diff --git a/chat_web_front/src/components/PdfViewer.vue b/chat_web_front/src/components/PdfViewer.vue
index b5e8e07..072f977 100644
--- a/chat_web_front/src/components/PdfViewer.vue
+++ b/chat_web_front/src/components/PdfViewer.vue
@@ -12,7 +12,7 @@
 </template>
 
 <script setup lang="ts">
-import { ref, onMounted, onBeforeUnmount, nextTick, watch } from 'vue';
+import { ref, onMounted, onBeforeUnmount, nextTick, watch, toRaw } from 'vue';
 import * as pdfjsLib from 'pdfjs-dist';
 import { renderTextLayer } from 'pdfjs-dist';
 
@@ -74,9 +74,9 @@ const loadPdf = async () => {
   loading.value = true;
   error.value = '';
   try {
-    const loadingTask = pdfjsLib.getDocument({
-      data: props.src instanceof ArrayBuffer ? new Uint8Array(props.src) : props.src
-    });
+    const rawSrc = toRaw(props.src);
+    const data = rawSrc instanceof ArrayBuffer ? new Uint8Array(rawSrc) : rawSrc;
+    const loadingTask = pdfjsLib.getDocument({ data });
     pdfDoc = await loadingTask.promise;
     const numPages = pdfDoc.numPages;
     pages.value = Array.from({ length: numPages }, (_, i) => i + 1);
diff --git a/chat_web_front/src/views/reading/index.vue b/chat_web_front/src/views/reading/index.vue
index 6526d50..4bc023b 100644
--- a/chat_web_front/src/views/reading/index.vue
+++ b/chat_web_front/src/views/reading/index.vue
@@ -460,7 +460,11 @@ const loadPdfFile = async () => {
       params: { fileId: selectedFile.value.fileId },
       responseType: 'arraybuffer'
     });
-    pdfData.value = resp.data;
+    // 复制 ArrayBuffer 避免被 Vue 响应式代理导致 detached
+    const src = resp.data as ArrayBuffer;
+    const copy = new ArrayBuffer(src.byteLength);
+    new Uint8Array(copy).set(new Uint8Array(src));
+    pdfData.value = copy;
   } catch (e: any) {
     pdfData.value = null;
     docHtml.value = '<p style="color:#999;text-align:center;margin-top:40px;">PDF 文件加载失败</p>';
diff --git a/langchain-chat/server/knowledge_base/file_converter.py b/langchain-chat/server/knowledge_base/file_converter.py
index 9fca692..b75d5bb 100644
--- a/langchain-chat/server/knowledge_base/file_converter.py
+++ b/langchain-chat/server/knowledge_base/file_converter.py
@@ -948,9 +948,11 @@ class FileConverter:
 
             css = '''<style>
 .pdf-preview { font-family: system-ui, -apple-system, sans-serif; line-height: 1.6; max-width: 100%; }
+.pdf-preview > div { width: 100% !important; max-width: 100% !important; }
 .pdf-preview img { max-width: 100%; height: auto; }
 .pdf-preview p { margin: 0.3em 0; }
 .pdf-preview span { line-height: 1.5; }
+.pdf-page > div { width: 100% !important; max-width: 100% !important; }
 </style>'''
 
             if not any_text: