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diff --git a/backend/app/api/v1/files.py b/backend/app/api/v1/files.py
index 94e0071..8c826ef 100644
--- a/backend/app/api/v1/files.py
+++ b/backend/app/api/v1/files.py
@@ -28,6 +28,7 @@ from app.schemas.response import success_response
 from app.services.storage import storage_service
 from app.services.log_service import log_service
 from app.services.notification_service import notification_service
+from app.services.search_service import search_service
 from app.core.enums import OperationType
 
 router = APIRouter()
@@ -145,6 +146,11 @@ async def save_file(
     # 写入文件内容
     await storage_service.write_file(file_path, file_data.content)
 
+    # 更新搜索索引 (仅限 Markdown)
+    if file_data.path.endswith('.md'):
+        file_title = Path(file_data.path).stem
+        await search_service.update_doc(project_id, file_data.path, file_title, file_data.content)
+
     # 记录操作日志
     await log_service.log_file_operation(
         db=db,
@@ -188,6 +194,11 @@ async def operate_file(
     if operation.action == "delete":
         # 删除文件或文件夹
         await storage_service.delete_file(current_path)
+        
+        # 删除索引
+        if operation.path.endswith('.md'):
+            await search_service.remove_doc(project_id, operation.path)
+            
         # 记录日志
         await log_service.log_file_operation(
             db=db,
@@ -216,6 +227,21 @@ async def operate_file(
             raise HTTPException(status_code=400, detail="缺少新路径参数")
         new_path = storage_service.get_secure_path(project.storage_key, operation.new_path)
         await storage_service.rename_file(current_path, new_path)
+        
+        # 更新索引 (删除旧的，添加新的 - 如果内容未变也需要重新读取内容吗？
+        # 优化：Whoosh 更新需要内容。我们可以尝试读取文件内容。
+        # 如果是目录重命名，比较复杂，暂时忽略目录重命名的递归索引更新，或者后续实现重建索引功能)
+        if operation.path.endswith('.md') and operation.new_path.endswith('.md'):
+            # 简单处理：读取新文件内容并更新索引
+            try:
+                content = await storage_service.read_file(new_path)
+                file_title = Path(operation.new_path).stem
+                await search_service.remove_doc(project_id, operation.path)
+                await search_service.update_doc(project_id, operation.new_path, file_title, content)
+            except Exception as e:
+                # 忽略索引更新错误
+                pass
+
         # 记录日志
         await log_service.log_file_operation(
             db=db,
@@ -245,6 +271,17 @@ async def operate_file(
             raise HTTPException(status_code=400, detail="缺少目标路径参数")
         new_path = storage_service.get_secure_path(project.storage_key, operation.new_path)
         await storage_service.rename_file(current_path, new_path)
+        
+        # 更新索引
+        if operation.path.endswith('.md') and operation.new_path.endswith('.md'):
+            try:
+                content = await storage_service.read_file(new_path)
+                file_title = Path(operation.new_path).stem
+                await search_service.remove_doc(project_id, operation.path)
+                await search_service.update_doc(project_id, operation.new_path, file_title, content)
+            except Exception:
+                pass
+
         # 记录日志
         await log_service.log_file_operation(
             db=db,
@@ -297,6 +334,12 @@ async def operate_file(
         # 创建文件
         content = operation.content or ""
         await storage_service.write_file(current_path, content)
+        
+        # 更新索引
+        if operation.path.endswith('.md'):
+            file_title = Path(operation.path).stem
+            await search_service.update_doc(project_id, operation.path, file_title, content)
+
         # 记录日志
         await log_service.log_file_operation(
             db=db,
@@ -374,11 +417,6 @@ async def upload_document(
 ):
     """
     上传文档文件（PDF等）到项目目录
-
-    Args:
-        project_id: 项目ID
-        file: 上传的文件
-        target_dir: 目标目录（相对路径，如 "docs" 或 "docs/manuals"，空字符串表示根目录）
     """
     project = await check_project_access(project_id, current_user, db, require_write=True)
 
@@ -421,10 +459,6 @@ async def get_document_file(
 ):
     """
     获取文档文件（PDF等）- 支持 HTTP Range 请求
-
-    Args:
-        project_id: 项目ID
-        path: 文件相对路径（如 "manual.pdf" 或 "docs/guide.pdf"）
     """
     import re
     import aiofiles
@@ -564,6 +598,14 @@ async def import_documents(
         # 构建相对路径
         relative_path = f"{target_path}/{file.filename}" if target_path else file.filename
         imported_files.append(relative_path)
+        
+        # 更新索引
+        try:
+            text_content = content.decode('utf-8')
+            file_title = Path(file.filename).stem
+            await search_service.update_doc(project_id, relative_path, file_title, text_content)
+        except Exception:
+            pass
 
     # 记录日志
     await log_service.log_file_operation(
@@ -641,4 +683,4 @@ async def export_directory(
         headers={
             "Content-Disposition": f"attachment; filename={zip_filename}"
         }
-    )
+    )
\ No newline at end of file
diff --git a/backend/app/api/v1/notifications.py b/backend/app/api/v1/notifications.py
index 8a36101..4903bdc 100644
--- a/backend/app/api/v1/notifications.py
+++ b/backend/app/api/v1/notifications.py
@@ -1,21 +1,16 @@
 """
-通知管理 API
+通知管理 API (Redis版)
 """
-from fastapi import APIRouter, Depends, HTTPException, Request
-from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy import select, update, func, desc
-from typing import List, Optional
+from fastapi import APIRouter, Depends, HTTPException
+from typing import List, Union
 from datetime import datetime
 
 from app.core.database import get_db
 from app.core.deps import get_current_user
 from app.models.user import User
-from app.models.notification import Notification
 from app.schemas.notification import (
     NotificationResponse,
-    NotificationUpdate,
-    UnreadCountResponse,
-    NotificationCreate
+    NotificationCreate,
 )
 from app.schemas.response import success_response
 from app.services.notification_service import notification_service
@@ -27,97 +22,75 @@ router = APIRouter()
 async def get_notifications(
     page: int = 1,
     page_size: int = 20,
-    unread_only: bool = False,
     current_user: User = Depends(get_current_user),
-    db: AsyncSession = Depends(get_db)
 ):
-    """获取当前用户的通知列表"""
-    query = select(Notification).where(Notification.user_id == current_user.id)
-    
-    if unread_only:
-        query = query.where(Notification.is_read == 0)
-    
-    query = query.order_by(desc(Notification.created_at))
-    
-    # 分页
-    offset = (page - 1) * page_size
-    query = query.offset(offset).limit(page_size)
-    
-    result = await db.execute(query)
-    notifications = result.scalars().all()
-    
-    # 获取总数
-    count_query = select(func.count()).select_from(Notification).where(Notification.user_id == current_user.id)
-    if unread_only:
-        count_query = count_query.where(Notification.is_read == 0)
-    total_result = await db.execute(count_query)
-    total = total_result.scalar()
+    """获取当前用户的通知列表 (从 Redis 读取)"""
+    try:
+        skip = (page - 1) * page_size
+        notifications = await notification_service.get_user_notifications(
+            user_id=current_user.id,
+            limit=page_size,
+            skip=skip
+        )
+        
+        # 获取总数 (ZCARD)
+        from app.core.redis_client import get_redis
+        redis = get_redis()
+        total = 0
+        if redis:
+            key = notification_service._get_order_key(current_user.id)
+            total = await redis.zcard(key)
 
-    data = [NotificationResponse.from_orm(n).dict() for n in notifications]
-    return {
-        "code": 200,
-        "message": "success",
-        "data": data,
-        "total": total,
-        "page": page,
-        "page_size": page_size
-    }
+        return {
+            "code": 200,
+            "message": "success",
+            "data": notifications,
+            "total": total,
+            "page": page,
+            "page_size": page_size
+        }
+    except Exception as e:
+        # 降级处理，防止 500
+        print(f"Error fetching notifications: {e}")
+        return {
+            "code": 200,
+            "message": "success",
+            "data": [],
+            "total": 0,
+            "page": page,
+            "page_size": page_size
+        }
 
 
 @router.get("/unread-count", response_model=dict)
 async def get_unread_count(
     current_user: User = Depends(get_current_user),
-    db: AsyncSession = Depends(get_db)
 ):
     """获取未读通知数量"""
-    result = await db.execute(
-        select(func.count()).select_from(Notification).where(
-            Notification.user_id == current_user.id,
-            Notification.is_read == 0
-        )
-    )
-    count = result.scalar()
-    return success_response(data={"unread_count": count})
+    try:
+        count = await notification_service.get_unread_count(current_user.id)
+        return success_response(data={"unread_count": count})
+    except Exception as e:
+        print(f"Error fetching unread count: {e}")
+        return success_response(data={"unread_count": 0})
 
 
 @router.put("/{notification_id}/read", response_model=dict)
 async def mark_as_read(
-    notification_id: int,
+    notification_id: str,
     current_user: User = Depends(get_current_user),
-    db: AsyncSession = Depends(get_db)
 ):
     """标记单条通知为已读"""
-    result = await db.execute(
-        select(Notification).where(
-            Notification.id == notification_id,
-            Notification.user_id == current_user.id
-        )
-    )
-    notification = result.scalar_one_or_none()
-    
-    if not notification:
-        raise HTTPException(status_code=404, detail="通知不存在")
-    
-    if notification.is_read == 0:
-        notification.is_read = 1
-        notification.read_at = datetime.now()
-        await db.commit()
-    
+    await notification_service.mark_read(current_user.id, notification_id)
     return success_response(message="已标记为已读")
 
 
 @router.put("/read-all", response_model=dict)
 async def mark_all_as_read(
     current_user: User = Depends(get_current_user),
-    db: AsyncSession = Depends(get_db)
 ):
     """标记所有通知为已读"""
-    await db.execute(
-        update(Notification)
-        .where(Notification.user_id == current_user.id, Notification.is_read == 0)
-        .values(is_read=1, read_at=datetime.now())
-    )
-    await db.commit()
+    await notification_service.mark_all_read(current_user.id)
     return success_response(message="全部标记为已读")
 
 
@@ -125,14 +98,14 @@ async def mark_all_as_read(
 async def send_system_notification(
     notification_in: NotificationCreate,
     current_user: User = Depends(get_current_user),
-    db: AsyncSession = Depends(get_db)
 ):
     """发送系统通知（仅限超级管理员）"""
     if not current_user.is_superuser:
         raise HTTPException(status_code=403, detail="只有管理员可以发送系统通知")
     
+    # 這裡我们传 db=None 因为 service 已经不需要 db 写操作了
     await notification_service.create_notification(
-        db=db,
+        db=None, 
         user_id=notification_in.user_id,
         title=notification_in.title,
         content=notification_in.content,
@@ -140,5 +113,4 @@ async def send_system_notification(
         category="system",
         link=notification_in.link
     )
-    await db.commit()
     return success_response(message="系统通知发送成功")
diff --git a/backend/app/api/v1/projects.py b/backend/app/api/v1/projects.py
index 3d4cc50..95e5a4d 100644
--- a/backend/app/api/v1/projects.py
+++ b/backend/app/api/v1/projects.py
@@ -32,6 +32,22 @@ from app.core.enums import OperationType, ResourceType
 router = APIRouter()
 
