route |
+| `FileShare-Web-VUE/src/api/index.ts` | Modify | Add `deleteFile` API method |
+| `FileShare-Web-VUE/src/components/client/FileCard.vue` | Modify | Add delete button |
+| `FileShare-Web-VUE/src/components/client/FileListItem.vue` | Modify | Add delete button |
+| `FileShare-Web-VUE/src/components/ClientPage.vue` | Modify | Handle delete event |
+
+---
+
+## Task 1: Backend — Contract, Service Interface, Service Implementation
+
+**Covers:** S2 (backend delete logic)
+
+**Files:**
+- Modify: `FileShare-Services/Services/FileLibrary/FileLibraryContracts.cs:35`
+- Modify: `FileShare-Services/Services/FileLibrary/IFileLibraryService.cs:123`
+- Modify: `FileShare-Services/Services/FileLibrary/FileLibraryService.cs:546`
+
+- [ ] **Step 1: Add DeleteFileRequest to FileLibraryContracts.cs**
+
+After line 35 (the `DeleteLibraryRootRequest` record), add:
+
+```csharp
+    /// <summary>
+    /// 永久删除文件的请求。
+    /// </summary>
+    public sealed record DeleteFileRequest(
+        [property: JsonPropertyName("id")] int Id);
+```
+
+- [ ] **Step 2: Add DeleteFileAsync to IFileLibraryService.cs**
+
+After line 123 (`SaveFileProgressAsync`), add:
+
+```csharp
+        /// <summary>
+        /// 永久删除指定文件，同时删除物理文件和缩略图。
+        /// </summary>
+        /// <param name="id">文件记录 ID。</param>
+        /// <param name="cancellationToken">取消令牌。</param>
+        Task DeleteFileAsync(int id, CancellationToken cancellationToken = default);
+```
+
+- [ ] **Step 3: Implement DeleteFileAsync in FileLibraryService.cs**
+
+After line 546 (end of `SaveFileProgressAsync`), add:
+
+```csharp
+        /// <inheritdoc />
+        public async Task DeleteFileAsync(int id, CancellationToken cancellationToken = default)
+        {
+            var record = await db.ManagedFileRecords
+                .Include(f => f.Thumbnail)
+                .FirstOrDefaultAsync(f => f.Id == id, cancellationToken);
+
+            if (record is null)
+            {
+                return;
+            }
+
+            // 删除物理文件
+            try
+            {
+                if (File.Exists(record.AbsolutePath))
+                {
+                    File.Delete(record.AbsolutePath);
+                }
+            }
+            catch (Exception ex)
+            {
+                Serilog.Log.Warning(ex, "删除物理文件失败 FilePath={FilePath}", record.AbsolutePath);
+            }
+
+            // 删除缩略图文件
+            if (record.Thumbnail is not null)
+            {
+                try
+                {
+                    var thumbnailPath = thumbnailService.GetAbsolutePath(record.Thumbnail.RelativePath);
+                    if (File.Exists(thumbnailPath))
+                    {
+                        File.Delete(thumbnailPath);
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Serilog.Log.Warning(ex, "删除缩略图文件失败 ThumbnailId={ThumbnailId}", record.ThumbnailId);
+                }
+
+                db.ManagedThumbnailMaps.Remove(record.Thumbnail);
+            }
+
+            db.ManagedFileRecords.Remove(record);
+            await db.SaveChangesAsync(cancellationToken);
+        }
+```
+
+---
+
+## Task 2: Backend — Endpoint Service + Route Registration
+
+**Covers:** S2 (endpoint and routing)
+
+**Files:**
+- Modify: `FileShare-Services/Services/FileLibrary/IFileLibraryEndpointService.cs:107`
+- Modify: `FileShare-Services/Services/FileLibrary/FileLibraryEndpointService.cs:114`
+- Modify: `FileShare-Services/Endpoints/AppEndpoints.cs:92`
+
+- [ ] **Step 1: Add DeleteFileAsync to IFileLibraryEndpointService.cs**
+
+After line 107 (`SaveFileProgressAsync`), add:
+
+```csharp
+        /// <summary>
+        /// 永久删除指定文件。
+        /// </summary>
+        /// <param name="request">包含文件 ID 的请求。</param>
