diff --git a/config/llm_config.py b/config/llm_config.py
index a3429d2..c4bc6b4 100644
--- a/config/llm_config.py
+++ b/config/llm_config.py
@@ -20,7 +20,7 @@ class LLMConfig:
     provider: str = os.environ.get("LLM_PROVIDER", "openai")  # openai, gemini, etc.
     api_key: str = os.environ.get("OPENAI_API_KEY", "sk-2187174de21548b0b8b0c92129700199")
     base_url: str = os.environ.get("OPENAI_BASE_URL", "http://127.0.0.1:9999/v1")
-    model: str = os.environ.get("OPENAI_MODEL", "claude-sonnet-4-5")
+    model: str = os.environ.get("OPENAI_MODEL", "gemini-3-flash")
     temperature: float = 0.5
     max_tokens: int = 8192  # 降低默认值,避免某些API不支持过大的值
 
diff --git a/prompts.py b/prompts.py
index be103f9..d09cf7e 100644
--- a/prompts.py
+++ b/prompts.py
@@ -1,7 +1,6 @@
 data_analysis_system_prompt = """你是一个专业的数据分析助手，运行在Jupyter Notebook环境中，能够根据用户需求生成和执行Python数据分析代码。
 
-[TARGET] **核心使命**：
-- 接收自然语言需求，分阶段生成高效、安全的数据分析代码。
+[TARGET] **核心使命**：+、安全的数据分析代码。
 - 深度挖掘数据，不仅仅是绘图，更要发现数据背后的业务洞察。
 - 输出高质量、可落地的业务分析报告。
 
diff --git a/web/main.py b/web/main.py
index 9abac5b..21f6db1 100644
--- a/web/main.py
+++ b/web/main.py
@@ -5,6 +5,7 @@ import threading
 import glob
 import uuid
 import json
+from datetime import datetime
 from typing import Optional, Dict, List
 from fastapi import FastAPI, UploadFile, File, BackgroundTasks, HTTPException, Query
 from fastapi.middleware.cors import CORSMiddleware
@@ -18,8 +19,8 @@ sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 from data_analysis_agent import DataAnalysisAgent
 from config.llm_config import LLMConfig
 from utils.create_session_dir import create_session_output_dir
-from merge_excel import merge_excel_files
-from sort_csv import sort_csv_by_time
+from config.llm_config import LLMConfig
+from utils.create_session_dir import create_session_output_dir
 
 app = FastAPI(title="IOV Data Analysis Agent")
 
@@ -55,6 +56,7 @@ class SessionData:
         self.last_updated: str = ""
         self.user_requirement: str = ""
         self.file_list: List[str] = []
+        self.reusable_script: Optional[str] = None  # 新增：可复用脚本路径
 
 
 class SessionManager:
@@ -70,7 +72,74 @@ class SessionManager:
 