 
+def get_document_count(storage_key: str) -> int:
+    """计算项目中的文档数量（.md 和 .pdf）"""
+    try:
+        project_path = storage_service.get_secure_path(storage_key)
+        if not project_path.exists():
+            return 0
+        md_count = len(list(project_path.rglob("*.md")))
+        pdf_count = len(list(project_path.rglob("*.pdf")))
+        # 排除 _assets 目录下的文件
+        assets_md = len(list((project_path / "_assets").rglob("*.md"))) if (project_path / "_assets").exists() else 0
+        assets_pdf = len(list((project_path / "_assets").rglob("*.pdf"))) if (project_path / "_assets").exists() else 0
+        return md_count + pdf_count - assets_md - assets_pdf
+    except Exception:
+        return 0
+
+
 @router.get("/", response_model=dict)
 async def get_my_projects(
     current_user: User = Depends(get_current_user),
@@ -58,7 +74,11 @@ async def get_my_projects(
 
     # 合并结果
     all_projects = owned_projects + member_projects
-    projects_data = [ProjectResponse.from_orm(p).dict() for p in all_projects]
+    projects_data = []
+    for p in all_projects:
+        p_dict = ProjectResponse.from_orm(p).dict()
+        p_dict['doc_count'] = get_document_count(p.storage_key)
+        projects_data.append(p_dict)
 
     return success_response(data=projects_data)
 
@@ -73,7 +93,11 @@ async def get_owned_projects(
         select(Project).where(Project.owner_id == current_user.id, Project.status == 1)
     )
     projects = result.scalars().all()
-    projects_data = [ProjectResponse.from_orm(p).dict() for p in projects]
+    projects_data = []
+    for p in projects:
+        p_dict = ProjectResponse.from_orm(p).dict()
+        p_dict['doc_count'] = get_document_count(p.storage_key)
+        projects_data.append(p_dict)
     return success_response(data=projects_data)
 
 
@@ -101,6 +125,7 @@ async def get_shared_projects(
         project_dict['owner_name'] = owner.username
         project_dict['owner_nickname'] = owner.nickname
         project_dict['user_role'] = member.role  # 添加用户角色
+        project_dict['doc_count'] = get_document_count(project.storage_key)
         projects_data.append(project_dict)
 
     return success_response(data=projects_data)
@@ -188,7 +213,7 @@ async def get_project(
         if not member and project.is_public != 1:
             raise HTTPException(status_code=403, detail="无权访问该项目")
 
-    # 增加访问次数
+    # 增加访问次数 (简单计数)
     project.visit_count += 1
     await db.commit()
 
diff --git a/backend/app/api/v1/search.py b/backend/app/api/v1/search.py
index ed23022..264a4ea 100644
--- a/backend/app/api/v1/search.py
+++ b/backend/app/api/v1/search.py
@@ -1,128 +1,270 @@
 """
 文档搜索相关 API
 """
-from fastapi import APIRouter, Depends, HTTPException, Query
+from fastapi import APIRouter, Depends, HTTPException, Query, BackgroundTasks
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy import select, or_
-import os
-import glob
+from typing import Optional, List
+from pathlib import Path
+import logging
 
 from app.core.database import get_db
 from app.core.deps import get_current_user
 from app.models.user import User
 from app.models.project import Project, ProjectMember
+from app.services.search_service import search_service
 from app.services.storage import storage_service
 from app.schemas.response import success_response
 
 router = APIRouter()
-
+logger = logging.getLogger(__name__)
 
 @router.get("/documents", response_model=dict)
 async def search_documents(
     keyword: str = Query(..., min_length=1, description="搜索关键词"),
+    project_id: Optional[int] = Query(None, description="限制在指定项目中搜索"),
     current_user: User = Depends(get_current_user),
     db: AsyncSession = Depends(get_db)
 ):
     """
-    文档搜索（简化版）
-    搜索范围：项目名称、项目描述、文件名（支持.md和.pdf）
+    文档搜索 (混合模式：Whoosh 全文检索 + 数据库项目搜索 + 文件系统文件名搜索 fallback)
     """
-    if not keyword:
-        return success_response(data=[])
+    try:
+        if not keyword:
+            return success_response(data=[])
 
-    keyword_lower = keyword.lower()
+        # 1. 确定搜索范围 (项目ID列表)
+        allowed_project_ids = []
+        
+        if project_id:
+            # 检查指定项目的访问权限
+            result = await db.execute(select(Project).where(Project.id == project_id))
+            project = result.scalar_one_or_none()
+            
+            if not project:
+                raise HTTPException(status_code=404, detail="项目不存在")
+                
+            # 检查权限
+            if project.owner_id != current_user.id and project.is_public != 1:
+                member_result = await db.execute(
+                    select(ProjectMember).where(
+                        ProjectMember.project_id == project_id,
+                        ProjectMember.user_id == current_user.id
+                    )
+                )
+                if not member_result.scalar_one_or_none():
+                    raise HTTPException(status_code=403, detail="无权访问该项目")
+            
+            allowed_project_ids.append(str(project_id))
+        else:
+            # 获取所有可访问的项目
+            # 1. 用户创建的项目
+            owned_result = await db.execute(
+                select(Project.id).where(Project.owner_id == current_user.id, Project.status == 1)
+            )
+            allowed_project_ids.extend([str(pid) for pid in owned_result.scalars().all()])
 
-    # 获取用户有权限访问的项目
-    # 1. 用户创建的项目
-    owned_projects_result = await db.execute(
-        select(Project).where(Project.owner_id == current_user.id, Project.status == 1)
-    )
-    owned_projects = owned_projects_result.scalars().all()
+            # 2. 用户参与的项目
+            member_result = await db.execute(
+                select(ProjectMember.project_id)
+                .join(Project, ProjectMember.project_id == Project.id)
+                .where(
+                    ProjectMember.user_id == current_user.id,
+                    Project.status == 1
+                )
+            )
+            allowed_project_ids.extend([str(pid) for pid in member_result.scalars().all()])
+            
+            # 去重
+            allowed_project_ids = list(set(allowed_project_ids))
 
-    # 2. 用户参与的项目
-    member_projects_result = await db.execute(
-        select(Project)
-        .join(ProjectMember, ProjectMember.project_id == Project.id)
-        .where(
-            ProjectMember.user_id == current_user.id,
-            Project.owner_id != current_user.id,
-            Project.status == 1
-        )
-    )
-    member_projects = member_projects_result.scalars().all()
+        if not allowed_project_ids:
+            return success_response(data=[])
 
-    # 合并所有可访问的项目
-    all_projects = owned_projects + member_projects
+        # 2. 执行搜索
+        search_results = []
+        
+        # A. 数据库项目搜索 (仅当未指定 project_id 时，或者需要搜项目本身)
+        # 如果前端指定了 project_id，通常是在项目内搜文件，不需要搜项目本身
+        if not project_id:
+            projects_query = select(Project).where(
+                Project.id.in_(allowed_project_ids),
+                or_(
+                    Project.name.ilike(f"%{keyword}%"),
+                    Project.description.ilike(f"%{keyword}%")
+                )
+            )
+            project_res = await db.execute(projects_query)
+            matched_projects = project_res.scalars().all()
+            
+            for proj in matched_projects:
+                search_results.append({
+                    "type": "project",
+                    "project_id": proj.id,
+                    "project_name": proj.name,
+                    "project_description": proj.description or "",
+                    "match_type": "项目名称/描述",
+                })
 
-    # 搜索结果列表
-    search_results = []
+        # B. Whoosh 全文检索
+        whoosh_results = []
+        try:
+            if project_id:
+                whoosh_results = await search_service.search(keyword, str(project_id))
+            else:
+                # 全局搜索
+                whoosh_results = await search_service.search(keyword, limit=50)
+                # 过滤权限
+                whoosh_results = [r for r in whoosh_results if str(r['project_id']) in allowed_project_ids]
+        except Exception as e:
+            logger.warning(f"Whoosh search failed: {e}")
+            pass
+            
+        # 获取 Whoosh 结果涉及的项目 ID
+        whoosh_project_ids = set(res['project_id'] for res in whoosh_results if res.get('project_id'))
+        
+        # 查询项目名称映射
+        project_name_map = {}
+        if whoosh_project_ids:
+            p_res = await db.execute(select(Project.id, Project.name).where(Project.id.in_(whoosh_project_ids)))
+            for pid, pname in p_res.all():
+                project_name_map[str(pid)] = pname
 
-    # 搜索项目和文件
-    for project in all_projects:
-        # 检查项目名称或描述是否匹配
-        project_matched = False
-        if keyword_lower in project.name.lower():
-            project_matched = True
-        elif project.description and keyword_lower in project.description.lower():
-            project_matched = True
-
-        # 如果项目本身匹配，添加到结果
-        if project_matched:
+        # 添加 Whoosh 结果
+        for res in whoosh_results:
+            pid_str = str(res['project_id'])
             search_results.append({
-                "type": "project",
-                "project_id": project.id,
-                "project_name": project.name,
-                "project_description": project.description or "",
-                "match_type": "项目",
+                "type": "file",
+                "project_id": res['project_id'],
+                "project_name": project_name_map.get(pid_str, "未知项目"),
+                "file_path": res['path'],
+                "file_name": res['title'],
+                "highlights": res.get('highlights'),
+                "match_type": "全文检索"
             })
 
-        # 搜索项目中的文件名
-        try:
-            project_path = storage_service.get_secure_path(project.storage_key)
+        # C. 文件系统文件名搜索 (Fallback / Complementary)
+        # 为了保证未索引的文件也能通过文件名搜到
+        
+        # 获取需要扫描的项目
+        projects_to_scan = []
+        if project_id:
+             # 单项目扫描
+             res = await db.execute(select(Project).where(Project.id == project_id))
+             p = res.scalar_one_or_none()
+             if p: projects_to_scan = [p]
+        elif len(search_results) < 20: 
+             # 全局扫描：仅当结果较少时才进行全盘扫描，避免性能问题
+             # 这是一个简单的启发式策略
+             res = await db.execute(select(Project).where(Project.id.in_(allowed_project_ids)))
+             projects_to_scan = res.scalars().all()
 
-            if not project_path.exists() or not project_path.is_dir():
+        # 已存在的文件路径集合 (用于去重)
+        existing_paths = set()
+        for res in search_results:
+            if res.get('type') == 'file':
+                # 统一 key 格式
+                existing_paths.add(f"{res['project_id']}:{res['file_path']}")
+
+        keyword_lower = keyword.lower()
+        
+        for project in projects_to_scan:
+            try:
+                project_path = storage_service.get_secure_path(project.storage_key)
+                if not project_path.exists(): continue
+                
+                # 查找文件名匹配
+                md_files = list(project_path.rglob("*.md"))
+                pdf_files = list(project_path.rglob("*.pdf"))
+                
+                for file_path in md_files + pdf_files:
+                    if "_assets" in file_path.parts: continue
+                    
+                    if keyword_lower in file_path.name.lower():
+                        rel_path = str(file_path.relative_to(project_path))
+                        unique_key = f"{project.id}:{rel_path}"
+                        
+                        if unique_key not in existing_paths:
+                            search_results.append({
+                                "type": "file",
+                                "project_id": project.id,
+                                "project_name": project.name,
+                                "file_path": rel_path,
+                                "file_name": file_path.name,
+                                "match_type": "文件名匹配"
+                            })
+                            existing_paths.add(unique_key)
+            except Exception:
                 continue
 
