diff --git a/backend/competition/views.py b/backend/competition/views.py
index 7ee49b7..da02fb7 100644
--- a/backend/competition/views.py
+++ b/backend/competition/views.py
@@ -1,5 +1,6 @@
 from rest_framework import viewsets, permissions, status, filters, serializers
-from rest_framework.decorators import action, api_view, permission_classes, csrf_exempt
+from django.views.decorators.csrf import csrf_exempt
+from rest_framework.decorators import action, api_view, permission_classes
 from rest_framework.response import Response
 from rest_framework.views import APIView
 from django.db.models import Q
diff --git a/backend/config/settings.py b/backend/config/settings.py
index d7cd9f8..fb4a058 100644
--- a/backend/config/settings.py
+++ b/backend/config/settings.py
@@ -119,16 +119,16 @@ if DB_HOST:
     }
 
 
-DB_HOST = os.environ.get('DB_HOST', '121.43.104.161')
-if DB_HOST:
-    DATABASES['default'] = {
-        'ENGINE': 'django.db.backends.postgresql',
-        'NAME': os.environ.get('DB_NAME', 'market'),
-        'USER': os.environ.get('DB_USER', 'market'),
-        'PASSWORD': os.environ.get('DB_PASSWORD', '123market'),
-        'HOST': DB_HOST,
-        'PORT': os.environ.get('DB_PORT', '6433'),
-    }
+# DB_HOST = os.environ.get('DB_HOST', '121.43.104.161')
+# if DB_HOST:
+#     DATABASES['default'] = {
+#         'ENGINE': 'django.db.backends.postgresql',
+#         'NAME': os.environ.get('DB_NAME', 'market'),
+#         'USER': os.environ.get('DB_USER', 'market'),
+#         'PASSWORD': os.environ.get('DB_PASSWORD', '123market'),
+#         'HOST': DB_HOST,
+#         'PORT': os.environ.get('DB_PORT', '6433'),
+#     }
 
 
 # Password validation
diff --git a/miniprogram/src/pages/competition/project.tsx b/miniprogram/src/pages/competition/project.tsx
index 942898b..f8425b5 100644
--- a/miniprogram/src/pages/competition/project.tsx
+++ b/miniprogram/src/pages/competition/project.tsx
@@ -125,22 +125,71 @@ export default function ProjectEdit() {
           
           Taro.hideLoading()
           Taro.showToast({ title: '上传成功', icon: 'success' })
-      } catch (e) {
+      } catch (e: any) {
           Taro.hideLoading()
           console.error(e)
-          Taro.showToast({ title: '上传失败', icon: 'none' })
+          const errorMsg = e.response?.error || e.message || '上传失败'
+          Taro.showToast({ title: errorMsg, icon: 'none' })
       }
   }
 
-  const handleDeleteFile = (fileId) => {
-      // API call to delete file not implemented yet? Or just remove from list?
-      // Usually we should call delete API. For now just remove from UI.
-      // Ideally we should have deleteProjectFile API.
-      // But user only asked to "optimize upload".
-      setProject(prev => ({
-          ...prev,
-          files: prev.files.filter(f => f.id !== fileId)
-      }))
+  const handleDeleteFile = async (fileId) => {
+      try {
+          await Taro.showModal({
+              title: '确认删除',
+              content: '确定要删除这个文件吗？',
+              confirmColor: '#ff4d4f'
+          }).then(res => {
+              if (!res.confirm) throw new Error('cancel')
+          })
+          
+          Taro.showLoading({ title: '删除中...' })
+          await deleteProjectFile(fileId)
+          
+          setProject(prev => ({
+              ...prev,
+              files: prev.files.filter(f => f.id !== fileId)
+          }))
+          
+          Taro.hideLoading()
+          Taro.showToast({ title: '删除成功', icon: 'success' })
+      } catch (e: any) {
+          Taro.hideLoading()
+          if (e.message !== 'cancel') {
+              const errorMsg = e.response?.error || e.message || '删除失败'
+              Taro.showToast({ title: errorMsg, icon: 'none' })
+          }
+      }
+  }
+
+  const handlePreviewFile = (file) => {
+      const fileUrl = file.file_url || file.file_url_display || ''
+      if (!fileUrl) {
+          Taro.showToast({ title: '文件地址无效', icon: 'none' })
+          return
+      }
+      
+      const fileType = file.file_type || ''
+      if (fileType === 'image') {
+          Taro.previewImage({
+              urls: [fileUrl]
+          })
+      } else {
+          Taro.downloadFile({
+              url: fileUrl,
+              success: (res) => {
+                  if (res.statusCode === 200) {
+                      Taro.openDocument({
+                          filePath: res.tempFilePath,
+                          fileType: fileType === 'pdf' ? 'pdf' : fileType === 'ppt' ? 'ppt' : undefined
+                      })
+                  }
+              },
+              fail: () => {
+                  Taro.showToast({ title: '打开文件失败', icon: 'none' })
+              }
+          })
+      }
   }
 
   const handleSave = async (submit = false) => {
@@ -262,9 +311,14 @@ export default function ProjectEdit() {
             </View>
             <View className='file-list'>
                 {project.files && project.files.map((file, index) => (
-                    <View key={index} className='file-item' style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', padding: '10px', background: '#f8f8f8', marginBottom: '8px', borderRadius: '4px' }}>
+                    <View 
+                        key={index} 
+                        className='file-item' 
+                        style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', padding: '10px', background: '#f8f8f8', marginBottom: '8px', borderRadius: '4px' }}
+                        onClick={() => handlePreviewFile(file)}
+                    >
                         <Text className='file-name' style={{ flex: 1, fontSize: '14px', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{file.name || '未知文件'}</Text>
-                        {/* <Text className='delete' style={{ color: 'red', marginLeft: '10px' }} onClick={() => handleDeleteFile(file.id)}>删除</Text> */}
+                        <Text className='delete' style={{ color: '#ff4d4f', marginLeft: '10px', fontSize: '14px' }} onClick={(e) => { e.stopPropagation(); handleDeleteFile(file.id) }}>删除</Text>
                     </View>
                 ))}
                 {(!project.files || project.files.length === 0) && <Text style={{ color: '#999', fontSize: '12px' }}>暂无附件 (PDF/PPT/视频)</Text>}