+        /// <returns>API 响应。</returns>
+        Task<IApiResponse> DeleteFileAsync(DeleteFileRequest request);
+```
+
+- [ ] **Step 2: Implement DeleteFileAsync in FileLibraryEndpointService.cs**
+
+After line 114 (end of `SaveFileProgressAsync`), add:
+
+```csharp
+        /// <inheritdoc />
+        public async Task<IApiResponse> DeleteFileAsync(DeleteFileRequest request)
+        {
+            ValidateFileId(request.Id);
+            await fileLibrary.DeleteFileAsync(request.Id);
+            return ResponseHelper.Succeed("文件已永久删除。");
+        }
+```
+
+- [ ] **Step 3: Register route in AppEndpoints.cs**
+
+After line 92 (the `SaveFileProgress` endpoint), add:
+
+```csharp
+                endpoints.MapPost<IFileLibraryEndpointService, DeleteFileRequest>("api/files/delete", (service, request, _) => service.DeleteFileAsync(request))
+                    .WithOpenApi("FileLibrary", "永久删除文件（物理文件+数据库记录）。")
+                    .WithName("DeleteFile");
+```
+
+---
+
+## Task 3: Frontend — API Method + Components
+
+**Covers:** S3 (frontend delete button and API)
+
+**Files:**
+- Modify: `FileShare-Web-VUE/src/api/index.ts:117`
+- Modify: `FileShare-Web-VUE/src/components/client/FileCard.vue`
+- Modify: `FileShare-Web-VUE/src/components/client/FileListItem.vue`
+- Modify: `FileShare-Web-VUE/src/components/ClientPage.vue`
+
+- [ ] **Step 1: Add deleteFile API method in index.ts**
+
+After line 117 (`saveFileProgress`), add:
+
+```typescript
+  deleteFile: (id: number) =>
+    request('files/delete', { method: 'POST', body: { id } }),
+```
+
+- [ ] **Step 2: Add delete button to FileCard.vue**
+
+Replace the entire `FileCard.vue` content with:
+
+```vue
+<script setup lang="ts">
+import { api, type FileRecordDto } from '../../api'
+import { formatCreatedTime, formatDuration, formatSize } from '../../utils/formatters'
+
+defineProps<{
+  file: FileRecordDto
+  selected?: boolean
+  showCreatedTime?: boolean
+}>()
+
+defineEmits<{
+  select: [file: FileRecordDto]
+  delete: [file: FileRecordDto]
+}>()
+</script>
+
+<template>
+  <button
+    class="file-card"
+    :class="{ active: selected }"
+    type="button"
+    @click="$emit('select', file)"
+  >
+    <span class="delete-btn" @click.stop="$emit('delete', file)" title="永久删除">&times;</span>
+    <img
+      v-if="file.thumbnailUrl"
+      :src="api.thumbnailUrl(file.thumbnailUrl)"
+      class="card-thumb"
+      alt=""
+      loading="lazy"
+    />
+    <div v-else class="card-thumb-placeholder">{{ file.mediaType }}</div>
+    <div class="card-body">
+      <strong>{{ file.fileName }}</strong>
+      <small>
+        {{ formatSize(file.sizeBytes) }}
+        <template v-if="file.videoDuration"> · {{ formatDuration(file.videoDuration) }}</template>
+      </small>
+      <small v-if="showCreatedTime && formatCreatedTime(file)">{{ formatCreatedTime(file) }}</small>
+    </div>
+  </button>
+</template>
+
+<style scoped>
+.delete-btn {
+  position: absolute;
+  top: 4px;
+  right: 4px;
+  width: 22px;
+  height: 22px;
+  border-radius: 50%;
+  background: rgba(0, 0, 0, 0.5);
+  color: #fff;
+  font-size: 14px;
+  line-height: 22px;
+  text-align: center;
+  cursor: pointer;
+  opacity: 0;
+  transition: opacity 0.15s;
+}
+.file-card:hover .delete-btn {
+  opacity: 1;
+}
+.delete-btn:hover {
+  background: #e53e3e;
+}
+</style>
+```
+
+- [ ] **Step 3: Add delete button to FileListItem.vue**
+
+Replace the entire `FileListItem.vue` content with:
+
+```vue
+<script setup lang="ts">
+import { api, type FileRecordDto } from '../../api'
+import { formatCreatedTime, formatDate, formatDuration, formatSize } from '../../utils/formatters'
+
+defineProps<{
+  file: FileRecordDto
+  selected?: boolean
+  showCreatedTime?: boolean
+  showLastPlayed?: boolean
+}>()
+
+defineEmits<{
+  select: [file: FileRecordDto]
+  delete: [file: FileRecordDto]
+}>()
+</script>
+
+<template>
+  <button
+    class="mobile-file"
+    :class="{ active: selected }"
+    type="button"
+    @click="$emit('select', file)"
+  >
+    <img
+      v-if="file.thumbnailUrl"
+      :src="api.thumbnailUrl(file.thumbnailUrl)"
+      class="file-thumb"
+      alt=""
+      loading="lazy"
+    />
+    <span v-else class="type-badge">{{ file.mediaType }}</span>
+    <span>
+      <strong>{{ file.fileName }}</strong>
+      <small>
+        {{ formatSize(file.sizeBytes) }}
+        <template v-if="file.videoDuration"> · {{ formatDuration(file.videoDuration) }}</template>
+        <template v-if="showLastPlayed && file.lastPlayedAt"> · {{ formatDate(file.lastPlayedAt) }}</template>
+      </small>
+      <small v-if="showCreatedTime && formatCreatedTime(file)">{{ formatCreatedTime(file) }}</small>
+    </span>
+    <span class="delete-btn" @click.stop="$emit('delete', file)" title="永久删除">&times;</span>
+  </button>
+</template>
+
+<style scoped>
+.delete-btn {
+  margin-left: auto;
+  padding: 2px 8px;
+  color: #999;
+  font-size: 16px;
+  cursor: pointer;
+  flex-shrink: 0;
+  opacity: 0;
+  transition: opacity 0.15s;
+}
+.mobile-file:hover .delete-btn {
+  opacity: 1;
+}
+.delete-btn:hover {
+  color: #e53e3e;
+}
+</style>
+```
+
+- [ ] **Step 4: Add delete handler and wire events in ClientPage.vue**
+
+In `<script setup>`, after the existing `saveFileProgress` function (search for `async function saveFileProgress`), add:
+
+```typescript
+async function deleteFile(file: FileRecordDto) {
+  if (!window.confirm(`确定要永久删除 "${file.fileName}" 吗？\n\n删除后无法恢复！`)) {
+    return
+  }
+  try {
+    await api.deleteFile(file.id)
+    // 刷新当前浏览数据
+    if (browseData.value) {
+      await loadBrowse()
+    }
+    // 刷新搜索结果
+    if (searchResults.value.length > 0) {
+      await loadSearch()
+    }
+    // 清除选中状态
+    if (selectedFile.value?.id === file.id) {
+      selectedFile.value = null
+    }
+  } catch (error) {
+    errorMessage.value = error instanceof Error ? error.message : '删除失败'
+  }
+}
+```
+
+In the template, find each `<FileCard` and `<FileListItem` usage and add `@delete="deleteFile"`:
+
+For the `displayedFiles` grid (around line 628):
+```vue
+<FileCard
+  :file="file"
+  :selected="selectedFile?.id === file.id"
+  show-created-time
+  @select="selectFile"
+  @delete="deleteFile"
+/>
+```
+
+For the `displayedFiles` list (around line 659):
+```vue
+<FileListItem
+  :file="file"
+  :selected="selectedFile?.id === file.id"
+  show-created-time
+  @select="selectFile"
+  @delete="deleteFile"
+/>
+```
+
+For the `searchResults` grid (around line 466):
+```vue
+<FileCard :file="file" show-created-time @select="selectSearchFile" @delete="deleteFile" />
+```
+
+For the `searchResults` list (around line 491):
+```vue
+<FileListItem :file="file" show-created-time @select="selectSearchFile" @delete="deleteFile" />
+```
+
+For the `recentFiles` grid (around line 534):
+```vue
+<FileCard :file="file" :selected="selectedFile?.id === file.id" @select="selectFile" @delete="deleteFile" />
+```
+
+For the `recentFiles` list (around line 559):
+```vue
+<FileListItem :file="file" :selected="selectedFile?.id === file.id" @select="selectFile" @delete="deleteFile" />
+```
+
+---
+
+## Task 4: Verify
+
+**Covers:** S4, S5
+
+- [ ] **Step 1: Build backend**
+
+```bash
+dotnet build FileShare-API/FileShare-API.csproj
+```
+
+- [ ] **Step 2: Build frontend**
+
+```bash
+cd FileShare-Web-VUE && npx vue-tsc --noEmit
+```
+
+- [ ] **Step 3: Verify no regressions**
+
+Ensure existing functionality still works by checking the build passes.