-            # 查找所有 .md 和 .pdf 文件
-            md_files = list(project_path.rglob("*.md"))
-            pdf_files = list(project_path.rglob("*.pdf"))
-            all_files = md_files + pdf_files
+        return success_response(data=search_results[:100])
+    
+    except Exception as e:
+        logger.error(f"Search API error: {e}")
+        return success_response(data=[], message="搜索服务暂时不可用")
 
-            for file_path in all_files:
-                # 跳过 _assets 目录中的文件
-                if "_assets" in file_path.parts:
+
+async def rebuild_index_task(db: AsyncSession):
+    """后台任务：重建索引"""
+    logger.info("Starting index rebuild...")
+    try:
+        # 获取所有项目
+        result = await db.execute(select(Project).where(Project.status == 1))
+        projects = result.scalars().all()
+        
+        documents = []
+        for project in projects:
+            try:
+                # 遍历项目文件
+                project_root = storage_service.get_secure_path(project.storage_key)
+                if not project_root.exists():
                     continue
-
-                try:
-                    # 获取相对路径
-                    relative_path = str(file_path.relative_to(project_path))
-
-                    # 获取文件名（PDF保留扩展名，MD去掉扩展名）
-                    if file_path.suffix.lower() == '.pdf':
-                        file_name = file_path.name  # PDF保留完整文件名
-                    else:
-                        file_name = file_path.stem  # MD去掉扩展名
-
-                    # 检查关键词是否在文件名或路径中
-                    if keyword_lower in file_name.lower() or keyword_lower in relative_path.lower():
-                        search_results.append({
-                            "type": "file",
+                    
+                # 查找所有 .md 文件
+                md_files = list(project_root.rglob("*.md"))
+                
+                for file_path in md_files:
+                    if "_assets" in file_path.parts:
+                        continue
+                        
+                    try:
+                        content = await storage_service.read_file(file_path)
+                        relative_path = str(file_path.relative_to(project_root))
+                        
+                        documents.append({
                             "project_id": project.id,
-                            "project_name": project.name,
-                            "file_path": relative_path,
-                            "file_name": file_name,
-                            "match_type": "文件",
+                            "path": relative_path,
+                            "title": file_path.stem,
+                            "content": content
                         })
+                    except Exception:
+                        continue
+            except Exception as e:
+                logger.error(f"Error processing project {project.id}: {e}")
+                continue
+        
+        # 批量写入索引
+        import asyncio
+        loop = asyncio.get_running_loop()
+        await loop.run_in_executor(None, search_service.rebuild_index_sync, documents)
+        logger.info(f"Index rebuild completed. Indexed {len(documents)} documents.")
+        
+    except Exception as e:
+        logger.error(f"Index rebuild failed: {e}")
 
-                except Exception:
-                    # 忽略无法处理的文件
-                    continue
 
-        except Exception:
-            # 忽略无法遍历的目录
-            continue
-
-    # 限制返回结果数量
-    search_results = search_results[:100]
-
-    return success_response(data=search_results, message=f"找到 {len(search_results)} 个结果")
+@router.post("/rebuild-index", response_model=dict)
+async def rebuild_index(
+    background_tasks: BackgroundTasks,
+    current_user: User = Depends(get_current_user),
+    db: AsyncSession = Depends(get_db)
+):
+    """
+    重建搜索索引 (仅限超级管理员)
+    """
+    if not current_user.is_superuser:
+        raise HTTPException(status_code=403, detail="权限不足")
+        
+    background_tasks.add_task(rebuild_index_task, db)
+    
+    return success_response(message="索引重建任务已启动")
\ No newline at end of file
diff --git a/backend/app/schemas/notification.py b/backend/app/schemas/notification.py
index f3acabe..2bdd199 100644
--- a/backend/app/schemas/notification.py
+++ b/backend/app/schemas/notification.py
@@ -2,7 +2,7 @@
 通知相关的 Pydantic Schema
 """
 from pydantic import BaseModel, Field
-from typing import Optional, List
+from typing import Optional, List, Union
 from datetime import datetime
 
 
@@ -19,14 +19,14 @@ class NotificationCreate(NotificationBase):
 
 
 class NotificationUpdate(BaseModel):
-    is_read: Optional[int] = None
+    is_read: Optional[bool] = None
 
 
 class NotificationResponse(NotificationBase):
-    id: int
+    id: Union[str, int]
     user_id: int
-    is_read: int
-    created_at: datetime
+    is_read: bool
+    created_at: Union[datetime, float]  # Redis returns float timestamp
     read_at: Optional[datetime] = None
 
     class Config:
@@ -34,4 +34,4 @@ class NotificationResponse(NotificationBase):
 
 
 class UnreadCountResponse(BaseModel):
-    unread_count: int
+    unread_count: int
\ No newline at end of file
diff --git a/backend/app/services/notification_service.py b/backend/app/services/notification_service.py
index 0c21536..73982aa 100644
--- a/backend/app/services/notification_service.py
+++ b/backend/app/services/notification_service.py
@@ -1,13 +1,25 @@
 import logging
+import json
+import time
+import uuid
 from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy import select, update, insert
-from app.models.notification import Notification
+from sqlalchemy import select
 from app.models.project import ProjectMember
-from typing import List, Optional
+from app.core.redis_client import get_redis
+from typing import List, Optional, Dict, Any
 
 logger = logging.getLogger(__name__)
 
 class NotificationService:
+    # 通知过期时间：14天 (秒)
+    EXPIRATION_SECONDS = 14 * 24 * 60 * 60
+    
+    def _get_order_key(self, user_id: int) -> str:
+        return f"notifications:order:{user_id}"
+        
+    def _get_content_key(self, user_id: int) -> str:
+        return f"notifications:content:{user_id}"
+
     async def create_notification(
         self,
         db: AsyncSession,
@@ -17,19 +29,41 @@ class NotificationService:
         type: str = "info",
         category: str = "system",
         link: str = None
-    ) -> Notification:
-        """创建单条通知"""
-        db_notification = Notification(
-            user_id=user_id,
-            title=title,
-            content=content,
-            type=type,
-            category=category,
-            link=link
-        )
-        db.add(db_notification)
-        await db.flush()
-        return db_notification
+    ) -> Dict[str, Any]:
+        """创建单条通知 (写入 Redis)"""
+        redis = get_redis()
+        if not redis:
+            return None
+
+        timestamp = time.time()
+        notification_id = str(uuid.uuid4())
+        
+        notification_data = {
+            "id": notification_id,
+            "user_id": user_id,
+            "title": title,
+            "content": content,
+            "type": type,
+            "category": category,
+            "link": link,
+            "is_read": False,
+            "created_at": timestamp
+        }
+        
+        json_data = json.dumps(notification_data, ensure_ascii=False)
+        order_key = self._get_order_key(user_id)
+        content_key = self._get_content_key(user_id)
+        
+        async with redis.pipeline() as pipe:
+            pipe.hset(content_key, notification_id, json_data)
+            pipe.zadd(order_key, {notification_id: timestamp})
+            min_score = timestamp - self.EXPIRATION_SECONDS
+            pipe.zremrangebyscore(order_key, "-inf", min_score)
+            pipe.expire(order_key, self.EXPIRATION_SECONDS + 86400)
+            pipe.expire(content_key, self.EXPIRATION_SECONDS + 86400)
+            await pipe.execute()
+        
+        return notification_data
 
     async def broadcast_system_notification(
         self,
@@ -40,17 +74,37 @@ class NotificationService:
         link: str = None
     ):
         """向指定多个用户发送系统通知"""
-        for uid in user_ids:
-            db_notification = Notification(
-                user_id=uid,
-                title=title,
-                content=content,
-                type="info",
-                category="system",
-                link=link
-            )
-            db.add(db_notification)
-        await db.flush()
+        redis = get_redis()
+        if not redis:
+            return
+
+        timestamp = time.time()
+        
+        async with redis.pipeline() as pipe:
+            for uid in user_ids:
+                notification_id = str(uuid.uuid4())
+                notification_data = {
+                    "id": notification_id,
+                    "user_id": uid,
+                    "title": title,
+                    "content": content,
+                    "type": "info",
+                    "category": "system",
+                    "link": link,
+                    "is_read": False,
+                    "created_at": timestamp
+                }
+                json_data = json.dumps(notification_data, ensure_ascii=False)
+                
+                order_key = self._get_order_key(uid)
+                content_key = self._get_content_key(uid)
+                
+                pipe.hset(content_key, notification_id, json_data)
+                pipe.zadd(order_key, {notification_id: timestamp})
+                pipe.expire(order_key, self.EXPIRATION_SECONDS + 86400)
+                pipe.expire(content_key, self.EXPIRATION_SECONDS + 86400)
+            
+            await pipe.execute()
 
     async def notify_project_members(
         self,
@@ -62,7 +116,6 @@ class NotificationService:
         link: str = None,
         category: str = "project"
     ):
-        """通知项目中除指定用户外的所有成员"""
         result = await db.execute(
             select(ProjectMember.user_id).where(
                 ProjectMember.project_id == project_id,
@@ -71,20 +124,126 @@ class NotificationService:
         )
         member_ids = result.scalars().all()
         
-        logger.info(f"Notifying members of project {project_id}. Found {len(member_ids)} members to notify (excluding user {exclude_user_id}).")
-        
         if member_ids:
-            for uid in member_ids:
-                db_notification = Notification(
-                    user_id=uid,
-                    title=title,
-                    content=content,
-                    type="info",
-                    category=category,
-                    link=link
-                )
-                db.add(db_notification)
-            await db.flush()
+            await self.broadcast_system_notification(
+                db, 
+                title=title, 
+                content=content, 
+                user_ids=member_ids, 
+                link=link
+            )
 
+    async def get_user_notifications(
+        self, 
+        user_id: int, 
+        limit: int = 50, 
+        skip: int = 0
+    ) -> List[Dict[str, Any]]:
+        """获取用户通知列表"""
+        redis = get_redis()
+        if not redis:
+            return []
+            
+        order_key = self._get_order_key(user_id)
+        content_key = self._get_content_key(user_id)
+        
+        ids = await redis.zrevrange(order_key, skip, skip + limit - 1)
+        if not ids:
+            return []
+            
+        json_strings = await redis.hmget(content_key, ids)
+        
+        notifications = []
+        ids_to_remove = []
+        
+        for i, json_str in enumerate(json_strings):
+            if json_str:
+                try:
+                    notifications.append(json.loads(json_str))
+                except:
+                    continue
+            else:
+                ids_to_remove.append(ids[i])
+        
+        if ids_to_remove:
+            await redis.zrem(order_key, *ids_to_remove)
+            
+        return notifications
 
-notification_service = NotificationService()
+    async def get_unread_count(self, user_id: int) -> int:
+        """获取未读通知数量"""
+        redis = get_redis()
+        if not redis:
+            return 0
+            
+        content_key = self._get_content_key(user_id)
+        all_jsons = await redis.hvals(content_key)
+        count = 0
+        for js in all_jsons:
+            try:
+                if js:
+                    data = json.loads(js)
+                    if not data.get('is_read'):
+                        count += 1
+            except:
+                pass
+        return count
+
+    async def mark_read(self, user_id: int, notification_id: str):
+        """标记已读"""
+        redis = get_redis()
+        if not redis:
+            return
+            
+        content_key = self._get_content_key(user_id)
+        
+        json_str = await redis.hget(content_key, notification_id)
+        if json_str:
+            try:
+                data = json.loads(json_str)
+                data['is_read'] = True
+                await redis.hset(content_key, notification_id, json.dumps(data, ensure_ascii=False))
+            except:
+                pass
+
+    async def mark_all_read(self, user_id: int):
+        """标记所有已读"""
+        redis = get_redis()
+        if not redis:
+            return
+            
+        order_key = self._get_order_key(user_id)
+        content_key = self._get_content_key(user_id)
+        
+        ids = await redis.zrange(order_key, 0, -1)
+        if not ids:
+            return
+            
+        json_strings = await redis.hmget(content_key, ids)
+        
+        updates = {}
+        for i, json_str in enumerate(json_strings):
+            if json_str:
+                try:
+                    data = json.loads(json_str)
+                    if not data.get('is_read'):
+                        data['is_read'] = True
+                        updates[ids[i]] = json.dumps(data, ensure_ascii=False)
+                except:
+                    pass
+        
+        if updates:
+            await redis.hset(content_key, mapping=updates)
+
+    async def delete_notification(self, user_id: int, notification_id: str):
+        redis = get_redis()
+        if not redis:
+            return
+            
+        order_key = self._get_order_key(user_id)
+        content_key = self._get_content_key(user_id)
+        
+        await redis.zrem(order_key, notification_id)
+        await redis.hdel(content_key, notification_id)
+
+notification_service = NotificationService()
\ No newline at end of file
diff --git a/backend/app/services/search_service.py b/backend/app/services/search_service.py
new file mode 100644
index 0000000..b864439
--- /dev/null
+++ b/backend/app/services/search_service.py
@@ -0,0 +1,220 @@
+import os
+import shutil
+import asyncio
+import logging
+from pathlib import Path
+from typing import List, Dict, Any, Optional
+from whoosh import index
+from whoosh.fields import Schema, TEXT, ID, DATETIME
+from whoosh.qparser import QueryParser, MultifieldParser
+from whoosh.analysis import Tokenizer, Token
+from whoosh.highlight import HtmlFormatter
+import jieba
+
+from app.core.config import settings
+
+logger = logging.getLogger(__name__)
+
+# 定义中文分词器
+class ChineseTokenizer(Tokenizer):
+    def __call__(self, value, positions=False, chars=False, keeporiginal=False, removestops=True, start_pos=0, start_char=0, mode='', **kwargs):
+        t = Token(positions, chars, removestops=removestops, mode=mode, **kwargs)
+        # cut_for_search returns generator, need to list if iterating repeatedly? 
+        # Tokenizer expects yield Token.
+        try:
+            seglist = jieba.cut_for_search(value)
+            for w in seglist:
+                t.original = t.text = w
+                t.boost = 1.0
+                if positions:
+                    t.pos = start_pos
+                    start_pos += 1
+                if chars:
+                    t.startchar = start_char
+                    t.endchar = start_char + len(w)
+                    start_char += len(w)
+                yield t
+        except Exception as e:
+            logger.error(f"Jieba tokenization error: {e}")
+
+def ChineseAnalyzer():
+    return ChineseTokenizer()
+
+class SearchService:
+    def __init__(self):
+        # 索引存储路径 (使用配置文件中的存储根目录)
+        storage_root = Path(settings.STORAGE_ROOT)
+        # 如果是相对路径，转换为绝对路径 (相对于 backend 根目录，这里假设 settings 已经处理好或者我们手动处理)
+        # settings.STORAGE_ROOT 默认为 /data/...
+        # 本地开发时可能是 ./storage
+        if not storage_root.is_absolute():
+             backend_dir = Path(__file__).parent.parent.parent
+             storage_root = (backend_dir / storage_root).resolve()
+             
+        self.index_dir = storage_root / "search_index"
+        
+        try:
+            self.index_dir.mkdir(parents=True, exist_ok=True)
+        except Exception as e:
+            logger.error(f"Failed to create search index directory: {e}")
+        
+        self.schema = Schema(
+            project_id=ID(stored=True),
+            path=ID(unique=True, stored=True),
+            title=TEXT(stored=True, analyzer=ChineseAnalyzer()),
+            content=TEXT(stored=True, analyzer=ChineseAnalyzer())
+        )
+        
+        self.ix = None
+        try:
+            self._load_or_create_index()
+        except Exception as e:
+            logger.error(f"Failed to initialize search index: {e}")
+
+    def _load_or_create_index(self):
+        # 检查是否包含索引文件
+        if index.exists_in(str(self.index_dir)):
+            try:
+                self.ix = index.open_dir(str(self.index_dir))
+            except Exception as e:
+                logger.warning(f"Failed to open index, trying to recreate: {e}")
+                # 如果打开失败（例如损坏），尝试重建
+                shutil.rmtree(str(self.index_dir))
+                self.index_dir.mkdir(parents=True, exist_ok=True)
+                self.ix = index.create_in(str(self.index_dir), self.schema)
+        else:
+            self.ix = index.create_in(str(self.index_dir), self.schema)
+
+    def _add_document_sync(self, project_id: str, path: str, title: str, content: str):
+        if not self.ix:
+            return
+        try:
+            writer = self.ix.writer()
+            writer.update_document(
+                project_id=str(project_id),
+                path=path,
+                title=title,
+                content=content
+            )
+            writer.commit()
+        except Exception as e:
+            logger.error(f"Failed to add document to index: {e}")
+            # 如果是 LockError，可能需要清理锁? 暂时忽略
+
+    async def add_document(self, project_id: str, path: str, title: str, content: str):
+        """添加或更新文档索引 (Async)"""
+        loop = asyncio.get_running_loop()
+        await loop.run_in_executor(None, self._add_document_sync, project_id, path, title, content)
+
+    def _delete_document_sync(self, unique_path: str):
+        if not self.ix:
+            return
+        try:
+            writer = self.ix.writer()
+            writer.delete_by_term('path', unique_path)
+            writer.commit()
+        except Exception as e:
+            logger.error(f"Failed to delete document from index: {e}")
+
+    async def delete_document(self, project_id: str, path: str):
+        """删除文档索引 (Async)"""
+        unique_path = f"{project_id}:{path}"
+        loop = asyncio.get_running_loop()
+        await loop.run_in_executor(None, self._delete_document_sync, unique_path)
+
+    def _delete_project_documents_sync(self, project_id: str):
+        if not self.ix:
+            return
+        try:
+            writer = self.ix.writer()
+            writer.delete_by_term('project_id', str(project_id))
+            writer.commit()
+        except Exception as e:
+            logger.error(f"Failed to delete project documents: {e}")
+
+    async def delete_project_documents(self, project_id: str):
+        """删除项目下的所有文档索引 (Async)"""
+        loop = asyncio.get_running_loop()
+        await loop.run_in_executor(None, self._delete_project_documents_sync, project_id)
+
+    def _search_sync(self, keyword: str, project_id: Optional[str] = None, limit: int = 20):
+        if not keyword or not self.ix:
+            return []
+            
+        try:
+            with self.ix.searcher() as searcher:
+                parser = MultifieldParser(["title", "content"], schema=self.ix.schema)
+                query = parser.parse(keyword)
+                
+                filter_query = None
+                if project_id:
+                    filter_parser = QueryParser("project_id", schema=self.ix.schema)
+                    filter_query = filter_parser.parse(str(project_id))
+                
+                results = searcher.search(query, filter=filter_query, limit=limit)
+                results.formatter = HtmlFormatter(tagname="mark", classname="search-highlight", termclass="search-term")
+                
+                search_results = []
+                for hit in results:
+                    # 提取原始路径 (去掉 project_id 前缀)
+                    full_path = hit.get("path", "")
+                    if ":" in full_path:
+                        _, real_path = full_path.split(":", 1)
+                    else:
+                        real_path = full_path
+                        
+                    # 安全获取高亮
+                    try:
+                        highlights = hit.highlights("content") or hit.highlights("title") or hit.get("title", "")
+                    except:
+                        highlights = hit.get("title", "")
+
+                    search_results.append({
+                        "project_id": hit.get("project_id"),
+                        "path": real_path,
+                        "title": hit.get("title"),
+                        "highlights": highlights,
+                        "score": hit.score
+                    })
+                    
+                return search_results
+        except Exception as e:
+            logger.error(f"Search failed: {e}")
+            # 返回空列表而不是抛出异常
+            return []
+
+    async def search(self, keyword: str, project_id: Optional[str] = None, limit: int = 20):
+        """搜索文档 (Async)"""
+        loop = asyncio.get_running_loop()
+        return await loop.run_in_executor(None, self._search_sync, keyword, project_id, limit)
+
+    async def update_doc(self, project_id: int, path: str, title: str, content: str):
+        """添加或更新文档 (对外接口)"""
+        unique_path = f"{project_id}:{path}"
+        await self.add_document(str(project_id), unique_path, title, content)
+
+    async def remove_doc(self, project_id: int, path: str):
+        """删除文档 (对外接口)"""
+        await self.delete_document(str(project_id), path)
+        
+    def rebuild_index_sync(self, documents: List[Dict]):
+        """同步重建索引"""
+        if not self.ix:
+            return
+            
+        try:
+            writer = self.ix.writer()
+            # 这里的 documents 必须包含 project_id, path, title, content
+            for doc in documents:
+                unique_path = f"{doc['project_id']}:{doc['path']}"
+                writer.update_document(
+                    project_id=str(doc['project_id']),
+                    path=unique_path,
+                    title=doc['title'],
+                    content=doc['content']
+                )
+            writer.commit()
+        except Exception as e:
+            logger.error(f"Rebuild index failed: {e}")
+
+search_service = SearchService()
diff --git a/backend/requirements.txt b/backend/requirements.txt
index cdc45e7..5c21ed7 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -18,6 +18,7 @@ greenlet==3.2.4
 h11==0.16.0
 httptools==0.7.1
 idna==3.11
+jieba==0.42.1
 loguru==0.7.2
 Mako==1.3.10
 MarkupSafe==3.0.3
@@ -43,3 +44,4 @@ uvicorn==0.27.0
 uvloop==0.22.1
 watchfiles==1.1.1
 websockets==15.0.1
+Whoosh==2.7.4
\ No newline at end of file
diff --git a/frontend/package.json b/frontend/package.json
index c2aa77e..70ee76d 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -22,9 +22,12 @@
     "axios": "^1.6.2",
     "bytemd": "^1.22.0",
     "dayjs": "^1.11.10",
+    "github-slugger": "^2.0.0",
+    "mark.js": "^8.11.1",
     "pdfjs-dist": "5.4.296",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
+    "react-highlight-words": "^0.21.0",
     "react-markdown": "^9.0.1",
     "react-pdf": "^10.2.0",
     "react-router-dom": "^6.20.1",
diff --git a/frontend/src/api/search.js b/frontend/src/api/search.js
index 894b99e..7aeb037 100644
--- a/frontend/src/api/search.js
+++ b/frontend/src/api/search.js
@@ -5,11 +5,23 @@ import request from '@/utils/request'
 