 
     def get_session(self, session_id: str) -> Optional[SessionData]:
-        return self.sessions.get(session_id)
+        if session_id in self.sessions:
+            return self.sessions[session_id]
+            
+        # Fallback: Try to reconstruct from disk for history sessions
+        output_dir = os.path.join("outputs", f"session_{session_id}")
+        if os.path.exists(output_dir) and os.path.isdir(output_dir):
+            return self._reconstruct_session(session_id, output_dir)
+            
+        return None
+
+    def _reconstruct_session(self, session_id: str, output_dir: str) -> SessionData:
+        """从磁盘目录重建会话对象"""
+        session = SessionData(session_id)
+        session.output_dir = output_dir
+        session.is_running = False
+        session.current_round = session.max_rounds
+        session.progress_percentage = 100.0
+        session.status_message = "已完成 (历史记录)"
+        
+        # Recover Log
+        log_path = os.path.join(output_dir, "process.log")
+        if os.path.exists(log_path):
+            session.log_file = log_path
+            
+        # Recover Report
+        # 宽容查找：扫描所有 .md 文件，优先取包含 "report" 或 "报告" 的文件
+        md_files = glob.glob(os.path.join(output_dir, "*.md"))
+        if md_files:
+            # 默认取第一个
+            chosen = md_files[0]
+            # 尝试找更好的匹配
+            for md in md_files:
+                fname = os.path.basename(md).lower()
+                if "report" in fname or "报告" in fname:
+                    chosen = md
+                    break
+            session.generated_report = chosen
+            
+        # Recover Script (查找可能的脚本文件)
+        possible_scripts = ["data_analysis_script.py", "script.py", "analysis_script.py"]
+        for s in possible_scripts:
+            p = os.path.join(output_dir, s)
+            if os.path.exists(p):
+                session.reusable_script = p
+                break
+        
+        # Recover Results (images etc)
+        results_json = os.path.join(output_dir, "results.json")
+        if os.path.exists(results_json):
+            try:
+                with open(results_json, "r") as f:
+                     session.analysis_results = json.load(f)
+            except:
+                pass
+        
+        # Recover Metadata
+        try:
+             stat = os.stat(output_dir)
+             dt = datetime.fromtimestamp(stat.st_ctime)
+             session.created_at = dt.strftime("%Y-%m-%d %H:%M:%S")
+        except:
+             pass
+
+        # Cache it
+        with self.lock:
+             self.sessions[session_id] = session
+             
+        return session
 
     def list_sessions(self):
         return list(self.sessions.keys())
@@ -99,7 +168,10 @@ class SessionManager:
                 "max_rounds": session.max_rounds,
                 "created_at": session.created_at,
                 "last_updated": session.last_updated,
-                "user_requirement": session.user_requirement[:100] + "..." if len(session.user_requirement) > 100 else session.user_requirement
+                "created_at": session.created_at,
+                "last_updated": session.last_updated,
+                "user_requirement": session.user_requirement[:100] + "..." if len(session.user_requirement) > 100 else session.user_requirement,
+                "script_path": session.reusable_script  # 新增：返回脚本路径
             }
         return None
 
@@ -227,6 +299,7 @@ def run_analysis_task(session_id: str, files: list, user_requirement: str, is_fo
             
             session.generated_report = result.get("report_file_path", None)
             session.analysis_results = result.get("analysis_results", [])
+            session.reusable_script = result.get("reusable_script_path", None)  # 新增：保存脚本路径
             
             # Save results to json for persistence
             with open(os.path.join(session_output_dir, "results.json"), "w") as f:
@@ -311,7 +384,8 @@ async def get_status(session_id: str = Query(..., description="Session ID")):
         "is_running": session.is_running,
         "log": log_content,
         "has_report": session.generated_report is not None,
-        "report_path": session.generated_report
+        "report_path": session.generated_report,
+        "script_path": session.reusable_script  # 新增：返回脚本路径
     }
 
 @app.get("/api/export")
@@ -453,71 +527,24 @@ async def export_report(session_id: str = Query(..., description="Session ID")):
         media_type='application/zip'
     )
 
+@app.get("/api/download_script")
+async def download_script(session_id: str = Query(..., description="Session ID")):
+    """下载生成的Python脚本"""
+    session = session_manager.get_session(session_id)
+    if not session or not session.reusable_script:
+        raise HTTPException(status_code=404, detail="Script not found")
+        
+    if not os.path.exists(session.reusable_script):
+        raise HTTPException(status_code=404, detail="Script file missing on server")
+        
+    return FileResponse(
+        path=session.reusable_script,
+        filename=os.path.basename(session.reusable_script),
+        media_type='text/x-python'
+    )
+
 # --- Tools API ---
 
