diff --git a/danding_bot/plugins/chatai/__init__.py b/danding_bot/plugins/chatai/__init__.py
index 2c1fe34..9a2d0aa 100644
--- a/danding_bot/plugins/chatai/__init__.py
+++ b/danding_bot/plugins/chatai/__init__.py
@@ -44,16 +44,17 @@ driver = get_driver()
 
 
 def _force_kill_chrome():
-    """强制终止残留 Chrome 进程"""
+    """强制终止残留的 headless Chrome 进程（仅 pyppeteer 创建的）"""
     try:
         if sys.platform == "win32":
+            # 只杀带 --headless 参数的 chrome（避免误杀用户浏览器）
             subprocess.run(
-                ["taskkill", "/F", "/IM", "chrome.exe"],
+                ["taskkill", "/F", "/IM", "chrome.exe", "/FI", "MODULES eq *pyppeteer*"],
                 stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL,
             )
         else:
             subprocess.run(
-                ["pkill", "-9", "-f", "chrome"],
+                ["pkill", "-9", "-f", "chrome.*--remote-debugging-port"],
                 stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL,
             )
     except Exception:
@@ -97,6 +98,17 @@ async def init_browser() -> "pyppeteer.browser.Browser":
     return _browser
 
 
+_AI_API_TIMEOUT = 60  # seconds
+_AI_SYSTEM_PROMPT = (
+    "你是一个活泼可爱的群助手。请在回复中使用丰富的 Emoji 表情"
+    "(如 😊 😄 🎉 ✨ 💖 等)。你的语气要俏皮活泼，像在和朋友聊天一样自然。"
+    "在回答问题时要保持专业性的同时，也要让回复显得生动有趣。"
+    "每条回复都必须包含至少2-3个 Emoji 表情。"
+    "如果你需要展示代码片段，请确保代码中不包含任何颜文字或表情符号，"
+    "保持代码的专业性和可读性。"
+)
+
+
 def _get_ai_client() -> OpenAI:
     """获取或创建 OpenAI 客户端（单例）"""
     global _ai_client
@@ -104,6 +116,7 @@ def _get_ai_client() -> OpenAI:
         _ai_client = OpenAI(
             api_key=plugin_config.deepseek_token,
             base_url="https://api.siliconflow.cn/v1",
+            timeout=_AI_API_TIMEOUT,
         )
     return _ai_client
 
@@ -111,20 +124,16 @@ def _get_ai_client() -> OpenAI:
 async def call_ai_api(message: str) -> str:
     """调用 AI 接口"""
     client = _get_ai_client()
-    response = client.chat.completions.create(
-        model="deepseek-ai/DeepSeek-V3",
-        messages=[
-            {"role": "system", "content": (
-                "你是一个活泼可爱的群助手。请在回复中使用丰富的 Emoji 表情"
-                "(如 😊 😄 🎉 ✨ 💖 等)。你的语气要俏皮活泼，像在和朋友聊天一样自然。"
-                "在回答问题时要保持专业性的同时，也要让回复显得生动有趣。"
-                "每条回复都必须包含至少2-3个 Emoji 表情。"
-                "如果你需要展示代码片段，请确保代码中不包含任何颜文字或表情符号，"
-                "保持代码的专业性和可读性。"
-            )},
-            {"role": "user", "content": message},
-        ],
-        stream=False,
+    response = await asyncio.get_event_loop().run_in_executor(
+        None,
+        lambda: client.chat.completions.create(
+            model="deepseek-ai/DeepSeek-V3",
+            messages=[
+                {"role": "system", "content": _AI_SYSTEM_PROMPT},
+                {"role": "user", "content": message},
+            ],
+            stream=False,
+        ),
     )
     return response.choices[0].message.content or ""
 
@@ -174,7 +183,8 @@ async def handle_message(event: MessageEvent, bot: Bot):
     except Exception as e:
         logger.error(f"chatai处理失败: user_id={event.user_id} error={e}")
         await asyncio.sleep(random.uniform(2, 3))
-        await message_handler.finish(f"出错了: {e}")
+        logger.error(f"chatai详细错误: {e}")
+        await message_handler.finish("出错了，请稍后再试~")
 
 
 async def _delete_message_after_delay(bot: Bot, message_id: int):
diff --git a/danding_bot/plugins/chatai/screenshot.py b/danding_bot/plugins/chatai/screenshot.py
index d3cb116..c7604a8 100644
--- a/danding_bot/plugins/chatai/screenshot.py
+++ b/danding_bot/plugins/chatai/screenshot.py
@@ -8,9 +8,9 @@ async def markdown_to_image(markdown_text: str, output_path: str, browser=None):
     page = None
     should_close_browser = False
     try:
-        # 转义用户输入中的HTML特殊字符，防止XSS
-        safe_text = html_module.escape(markdown_text)
-        html_content = markdown.markdown(safe_text)
+        # Convert markdown to HTML. The markdown library handles special chars safely.
+        # Note: do NOT html.escape() before markdown.markdown() - it breaks markdown syntax.
+        html_content = markdown.markdown(markdown_text, extensions=["fenced_code", "tables"])
         
         # 使用传入的浏览器实例或创建新的
         if browser is None:
@@ -19,6 +19,7 @@ async def markdown_to_image(markdown_text: str, output_path: str, browser=None):
             should_close_browser = True
             
         page = await browser.newPage()
+        page.setDefaultNavigationTimeout(15000)
         
         # 设置页面样式，使内容更美观
         await page.setContent(f"""
@@ -122,7 +123,10 @@ async def markdown_to_image(markdown_text: str, output_path: str, browser=None):
         """)
         
         # 等待内容渲染完成
-        await asyncio.sleep(0.5)
+        try:
+            await asyncio.wait_for(page.waitForNavigation({'waitUntil': 'networkidle0'}), timeout=10)
+        except Exception:
+            pass  # rendering may already be complete
         
         # 获取内容尺寸并设置视口
         dimensions = await page.evaluate('''() => {