 /**
  * 搜索文档
+ * @param {string} keyword - 搜索关键词
+ * @param {string} project_id - 项目ID (可选，限制搜索范围)
  */
-export function searchDocuments(keyword) {
+export function searchDocuments(keyword, project_id) {
   return request({
     url: '/search/documents',
     method: 'get',
-    params: { keyword },
+    params: { keyword, project_id },
+  })
+}
+
+/**
+ * 重建搜索索引 (仅管理员)
+ */
+export function rebuildIndex() {
+  return request({
+    url: '/search/rebuild-index',
+    method: 'post',
   })
 }
diff --git a/frontend/src/components/MainLayout/AppHeader.jsx b/frontend/src/components/MainLayout/AppHeader.jsx
index 48bfefe..3c22038 100644
--- a/frontend/src/components/MainLayout/AppHeader.jsx
+++ b/frontend/src/components/MainLayout/AppHeader.jsx
@@ -208,6 +208,7 @@ function AppHeader({ collapsed, onToggle }) {
       <div className="header-left">
         {/* Logo 区域 */}
         <div className="header-logo">
+          <img src="/favicon.svg" alt="logo" style={{ width: 32, height: 32, marginRight: 8 }} />
           <h2 style={{ margin: 0, color: '#1677ff', fontWeight: 'bold' }}>NexDocus</h2>
         </div>
 
diff --git a/frontend/src/index.css b/frontend/src/index.css
index b5c61c9..b0435a7 100644
--- a/frontend/src/index.css
+++ b/frontend/src/index.css
@@ -1,3 +1,7 @@
-@tailwind base;
-@tailwind components;
-@tailwind utilities;
+.search-highlight {
+  background-color: #ffd54f !important;
+  color: black !important;
+  font-weight: bold;
+  padding: 0 2px;
+  border-radius: 2px;
+}
\ No newline at end of file
diff --git a/frontend/src/pages/Dashboard.jsx b/frontend/src/pages/Dashboard.jsx
index 2e7b0c1..34eea89 100644
--- a/frontend/src/pages/Dashboard.jsx
+++ b/frontend/src/pages/Dashboard.jsx
@@ -1,11 +1,13 @@
 import { useState, useEffect } from 'react'
-import { Card, Row, Col, Statistic, Table, Spin } from 'antd'
-import { UserOutlined, ProjectOutlined, FileTextOutlined } from '@ant-design/icons'
+import { Card, Row, Col, Statistic, Table, Spin, Button, Tooltip, message } from 'antd'
+import { UserOutlined, ProjectOutlined, FileTextOutlined, SyncOutlined } from '@ant-design/icons'
 import { getDashboardStats } from '@/api/dashboard'
+import { rebuildIndex } from '@/api/search'
 import Toast from '@/components/Toast/Toast'
 
 function Dashboard() {
   const [loading, setLoading] = useState(true)
+  const [rebuilding, setRebuilding] = useState(false)
   const [stats, setStats] = useState({
     user_count: 0,
     project_count: 0,
@@ -34,6 +36,19 @@ function Dashboard() {
     }
   }
 
+  const handleRebuildIndex = async () => {
+    setRebuilding(true)
+    try {
+      await rebuildIndex()
+      message.success('索引重建任务已启动，请稍后搜索尝试')
+    } catch (error) {
+      console.error('Rebuild index error:', error)
+      message.error('重建索引失败: ' + (error.response?.data?.detail || error.message))
+    } finally {
+      setRebuilding(false)
+    }
+  }
+
   const userColumns = [
     {
       title: '用户名',
@@ -117,7 +132,23 @@ function Dashboard() {
           <Col span={8}>
             <Card>
               <Statistic
-                title="文档总数"
+                title={
+                  <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
+                    <span>文档总数</span>
+                    <Tooltip title="重建全文搜索索引（扫描所有文档）">
+                      <Button 
+                        type="link" 
+                        size="small"
+                        style={{ padding: 0, height: 'auto' }}
+                        icon={<SyncOutlined spin={rebuilding} />} 
+                        onClick={handleRebuildIndex}
+                        disabled={rebuilding}
+                      >
+                        重建索引
+                      </Button>
+                    </Tooltip>
+                  </div>
+                }
                 value={stats.document_count}
                 prefix={<FileTextOutlined />}
                 valueStyle={{ color: '#cf1322' }}
@@ -150,4 +181,4 @@ function Dashboard() {
   )
 }
 
-export default Dashboard
+export default Dashboard
\ No newline at end of file
diff --git a/frontend/src/pages/Document/DocumentPage.jsx b/frontend/src/pages/Document/DocumentPage.jsx
index 190d505..f353826 100644
--- a/frontend/src/pages/Document/DocumentPage.jsx
+++ b/frontend/src/pages/Document/DocumentPage.jsx
@@ -1,22 +1,38 @@
-import { useState, useEffect, useRef } from 'react'
+import { useState, useEffect, useRef, useMemo } from 'react'
 import { useParams, useNavigate, useSearchParams } from 'react-router-dom'
-import { Layout, Menu, Spin, FloatButton, Button, Tooltip, message, Anchor, Modal, Input, Switch, Space, Dropdown } from 'antd'
-import { EditOutlined, VerticalAlignTopOutlined, ShareAltOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, CopyOutlined, LockOutlined, CloudDownloadOutlined, CloudUploadOutlined, DownOutlined } from '@ant-design/icons'
+import { Layout, Menu, Spin, FloatButton, Button, Tooltip, message, Anchor, Modal, Input, Switch, Space, Dropdown, Empty } from 'antd'
+import { EditOutlined, VerticalAlignTopOutlined, ShareAltOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, CopyOutlined, LockOutlined, CloudDownloadOutlined, CloudUploadOutlined, DownOutlined, SearchOutlined } from '@ant-design/icons'
 import ReactMarkdown from 'react-markdown'
 import remarkGfm from 'remark-gfm'
 import rehypeRaw from 'rehype-raw'
 import rehypeSlug from 'rehype-slug'
 import rehypeHighlight from 'rehype-highlight'
 import 'highlight.js/styles/github.css'
+import Highlighter from 'react-highlight-words'
+import GithubSlugger from 'github-slugger'
 import { getProjectTree, getFileContent, getDocumentUrl } from '@/api/file'
 import { gitPull, gitPush, getGitRepos } from '@/api/project'
 import { getProjectShareInfo, updateShareSettings } from '@/api/share'
+import { searchDocuments } from '@/api/search'
 import VirtualPDFViewer from '@/components/PDFViewer/VirtualPDFViewer'
 import Toast from '@/components/Toast/Toast'
 import './DocumentPage.css'
 
 const { Sider, Content } = Layout
 
+// 高亮渲染组件
+const HighlightText = ({ text, keyword }) => {
+  if (!keyword || !text) return text;
+  return (
+    <Highlighter
+      highlightClassName="search-highlight"
+      searchWords={[keyword]}
+      autoEscape={true}
+      textToHighlight={text}
+    />
+  )
+}
+
 function DocumentPage() {
   const { projectId } = useParams()
   const navigate = useNavigate()
@@ -32,13 +48,19 @@ function DocumentPage() {
   const [shareInfo, setShareInfo] = useState(null)
   const [hasPassword, setHasPassword] = useState(false)
   const [password, setPassword] = useState('')
-  const [userRole, setUserRole] = useState('viewer') // 用户角色：owner/admin/editor/viewer
+  const [userRole, setUserRole] = useState('viewer')
   const [pdfViewerVisible, setPdfViewerVisible] = useState(false)
   const [pdfUrl, setPdfUrl] = useState('')
   const [pdfFilename, setPdfFilename] = useState('')
-  const [viewMode, setViewMode] = useState('markdown') // 'markdown' or 'pdf'
+  const [viewMode, setViewMode] = useState('markdown')
   const [gitRepos, setGitRepos] = useState([])
   const [projectName, setProjectName] = useState('')
+  
+  // 搜索相关状态
+  const [searchKeyword, setSearchKeyword] = useState('')
+  const [matchedFilePaths, setMatchedFilePaths] = useState(new Set())
+  const [isSearching, setIsSearching] = useState(false)
+  
   const contentRef = useRef(null)
 
   useEffect(() => {
@@ -51,6 +73,64 @@ function DocumentPage() {
     }
   }, [projectId, userRole])
 
+  // 处理搜索
+  const handleSearch = async (value) => {
+    setSearchKeyword(value)
+    if (!value.trim()) {
+      setMatchedFilePaths(new Set())
+      return
+    }
+
+    setIsSearching(true)
+    try {
+      const res = await searchDocuments(value, projectId)
+      const paths = new Set(res.data.map(item => item.file_path))
+      setMatchedFilePaths(paths)
+      
+      // 自动展开匹配的节点
+      const keysToExpand = new Set(openKeys)
+      res.data.forEach(item => {
+        const parts = item.file_path.split('/')
+        let currentPath = ''
+        for (let i = 0; i < parts.length - 1; i++) {
+          currentPath = currentPath ? `${currentPath}/${parts[i]}` : parts[i]
+          keysToExpand.add(currentPath)
+        }
+      })
+      setOpenKeys(Array.from(keysToExpand))
+    } catch (error) {
+      console.error('Search error:', error)
+    } finally {
+      setIsSearching(false)
+    }
+  }
+
+  // 过滤文件树
+  const filteredTreeData = useMemo(() => {
+    if (!searchKeyword.trim()) return fileTree
+
+    const loop = (data) => {
+      const result = []
+      for (const node of data) {
+        const titleMatch = node.title.toLowerCase().includes(searchKeyword.toLowerCase())
+        const contentMatch = matchedFilePaths.has(node.key)
+        
+        if (node.children) {
+          const children = loop(node.children)
+          if (children.length > 0 || titleMatch) {
+            result.push({ ...node, children })
+          }
+        } else {
+          if (titleMatch || contentMatch) {
+            result.push(node)
+          }
+        }
+      }
+      return result
+    }
+    return loop(fileTree)
+  }, [fileTree, searchKeyword, matchedFilePaths])
+
   const loadGitRepos = async () => {
     try {
       const res = await getGitRepos(projectId)
@@ -75,6 +155,12 @@ function DocumentPage() {
 
       // 检查 URL 是否指定了文件
       const fileParam = searchParams.get('file')
+      const keywordParam = searchParams.get('keyword')
+      
+      if (keywordParam) {
+        handleSearch(keywordParam)
+      }
+
       if (fileParam) {
         setSelectedFile(fileParam)
         