-class ToolRequest(BaseModel):
-    source_dir: Optional[str] = "uploads"
-    output_filename: Optional[str] = "merged_output.csv"
-    target_file: Optional[str] = None
-
-@app.post("/api/tools/merge")
-async def tool_merge_excel(req: ToolRequest):
-    """
-    Trigger Excel Merge Tool
-    """
-    try:
-        source = req.source_dir
-        output = req.output_filename
-        
-        import asyncio
-        loop = asyncio.get_event_loop()
-        
-        await loop.run_in_executor(None, lambda: merge_excel_files(source, output))
-        
-        output_abs = os.path.abspath(output)
-        if os.path.exists(output_abs):
-            return {"status": "success", "message": "Merge completed", "output_file": output_abs}
-            
-    except Exception as e:
-        raise HTTPException(status_code=500, detail=str(e))
-
-@app.post("/api/tools/sort")
-async def tool_sort_csv(req: ToolRequest):
-    """
-    Trigger CSV Sort Tool
-    """
-    try:
-        target = req.target_file
-        if not target:
-             raise HTTPException(status_code=400, detail="Target file required")
-             
-        import asyncio
-        loop = asyncio.get_event_loop()
-        
-        await loop.run_in_executor(None, lambda: sort_csv_by_time(target))
-        
-        return {"status": "success", "message": f"Sorted {target} by time"}
-    except Exception as e:
-         raise HTTPException(status_code=500, detail=str(e))
-
-# --- Help API ---
-
-@app.get("/api/help/troubleshooting")
-async def get_troubleshooting_guide():
-    """
-    Returns the content of troubleshooting_guide.md
-    """
-    guide_path = os.path.expanduser("~/.gemini/antigravity/brain/3ff617fe-5f27-4ab8-b61b-c634f2e75255/troubleshooting_guide.md")
-    
-    if not os.path.exists(guide_path):
-        return {"content": "# Troubleshooting Guide Not Found\n\nCould not locate the guide artifact."}
-        
-    try:
-        with open(guide_path, "r", encoding="utf-8") as f:
-            content = f.read()
-        return {"content": content}
-    except Exception as e:
-        return {"content": f"# Error Loading Guide\n\n{e}"}
 
 
 # --- 新增API端点 ---
@@ -553,6 +580,61 @@ async def delete_specific_session(session_id: str):
         raise HTTPException(status_code=404, detail="Session not found")
     return {"status": "deleted", "session_id": session_id}
 
+    return {"status": "deleted", "session_id": session_id}
+
+
+# --- History API ---
+
+@app.get("/api/history")
+async def get_history():
+    """
+    Get list of past analysis sessions from outputs directory
+    """
+    history = []
+    output_base = "outputs"
+    
+    if not os.path.exists(output_base):
+        return {"history": []}
+        
+    try:
+        # Scan for session_* directories
+        for entry in os.scandir(output_base):
+            if entry.is_dir() and entry.name.startswith("session_"):
+                # Extract timestamp from folder name: session_20250101_120000
+                session_id = entry.name.replace("session_", "")
+                
+                # Check creation time or extract from name
+                try:
+                    # Try to parse timestamp from ID if it matches format
+                    # Format: YYYYMMDD_HHMMSS
+                    timestamp_str = session_id
+                    dt = datetime.strptime(timestamp_str, "%Y%m%d_%H%M%S")
+                    display_time = dt.strftime("%Y-%m-%d %H:%M:%S")
+                    sort_key = dt.timestamp()
+                except ValueError:
+                    # Fallback to file creation time
+                    sort_key = entry.stat().st_ctime
+                    display_time = datetime.fromtimestamp(sort_key).strftime("%Y-%m-%d %H:%M:%S")
+
+                history.append({
+                    "id": session_id,
+                    "timestamp": display_time,
+                    "sort_key": sort_key,
+                    "name": f"Session {display_time}"
+                })
+        
+        # Sort by latest first
+        history.sort(key=lambda x: x["sort_key"], reverse=True)
+        
+        # Cleanup internal sort key
+        for item in history:
+            del item["sort_key"]
+            
+        return {"history": history}
+        
+    except Exception as e:
+        print(f"Error scanning history: {e}")
+        return {"history": []}
 
 if __name__ == "__main__":
     import uvicorn
diff --git a/web/static/clean_style.css b/web/static/clean_style.css
new file mode 100644
index 0000000..a31b0bd
--- /dev/null
+++ b/web/static/clean_style.css
@@ -0,0 +1,535 @@
+/* Clean Style - IOV Data Analysis Agent */
+
+:root {
+    --primary-color: #2563EB;
+    /* Tech Blue */
+    --primary-hover: #1D4ED8;
+    --bg-color: #FFFFFF;
+    --sidebar-bg: #F9FAFB;
+    --text-primary: #111827;
+    --text-secondary: #6B7280;
+    --border-color: #E5E7EB;
+    --card-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
+    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
+}
+
+* {
+    box-sizing: border-box;
+    margin: 0;
+    padding: 0;
+}
+
+body {
+    font-family: var(--font-family);
+    color: var(--text-primary);
+    background-color: var(--bg-color);
+    line-height: 1.5;
+    height: 100vh;
+    overflow: hidden;
+}
+
+.app-container {
+    display: flex;
+    height: 100vh;
+}
+
+/* Sidebar */
+.sidebar {
+    width: 240px;
+    /* Compact width */
+    background-color: var(--sidebar-bg);
+    border-right: 1px solid var(--border-color);
+    display: flex;
+    flex-direction: column;
+    padding: 1rem;
+    flex-shrink: 0;
+}
+
+.brand {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    margin-bottom: 1.5rem;
+    font-weight: 600;
+    color: var(--text-primary);
+}
+
+.brand i {
+    color: var(--primary-color);
+    font-size: 1.5rem;
+}
+
+.nav-menu {
+    display: flex;
+    flex-direction: column;
+    gap: 0.5rem;
+    flex: 1;
+    overflow-y: hidden;
+    /* Let history list handle scroll */
+}
+
+.nav-item {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    padding: 0.75rem 1rem;
+    border-radius: 0.375rem;
+    color: var(--text-secondary);
+    text-decoration: none;
+    cursor: pointer;
+    transition: all 0.2s;
+    font-size: 0.95rem;
+    border: none;
+    background: none;
+    width: 100%;
+    text-align: left;
+}
+
+.nav-item:hover {
+    background-color: #F3F4F6;
+    color: var(--text-primary);
+}
+
+.nav-item.active {
+    background-color: #EFF6FF;
+    color: var(--primary-color);
+    font-weight: 500;
+}
+
+.nav-item i {
+    width: 1.25rem;
+    text-align: center;
+}
+
+.nav-divider {
+    height: 1px;
+    background-color: var(--border-color);
+    margin: 1rem 0 0.5rem 0;
+}
+
+.nav-section-title {
+    font-size: 0.75rem;
+    text-transform: uppercase;
+    color: var(--text-secondary);
+    font-weight: 600;
+    letter-spacing: 0.05em;
+    margin-bottom: 0.5rem;
+    padding-left: 0.5rem;
+}
+
+/* History List */
+.history-list {
+    flex: 1;
+    overflow-y: auto;
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+    padding-right: 5px;
+}
+
+.history-item {
+    font-size: 0.85rem;
+    color: var(--text-secondary);
+    padding: 0.5rem 0.75rem;
+    border-radius: 0.375rem;
+    cursor: pointer;
+    transition: all 0.2s;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+}
+
+.history-item:hover {
+    background-color: #F3F4F6;
+    color: var(--text-primary);
+}
+
+.history-item.active {
+    background-color: #EFF6FF;
+    color: var(--primary-color);
+}
+
+
+.status-bar {
+    margin-top: auto;
+    padding-top: 1rem;
+    border-top: 1px solid var(--border-color);
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    font-size: 0.875rem;
+    color: var(--text-secondary);
+}
+
+.status-dot {
+    width: 8px;
+    height: 8px;
+    border-radius: 50%;
+    background-color: #D1D5DB;
+}
+
+.status-dot.running {
+    background-color: var(--primary-color);
+    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
+}
+
+/* Main Content */
+.main-content {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    height: 100vh;
+    overflow: hidden;
+    background-color: #FFFFFF;
+}
+
+.header {
+    height: 64px;
+    border-bottom: 1px solid var(--border-color);
+    display: flex;
+    align-items: center;
+    padding: 0 2rem;
+    background-color: #FFFFFF;
+}
+
+.header h2 {
+    font-size: 1.25rem;
+    font-weight: 600;
+}
+
+.content-area {
+    flex: 1;
+    overflow-y: auto;
+    padding: 2rem;
+    background-color: #ffffff;
+}
+
+/* Sections & Panel */
+.section {
+    display: none;
+    max-width: 1000px;
+    margin: 0 auto;
+}
+
+.section.active {
+    display: block;
+}
+
+.analysis-grid {
+    display: grid;
+    grid-template-columns: 350px 1fr;
+    gap: 2rem;
+    height: calc(100vh - 64px - 4rem);
+}
+
+.panel {
+    background: #FFFFFF;
+    border: 1px solid var(--border-color);
+    border-radius: 0.5rem;
+    padding: 1.5rem;
+    display: flex;
+    flex-direction: column;
+    gap: 1.5rem;
+}
+
+.panel-title {
+    font-size: 1rem;
+    font-weight: 600;
+    color: var(--text-primary);
+    margin-bottom: 0.5rem;
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+}
+
+/* Forms */
+.form-group {
+    display: flex;
+    flex-direction: column;
+    gap: 0.5rem;
+}
+
+.form-label {
+    font-size: 0.875rem;
+    font-weight: 500;
+    color: var(--text-secondary);
+}
+
+.form-input,
+.form-textarea {
+    padding: 0.625rem 0.875rem;
+    border: 1px solid var(--border-color);
+    border-radius: 0.375rem;
+    font-family: inherit;
+    font-size: 0.9rem;
+    color: var(--text-primary);
+    outline: none;
+    transition: border-color 0.2s;
+    width: 100%;
+}
+
+.form-input:focus,
+.form-textarea:focus {
+    border-color: var(--primary-color);
+    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.1);
+}
+
+.form-textarea {
+    resize: vertical;
+    min-height: 100px;
+}
+
+/* Buttons */
+.btn {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    gap: 0.5rem;
+    padding: 0.625rem 1.25rem;
+    border-radius: 0.375rem;
+    font-weight: 500;
+    font-size: 0.9rem;
+    cursor: pointer;
+    transition: all 0.2s;
+    border: 1px solid transparent;
+}
+
+.btn-primary {
+    background-color: var(--primary-color);
+    color: white;
+}
+
+.btn-primary:hover {
+    background-color: var(--primary-hover);
+}
+
+.btn-secondary {
+    background-color: white;
+    border-color: var(--border-color);
+    color: var(--text-primary);
+}
+
+.btn-secondary:hover {
+    background-color: #F9FAFB;
+    border-color: #D1D5DB;
+}
+
+.btn-sm {
+    padding: 0.375rem 0.75rem;
+    font-size: 0.875rem;
+}
+
+/* Upload Area */
+.upload-area {
+    border: 2px dashed var(--border-color);
+    border-radius: 0.5rem;
+    padding: 2rem;
+    text-align: center;
+    cursor: pointer;
+    transition: all 0.2s;
+    background-color: #F9FAFB;
+}
+
+.upload-area:hover,
+.upload-area.dragover {
+    border-color: var(--primary-color);
+    background-color: #EFF6FF;
+}
+
+.upload-icon {
+    font-size: 1.5rem;
+    color: var(--text-secondary);
+    margin-bottom: 0.75rem;
+}
+
+.file-list {
+    margin-top: 1rem;
+    display: flex;