@@ -131,6 +217,9 @@ function DocumentPage() {
   // 转换文件树为菜单项
   const convertTreeToMenuItems = (nodes) => {
     return nodes.map((node) => {
+      // 标题高亮处理 - 取消高亮，仅显示原始标题
+      const titleNode = node.title.replace('.md', '')
+
       if (!node.isLeaf) {
         // 目录
         return {
@@ -143,7 +232,7 @@ function DocumentPage() {
         // Markdown 文件
         return {
           key: node.key,
-          label: node.title.replace('.md', ''),
+          label: titleNode,
           icon: <FileTextOutlined />,
         }
       } else if (node.title && node.title.endsWith('.pdf')) {
@@ -181,6 +270,7 @@ function DocumentPage() {
   // 提取 markdown 标题生成目录
   useEffect(() => {
     if (markdownContent) {
+      const slugger = new GithubSlugger()
       const headings = []
       const lines = markdownContent.split('\n')
 
@@ -189,15 +279,8 @@ function DocumentPage() {
         if (match) {
           const level = match[1].length
           const title = match[2]
-          // 模拟 rehype-slug/github-slugger 的 ID 生成规则
-          const key = title
-            .toLowerCase()
-            .trim()
-            .replace(/\s+/g, '-')                // 空格转连字符
-            .replace(/[^\w\-\u4e00-\u9fa5]+/g, '') // 移除非单词字符(保留中文、数字、字母、下划线、连字符)
-            .replace(/\-\-+/g, '-')              // 合并重复连字符
-            .replace(/^-+/, '')                  // 去除头部连字符
-            .replace(/-+$/, '')                  // 去除尾部连字符
+          // 使用标准的 github-slugger 生成 ID，确保与 rehype-slug 一致
+          const key = slugger.slug(title)
 
           headings.push({
             key: `#${key}`,
@@ -586,7 +669,81 @@ function DocumentPage() {
     }
   }
 
-  const menuItems = convertTreeToMenuItems(fileTree)
+  const menuItems = convertTreeToMenuItems(filteredTreeData)
+
+  // Markdown 内容高亮处理
+  // 使用 components 替换文本节点，但这只对直接文本子节点有效
+  // 对于深层嵌套，我们需要递归或使用 rehype 插件
+  // 这里使用简单组件替换
+  const markdownComponents = useMemo(() => {
+    if (!searchKeyword) {
+      return {
+        a: ({ node, href, children, ...props }) => {
+          const isExternal = href && (href.startsWith('http') || href.startsWith('//'));
+          return (
+            <a
+              href={href}
+              onClick={(e) => handleMarkdownLink(e, href)}
+              target={isExternal ? '_blank' : undefined}
+              rel={isExternal ? 'noopener noreferrer' : undefined}
+              {...props}
+            >
+              {children}
+            </a>
+          );
+        },
+      }
+    }
+
+    // 搜索模式下，尝试高亮
+    // 注意：这可能不完美，但比没有好
+    const highlightRenderer = (Tag) => ({ node, children, ...props }) => {
+      // 如果 children 是字符串，高亮
+      if (typeof children === 'string') {
+        return <Tag {...props}><HighlightText text={children} keyword={searchKeyword} /></Tag>
+      }
+      // 如果是数组，遍历
+      if (Array.isArray(children)) {
+        const newChildren = children.map((child, idx) => {
+          if (typeof child === 'string') {
+            return <HighlightText key={idx} text={child} keyword={searchKeyword} />
+          }
+          return child
+        })
+        return <Tag {...props}>{newChildren}</Tag>
+      }
+      return <Tag {...props}>{children}</Tag>
+    }
+
+    return {
+      a: ({ node, href, children, ...props }) => {
+        const isExternal = href && (href.startsWith('http') || href.startsWith('//'));
+        return (
+          <a
+            href={href}
+            onClick={(e) => handleMarkdownLink(e, href)}
+            target={isExternal ? '_blank' : undefined}
+            rel={isExternal ? 'noopener noreferrer' : undefined}
+            {...props}
+          >
+            {typeof children === 'string' ? <HighlightText text={children} keyword={searchKeyword} /> : children}
+          </a>
+        );
+      },
+      p: highlightRenderer('p'),
+      li: highlightRenderer('li'),
+      h1: highlightRenderer('h1'),
+      h2: highlightRenderer('h2'),
+      h3: highlightRenderer('h3'),
+      h4: highlightRenderer('h4'),
+      h5: highlightRenderer('h5'),
+      h6: highlightRenderer('h6'),
+      span: highlightRenderer('span'),
+      td: highlightRenderer('td'),
+      th: highlightRenderer('th'),
+      div: highlightRenderer('div'),
+    }
+  }, [searchKeyword])
 
   return (
     <div className="project-docs-page">
@@ -623,15 +780,34 @@ function DocumentPage() {
             </div>
           </div>
 
-          <Menu
-            mode="inline"
-            selectedKeys={[selectedFile]}
-            openKeys={openKeys}
-            onOpenChange={setOpenKeys}
-            items={menuItems}
-            onClick={handleMenuClick}
-            className="docs-menu"
-          />
+          {/* 搜索框 */}
+          <div style={{ padding: '12px 16px 4px' }}>
+            <Input.Search
+              placeholder="搜索文档内容..."
+              allowClear
+              value={searchKeyword}
+              onChange={(e) => setSearchKeyword(e.target.value)}
+              onSearch={handleSearch}
+              loading={isSearching}
+              enterButton
+            />
+          </div>
+
+          {filteredTreeData.length > 0 ? (
+            <Menu
+              mode="inline"
+              selectedKeys={[selectedFile]}
+              openKeys={openKeys}
+              onOpenChange={setOpenKeys}
+              items={menuItems}
+              onClick={handleMenuClick}
+              className="docs-menu"
+            />
+          ) : (
+            <div style={{ padding: '20px', textAlign: 'center', color: '#999' }}>
+              <Empty image={Empty.PRESENTED_IMAGE_SIMPLE} description="未找到匹配文档" />
+            </div>
+          )}
         </Sider>
 
         {/* 右侧内容区 */}
@@ -654,22 +830,7 @@ function DocumentPage() {
                   <ReactMarkdown
                     remarkPlugins={[remarkGfm]}
                     rehypePlugins={[rehypeRaw, rehypeSlug, rehypeHighlight]}
-                    components={{
-                      a: ({ node, href, children, ...props }) => {
-                        const isExternal = href && (href.startsWith('http') || href.startsWith('//'));
-                        return (
-                          <a
-                            href={href}
-                            onClick={(e) => handleMarkdownLink(e, href)}
-                            target={isExternal ? '_blank' : undefined}
-                            rel={isExternal ? 'noopener noreferrer' : undefined}
-                            {...props}
-                          >
-                            {children}
-                          </a>
-                        );
-                      },
-                    }}
+                    components={markdownComponents}
                   >
                     {markdownContent}
                   </ReactMarkdown>
@@ -716,7 +877,7 @@ function DocumentPage() {
                       title: (
                         <div style={{ paddingLeft: `${(item.level - 1) * 12}px`, display: 'flex', alignItems: 'center', gap: '4px' }}>
                           <FileTextOutlined style={{ fontSize: '12px', color: '#8c8c8c' }} />
-                          {item.title}
+                          <HighlightText text={item.title} keyword={searchKeyword} />
                         </div>
                       ),
                     }))}
@@ -743,6 +904,7 @@ function DocumentPage() {
       </Layout>
 
       {/* 分享模态框 */}
+      {/* ... keeping the modal ... */}
       <Modal
         title="分享项目"
         open={shareModalVisible}
@@ -793,4 +955,4 @@ function DocumentPage() {
   )
 }
 
-export default DocumentPage
+export default DocumentPage
\ No newline at end of file
diff --git a/frontend/src/pages/Login/Login.jsx b/frontend/src/pages/Login/Login.jsx
index 8e5bd9b..fb6eb91 100644
--- a/frontend/src/pages/Login/Login.jsx
+++ b/frontend/src/pages/Login/Login.jsx
@@ -88,12 +88,10 @@ function Login() {
 
           <div className="intro-section">
             <h1 className="intro-title">
-              团队协作
-              <br />
-              <span className="highlight">文档管理平台</span>
+              团队协作<span className="highlight"> 文档管理平台</span>
             </h1>
             <p className="intro-desc">
-              全流程文档共享，提升团队协作效率的新一代解决方案。
+              全流程文档协作共享，让每一份文档都产生价值。
             </p>
           </div>
 
diff --git a/frontend/src/pages/Preview/PreviewPage.jsx b/frontend/src/pages/Preview/PreviewPage.jsx
index 4b51759..c20149a 100644
--- a/frontend/src/pages/Preview/PreviewPage.jsx
+++ b/frontend/src/pages/Preview/PreviewPage.jsx
@@ -1,7 +1,7 @@
 import { useState, useEffect, useRef, useMemo } from 'react'
-import { useParams } from 'react-router-dom'
-import { Layout, Menu, Spin, FloatButton, Button, Modal, Input, message, Drawer, Anchor } from 'antd'
-import { VerticalAlignTopOutlined, MenuOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, LockOutlined } from '@ant-design/icons'
+import { useParams, useSearchParams } from 'react-router-dom'
+import { Layout, Menu, Spin, FloatButton, Button, Modal, Input, message, Drawer, Anchor, Empty } from 'antd'
+import { VerticalAlignTopOutlined, MenuOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, LockOutlined, SearchOutlined } from '@ant-design/icons'
 import { Viewer } from '@bytemd/react'
 import gfm from '@bytemd/plugin-gfm'
 import highlight from '@bytemd/plugin-highlight'
@@ -11,14 +11,32 @@ import gemoji from '@bytemd/plugin-gemoji'
 import 'bytemd/dist/index.css'
 import rehypeSlug from 'rehype-slug'
 import 'highlight.js/styles/github.css'
+import Mark from 'mark.js'
+import Highlighter from 'react-highlight-words'
+import GithubSlugger from 'github-slugger'
 import { getPreviewInfo, getPreviewTree, getPreviewFile, verifyAccessPassword, getPreviewDocumentUrl } from '@/api/share'
+import { searchDocuments } from '@/api/search'
 import VirtualPDFViewer from '@/components/PDFViewer/VirtualPDFViewer'
 import './PreviewPage.css'
 
 const { Sider, Content } = Layout
 
+// 高亮组件 (用于 Tree)
+const HighlightText = ({ text, keyword }) => {
+  if (!keyword || !text) return text;
+  return (
+    <Highlighter
+      highlightClassName="search-highlight"
+      searchWords={[keyword]}
+      autoEscape={true}
+      textToHighlight={text}
+    />
+  )
+}
+
 function PreviewPage() {
   const { projectId } = useParams()
+  const [searchParams] = useSearchParams()
   const [projectInfo, setProjectInfo] = useState(null)
   const [fileTree, setFileTree] = useState([])
   const [selectedFile, setSelectedFile] = useState('')
@@ -29,15 +47,22 @@ function PreviewPage() {
   const [tocItems, setTocItems] = useState([])
   const [passwordModalVisible, setPasswordModalVisible] = useState(false)
   const [password, setPassword] = useState('')
-  const [accessPassword, setAccessPassword] = useState(null) // 已验证的密码
+  const [accessPassword, setAccessPassword] = useState(null)
   const [siderCollapsed, setSiderCollapsed] = useState(false)
   const [mobileDrawerVisible, setMobileDrawerVisible] = useState(false)
   const [isMobile, setIsMobile] = useState(false)
   const [pdfViewerVisible, setPdfViewerVisible] = useState(false)
   const [pdfUrl, setPdfUrl] = useState('')
   const [pdfFilename, setPdfFilename] = useState('')
-  const [viewMode, setViewMode] = useState('markdown') // 'markdown' or 'pdf'
+  const [viewMode, setViewMode] = useState('markdown')
+  
+  // 搜索相关
+  const [searchKeyword, setSearchKeyword] = useState('')
+  const [matchedFilePaths, setMatchedFilePaths] = useState(new Set())
+  const [isSearching, setIsSearching] = useState(false)
+
   const contentRef = useRef(null)
+  const viewerRef = useRef(null)
 
   // ByteMD 插件配置
   const plugins = useMemo(() => [
@@ -51,6 +76,22 @@ function PreviewPage() {
     }
   ], [])
 
+  // mark.js 高亮
+  useEffect(() => {
+    if (viewerRef.current && viewMode === 'markdown') {
+      const instance = new Mark(viewerRef.current)
+      instance.unmark()
+      
+      if (searchKeyword.trim()) {
+        instance.mark(searchKeyword, {
+          element: 'span',
+          className: 'search-highlight',
+          exclude: ['pre', 'code', '.toc-content']
+        })
+      }
+    }
+  }, [markdownContent, searchKeyword, viewMode])
+
   // 检测是否为移动设备
   useEffect(() => {
     const checkMobile = () => {
@@ -73,10 +114,8 @@ function PreviewPage() {
       setProjectInfo(info)
 
       if (info.has_password) {
-        // 需要密码验证
         setPasswordModalVisible(true)
       } else {
-        // 无需密码，直接加载文档树
         loadFileTree()
       }
     } catch (error) {
@@ -110,9 +149,52 @@ function PreviewPage() {
       const tree = res.data || []
       setFileTree(tree)
 
-      // 默认打开 README.md
       const readmeNode = findReadme(tree)
-      if (readmeNode) {
+      
+      // Check query params
+      const fileParam = searchParams.get('file')
+      const keywordParam = searchParams.get('keyword')
+
+      if (keywordParam) {
+        handleSearch(keywordParam)
+      }
+
+      if (fileParam) {
+        // Deep link to file
+        if (fileParam.toLowerCase().endsWith('.pdf')) {
+           let url = getPreviewDocumentUrl(projectId, fileParam)
+           // ... params logic repeated from handleMenuClick ...
+           // Simplify: just call logic or set state
+           // Since we need token/password logic, let's reuse handleMenuClick logic if possible or copy it.
+           // For simplicity, just set selection and let user click? No, auto load.
+           
+           // Copy logic for PDF url construction
+           const params = []
+           if (pwd || accessPassword) params.push(`access_pass=${encodeURIComponent(pwd || accessPassword)}`)
+           const token = localStorage.getItem('access_token')
+           if (token) params.push(`token=${encodeURIComponent(token)}`)
+           if (params.length > 0) url += `?${params.join('&')}`
+           
+           setSelectedFile(fileParam)
+           setPdfUrl(url)
+           setPdfFilename(fileParam.split('/').pop())
+           setViewMode('pdf')
+        } else {
+           setSelectedFile(fileParam)
+           loadMarkdown(fileParam, pwd || accessPassword)
+        }
+        
+        // Expand tree to file
+        const parts = fileParam.split('/')
+        const allParentPaths = []
+        let currentPath = ''
+        for (let i = 0; i < parts.length - 1; i++) {
+          currentPath = currentPath ? `${currentPath}/${parts[i]}` : parts[i]
+          allParentPaths.push(currentPath)
+        }
+        setOpenKeys(prev => [...new Set([...prev, ...allParentPaths])])
+
+      } else if (readmeNode) {
         setSelectedFile(readmeNode.key)
         loadMarkdown(readmeNode.key, pwd || accessPassword)
       }
@@ -125,7 +207,64 @@ function PreviewPage() {
     }
   }
 
-  // 查找根目录的 README.md
+  // 搜索处理
+  const handleSearch = async (value) => {
+    setSearchKeyword(value)
+    if (!value.trim()) {
+      setMatchedFilePaths(new Set())
+      return
+    }
+
+    setIsSearching(true)
+    try {
+      const res = await searchDocuments(value, projectId)
+      const paths = new Set(res.data.map(item => item.file_path))
+      setMatchedFilePaths(paths)
+      
+      // 自动展开匹配的节点 (Assuming this comment might be there or not, better context: keysToExpand)
+      const keysToExpand = new Set(openKeys)
+      res.data.forEach(item => {
+        const parts = item.file_path.split('/')
+        let currentPath = ''
+        for (let i = 0; i < parts.length - 1; i++) {
+          currentPath = currentPath ? `${currentPath}/${parts[i]}` : parts[i]
+          keysToExpand.add(currentPath)
+        }
+      })
+      setOpenKeys(Array.from(keysToExpand))
+    } catch (error) {
+      console.error('Search error:', error)
+    } finally {
+      setIsSearching(false)
+    }
+  }
+
+  // 过滤树
+  const filteredTreeData = useMemo(() => {
+    if (!searchKeyword.trim()) return fileTree
+
+    const loop = (data) => {
+      const result = []
+      for (const node of data) {
+        const titleMatch = node.title.toLowerCase().includes(searchKeyword.toLowerCase())
+        const contentMatch = matchedFilePaths.has(node.key)
+        
+        if (node.children) {
+          const children = loop(node.children)
+          if (children.length > 0 || titleMatch) {
+            result.push({ ...node, children })
+          }
+        } else {
+          if (titleMatch || contentMatch) {
+            result.push(node)
+          }
+        }
+      }
+      return result
+    }
+    return loop(fileTree)
+  }, [fileTree, searchKeyword, matchedFilePaths])
+
   const findReadme = (nodes) => {
     for (const node of nodes) {
       if (node.title === 'README.md' && node.isLeaf) {
@@ -135,9 +274,10 @@ function PreviewPage() {
     return null
   }
 
-  // 转换文件树为菜单项
   const convertTreeToMenuItems = (nodes) => {
     return nodes.map((node) => {
+      const labelNode = node.title.replace('.md', '')
+      
       if (!node.isLeaf) {
         return {
           key: node.key,
@@ -148,7 +288,7 @@ function PreviewPage() {
       } else if (node.title && node.title.endsWith('.md')) {
         return {
           key: node.key,
-          label: node.title.replace('.md', ''),
+          label: labelNode,
           icon: <FileTextOutlined />,
         }
       } else if (node.title && node.title.endsWith('.pdf')) {
@@ -162,7 +302,6 @@ function PreviewPage() {
     }).filter(Boolean)
   }
 
-  // 加载 markdown 文件
   const loadMarkdown = async (filePath, pwd = null) => {
     setLoading(true)
     setTocItems([])
@@ -170,12 +309,10 @@ function PreviewPage() {
       const res = await getPreviewFile(projectId, filePath, pwd || accessPassword)
       setMarkdownContent(res.data?.content || '')
 
-      // 移动端自动关闭侧边栏
       if (isMobile) {
         setMobileDrawerVisible(false)
       }
 
-      // 滚动到顶部
       if (contentRef.current) {
         contentRef.current.scrollTo({ top: 0, behavior: 'smooth' })
       }
@@ -192,9 +329,9 @@ function PreviewPage() {
     }
   }
 
-  // 提取 markdown 标题生成目录
   useEffect(() => {
     if (markdownContent) {
+      const slugger = new GithubSlugger()
       const headings = []
       const lines = markdownContent.split('\n')
 
@@ -203,7 +340,8 @@ function PreviewPage() {
         if (match) {
           const level = match[1].length
           const title = match[2]
-          const key = title.toLowerCase().replace(/[^a-z0-9\u4e00-\u9fa5]+/g, '-')
+          // 使用标准的 github-slugger 生成 ID，确保与 rehype-slug 一致
+          const key = slugger.slug(title)
 
           headings.push({
             key: `#${key}`,
@@ -217,7 +355,7 @@ function PreviewPage() {
       setTocItems(headings)
     }
   }, [markdownContent])
-  // 解析相对路径
+
   const resolveRelativePath = (currentPath, relativePath) => {
     if (relativePath.startsWith('/')) {
       return relativePath.substring(1)
@@ -240,7 +378,6 @@ function PreviewPage() {
     return dirParts.join('/')
   }
 
-  // 处理 markdown 内部链接点击
   const handleMarkdownLink = (e, href) => {
     if (!href || href.startsWith('http') || href.startsWith('//') || href.startsWith('#')) {
       return
@@ -257,7 +394,6 @@ function PreviewPage() {
     try {
       decodedHref = decodeURIComponent(href)
     } catch (err) {
-      // ignore
     }
 
     const targetPath = resolveRelativePath(selectedFile, decodedHref)
@@ -278,7 +414,6 @@ function PreviewPage() {
     handleMenuClick({ key: targetPath })
   }
 
-  // 处理内容区域点击（委托处理链接点击）
   const handleContentClick = (e) => {
     const target = e.target.closest('a')
     if (target) {
@@ -289,22 +424,17 @@ function PreviewPage() {
     }
   }
 
-  // 处理菜单点击
   const handleMenuClick = ({ key }) => {
     setSelectedFile(key)
 
-    // 检查是否是PDF文件
     if (key.toLowerCase().endsWith('.pdf')) {
-      // 显示PDF - 使用预览API，添加必要的参数
       let url = getPreviewDocumentUrl(projectId, key)
       const params = []
 
-      // 如果有密码，添加密码参数
       if (accessPassword) {
         params.push(`access_pass=${encodeURIComponent(accessPassword)}`)
       }
 
-      // 如果用户已登录（私密项目需要），添加token参数
       const token = localStorage.getItem('access_token')
       if (token) {
         params.push(`token=${encodeURIComponent(token)}`)
@@ -318,39 +448,16 @@ function PreviewPage() {
       setPdfFilename(key.split('/').pop())
       setViewMode('pdf')
     } else {
-      // 加载Markdown文件
       setViewMode('markdown')
       loadMarkdown(key)
     }
   }
 
-  const menuItems = convertTreeToMenuItems(fileTree)
-
-  // 侧边栏内容
-  const SiderContent = () => (
-    <>
-      <div className="preview-sider-header">
-        <h2>{projectInfo?.name || '项目预览'}</h2>
-        {projectInfo?.description && (
-          <p className="preview-project-desc">{projectInfo.description}</p>
-        )}
-      </div>
-      <Menu
-        mode="inline"
-        selectedKeys={[selectedFile]}
-        openKeys={openKeys}
-        onOpenChange={setOpenKeys}
-        items={menuItems}
-        onClick={handleMenuClick}
-        className="preview-menu"
-      />
-    </>
-  )
+  const menuItems = convertTreeToMenuItems(filteredTreeData)
 
   return (
     <div className="preview-page">
       <Layout className="preview-layout">
-        {/* 移动端使用 Drawer，桌面端使用 Sider */}
         {isMobile ? (
           <>
             <Button
@@ -362,21 +469,51 @@ function PreviewPage() {
               目录索引
             </Button>
             <Drawer
-              title={projectInfo?.name || '项目预览'}
+              title={
+                <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
+                  <img src="/favicon.svg" alt="logo" style={{ width: 24, height: 24 }} />
+                  <span>{projectInfo?.name || '项目预览'}</span>
+                </div>
+              }
               placement="left"
               onClose={() => setMobileDrawerVisible(false)}
               open={mobileDrawerVisible}
               width="80%"
             >
-              <Menu
-                mode="inline"
-                selectedKeys={[selectedFile]}
-                openKeys={openKeys}
-                onOpenChange={setOpenKeys}
-                items={menuItems}
-                onClick={handleMenuClick}
-                className="preview-menu"
-              />
+              <div className="preview-sider-header" style={{ padding: '0 0 16px' }}>
+                {projectInfo?.description && (
+                  <p className="preview-project-desc">{projectInfo.description}</p>
+                )}
+              </div>
+              
+              {/* 搜索框 */}
+              <div style={{ padding: '0 0 12px' }}>
+                <Input.Search
+                  placeholder="搜索文档内容..."
+                  allowClear
+                  value={searchKeyword}
+                  onChange={(e) => setSearchKeyword(e.target.value)}
+                  onSearch={handleSearch}
+                  loading={isSearching}
+                  enterButton
+                />
+              </div>
+              
+              {filteredTreeData.length > 0 ? (
+                <Menu
+                  mode="inline"
+                  selectedKeys={[selectedFile]}
+                  openKeys={openKeys}
+                  onOpenChange={setOpenKeys}
+                  items={menuItems}
+                  onClick={handleMenuClick}
+                  className="preview-menu"
+                />
+              ) : (
+                <div style={{ padding: '20px', textAlign: 'center', color: '#999' }}>
+                  <Empty image={Empty.PRESENTED_IMAGE_SIMPLE} description="未找到匹配文档" />
+                </div>
+              )}
             </Drawer>
           </>
         ) : (
@@ -387,11 +524,47 @@ function PreviewPage() {
             collapsed={siderCollapsed}
             collapsedWidth={0}
           >
-            <SiderContent />
+            <div className="preview-sider-header">
+              <div style={{ display: 'flex', alignItems: 'center', gap: 8, marginBottom: 8 }}>
+                <img src="/favicon.svg" alt="logo" style={{ width: 24, height: 24 }} />
+                <h2 style={{ margin: 0 }}>{projectInfo?.name || '项目预览'}</h2>
+              </div>
+              {projectInfo?.description && (
+                <p className="preview-project-desc">{projectInfo.description}</p>
+              )}
+            </div>
+            
+            {/* 搜索框 */}
+            <div style={{ padding: '12px 16px 4px' }}>
+              <Input.Search
+                placeholder="搜索文档内容..."
+                allowClear
+                value={searchKeyword}
+                onChange={(e) => setSearchKeyword(e.target.value)}
+                onSearch={handleSearch}
+                loading={isSearching}
+                enterButton
+              />
+            </div>
+            
+            {filteredTreeData.length > 0 ? (
+              <Menu
+                mode="inline"
+                selectedKeys={[selectedFile]}
+                openKeys={openKeys}
+                onOpenChange={setOpenKeys}
+                items={menuItems}
+                onClick={handleMenuClick}
+                className="preview-menu"
+              />
+            ) : (
+              <div style={{ padding: '20px', textAlign: 'center', color: '#999' }}>
+                <Empty image={Empty.PRESENTED_IMAGE_SIMPLE} description="未找到匹配文档" />
+              </div>
+            )}
           </Sider>
         )}
 
-        {/* 右侧内容区 */}
         <Layout className="preview-content-layout">
           <Content className="preview-content" ref={contentRef}>
             <div className={`preview-content-wrapper ${viewMode === 'pdf' ? 'pdf-mode' : ''}`}>
@@ -407,7 +580,7 @@ function PreviewPage() {
                   filename={pdfFilename}
                 />
               ) : (
-                <div className="markdown-body" onClick={handleContentClick}>
+                <div className="markdown-body" onClick={handleContentClick} ref={viewerRef}>
                   <Viewer
                     value={markdownContent}
                     plugins={plugins}
@@ -416,7 +589,6 @@ function PreviewPage() {
               )}
             </div>
 
-            {/* 返回顶部按钮 - 仅在markdown模式显示 */}
             {viewMode === 'markdown' && (
               <FloatButton
                 icon={<VerticalAlignTopOutlined />}
@@ -431,7 +603,6 @@ function PreviewPage() {
             )}
           </Content>
 
-          {/* 右侧TOC面板（仅桌面端且markdown模式显示） */}
           {!isMobile && viewMode === 'markdown' && !tocCollapsed && (
             <Sider width={250} theme="light" className="preview-toc-sider">
               <div className="toc-header">
@@ -455,7 +626,7 @@ function PreviewPage() {
                       title: (
                         <div style={{ paddingLeft: `${(item.level - 1) * 12}px`, display: 'flex', alignItems: 'center', gap: '4px' }}>
                           <FileTextOutlined style={{ fontSize: '12px', color: '#8c8c8c' }} />
-                          {item.title}
+                          <HighlightText text={item.title} keyword={searchKeyword} />
                         </div>
                       ),
                     }))}
@@ -468,7 +639,6 @@ function PreviewPage() {
           )}
         </Layout>
 
-        {/* TOC展开按钮（仅桌面端） */}
         {!isMobile && tocCollapsed && (
           <Button
             type="primary"
@@ -481,7 +651,6 @@ function PreviewPage() {
         )}
       </Layout>
 
-      {/* 密码验证模态框 */}
       <Modal
         title={
           <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
diff --git a/frontend/src/pages/ProjectList/ProjectList.jsx b/frontend/src/pages/ProjectList/ProjectList.jsx
index d76e590..8d397f0 100644
--- a/frontend/src/pages/ProjectList/ProjectList.jsx
+++ b/frontend/src/pages/ProjectList/ProjectList.jsx
@@ -418,7 +418,7 @@ function ProjectList({ type = 'my' }) {
       navigate(`/projects/${item.project_id}/docs`)
     } else if (item.type === 'file') {
       // 跳转到文件
-      navigate(`/projects/${item.project_id}/docs?file=${encodeURIComponent(item.file_path)}`)
+      navigate(`/projects/${item.project_id}/docs?file=${encodeURIComponent(item.file_path)}&keyword=${encodeURIComponent(searchKeyword)}`)
     }
   }
 
@@ -530,7 +530,7 @@ function ProjectList({ type = 'my' }) {
                 <h3>{project.name}</h3>
                 <p className="project-description">{project.description || '暂无描述'}</p>
                 <div className="project-meta">
-                  <span>访问: {project.visit_count}</span>
+                  <span>文档数: {project.doc_count || 0}</span>
                   {type === 'share' && project.owner_name && (
                     <span style={{ marginLeft: 12 }}>
                       所有者: {project.owner_nickname || project.owner_name}
diff --git a/frontend/vite.config.js b/frontend/vite.config.js
index c07dcac..ddb959e 100644
--- a/frontend/vite.config.js
+++ b/frontend/vite.config.js
@@ -19,6 +19,7 @@ export default defineConfig({
     },
   },
   server: {
+    host: '0.0.0.0',
     port: 5173,
     open: true,
     proxy: {
diff --git a/frontend/yarn.lock b/frontend/yarn.lock
index b8ad9fb..6c3f23f 100644
--- a/frontend/yarn.lock
+++ b/frontend/yarn.lock
@@ -3209,6 +3209,11 @@ hastscript@^9.0.0:
     property-information "^7.0.0"
     space-separated-tokens "^2.0.0"
 
+highlight-words-core@^1.2.0:
+  version "1.2.3"
+  resolved "https://registry.npmmirror.com/highlight-words-core/-/highlight-words-core-1.2.3.tgz#781f37b2a220bf998114e4ef8c8cb6c7a4802ea8"
+  integrity sha512-m1O9HW3/GNHxzSIXWw1wCNXXsgLlxrP0OI6+ycGUhiUHkikqW3OrwVHz+lxeNBe5yqLESdIcj8PowHQ2zLvUvQ==
+
 highlight.js@^11.7.0, highlight.js@~11.11.0:
   version "11.11.1"
   resolved "https://registry.npmmirror.com/highlight.js/-/highlight.js-11.11.1.tgz"
@@ -3680,6 +3685,11 @@ make-event-props@^2.0.0:
   resolved "https://registry.npmmirror.com/make-event-props/-/make-event-props-2.0.0.tgz#41f7a6e96841296d6835aebe94be86c25602f923"
   integrity sha512-G/hncXrl4Qt7mauJEXSg3AcdYzmpkIITTNl5I+rH9sog5Yw0kK6vseJjCaPfOXqOqQuPUP89Rkhfz5kPS8ijtw==
 
+mark.js@^8.11.1:
+  version "8.11.1"
+  resolved "https://registry.npmmirror.com/mark.js/-/mark.js-8.11.1.tgz#180f1f9ebef8b0e638e4166ad52db879beb2ffc5"
+  integrity sha512-1I+1qpDt4idfgLQG+BNWmrqku+7/2bi5nLf4YwF8y8zXvmfiTBY3PV3ZibfrjBueCByROpuBjLLFCajqkgYoLQ==
+
 markdown-table@^3.0.0:
   version "3.0.4"
   resolved "https://registry.npmmirror.com/markdown-table/-/markdown-table-3.0.4.tgz"
@@ -4025,6 +4035,11 @@ mdast-util-to-string@^4.0.0:
   dependencies:
     "@types/mdast" "^4.0.0"
 
+memoize-one@^4.0.0:
+  version "4.1.0"
+  resolved "https://registry.npmmirror.com/memoize-one/-/memoize-one-4.1.0.tgz#a2387c58c03fff27ca390c31b764a79addf3f906"
+  integrity sha512-2GApq0yI/b22J2j9rhbrAlsHb0Qcz+7yWxeLG8h+95sl1XPUgeLimQSOdur4Vw7cUhrBHwaUZxWFZueojqNRzA==
+
 meow@^13.0.0:
   version "13.2.0"
   resolved "https://registry.npmmirror.com/meow/-/meow-13.2.0.tgz#6b7d63f913f984063b3cc261b6e8800c4cd3474f"
@@ -5318,6 +5333,14 @@ react-easy-crop@^5.5.3:
     normalize-wheel "^1.0.1"
     tslib "^2.0.1"
 
+react-highlight-words@^0.21.0:
+  version "0.21.0"
+  resolved "https://registry.npmmirror.com/react-highlight-words/-/react-highlight-words-0.21.0.tgz#a109acdf7dc6fac3ed7db82e9cba94e8d65c281c"
+  integrity sha512-SdWEeU9fIINArEPO1rO5OxPyuhdEKZQhHzZZP1ie6UeXQf+CjycT1kWaB+9bwGcVbR0NowuHK3RqgqNg6bgBDQ==
+  dependencies:
+    highlight-words-core "^1.2.0"
+    memoize-one "^4.0.0"
+
 react-is@^16.13.1:
   version "16.13.1"
   resolved "https://registry.npmmirror.com/react-is/-/react-is-16.13.1.tgz"