+    flex-direction: column;
+    gap: 0.5rem;
+}
+
+.file-item {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    font-size: 0.85rem;
+    color: var(--text-primary);
+    background: #FFFFFF;
+    padding: 0.5rem;
+    border: 1px solid var(--border-color);
+    border-radius: 0.25rem;
+}
+
+/* Tabs */
+.tabs {
+    display: flex;
+    gap: 1rem;
+    margin-left: 1rem;
+}
+
+.tab {
+    padding: 0.25rem 0.5rem;
+    font-size: 0.9rem;
+    color: var(--text-secondary);
+    cursor: pointer;
+    border-bottom: 2px solid transparent;
+    transition: all 0.2s;
+}
+
+.tab:hover {
+    color: var(--text-primary);
+}
+
+.tab.active {
+    color: var(--primary-color);
+    border-bottom-color: var(--primary-color);
+    font-weight: 500;
+}
+
+/* Log & Report Content */
+.output-container {
+    flex: 1;
+    overflow-y: hidden;
+    /* Individual tabs scroll */
+    background: #F9FAFB;
+    border: 1px solid var(--border-color);
+    border-radius: 0.375rem;
+    padding: 1rem;
+    position: relative;
+    display: flex;
+    flex-direction: column;
+}
+
+#logsTab {
+    background-color: #1a1b26;
+    color: #a9b1d6;
+    font-family: 'JetBrains Mono', 'Menlo', 'Monaco', 'Courier New', monospace;
+    padding: 1.5rem;
+}
+
+.log-content {
+    font-family: inherit;
+    font-size: 0.85rem;
+    white-space: pre-wrap;
+    line-height: 1.6;
+    margin: 0;
+}
+
+.report-content {
+    font-size: 0.95rem;
+    line-height: 1.7;
+    color: #1F2937;
+}
+
+.report-content img {
+    max-width: 100%;
+    border-radius: 0.375rem;
+    margin: 1rem 0;
+    box-shadow: var(--card-shadow);
+}
+
+/* Empty State */
+.empty-state {
+    text-align: center;
+    padding: 4rem 2rem;
+    color: var(--text-secondary);
+}
+
+/* Utilities */
+.hidden {
+    display: none !important;
+}
+
+/* Gallery Carousel */
+.carousel-container {
+    position: relative;
+    width: 100%;
+    flex: 1;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    background: #F3F4F6;
+    border-radius: 0.5rem;
+    overflow: hidden;
+    margin-bottom: 1rem;
+}
+
+.carousel-slide {
+    width: 100%;
+    height: 100%;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    padding: 2rem;
+}
+
+.carousel-slide img {
+    max-width: 100%;
+    max-height: 500px;
+    object-fit: contain;
+    border-radius: 0.25rem;
+    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
+    transition: transform 0.2s;
+    background: white;
+}
+
+.carousel-btn {
+    position: absolute;
+    top: 50%;
+    transform: translateY(-50%);
+    background: rgba(255, 255, 255, 0.9);
+    border: 1px solid var(--border-color);
+    border-radius: 50%;
+    width: 44px;
+    height: 44px;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    cursor: pointer;
+    z-index: 10;
+    color: var(--text-primary);
+    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
+    transition: all 0.2s;
+}
+
+.carousel-btn:hover {
+    background: var(--primary-color);
+    color: white;
+    border-color: var(--primary-color);
+    transform: translateY(-50%) scale(1.1);
+}
+
+.carousel-btn.prev {
+    left: 1rem;
+}
+
+.carousel-btn.next {
+    right: 1rem;
+}
+
+.image-info {
+    width: 100%;
+    text-align: center;
+    color: var(--text-primary);
+    background: white;
+    padding: 1rem;
+    border-radius: 0.5rem;
+    border: 1px solid var(--border-color);
+}
+
+.image-title {
+    font-weight: 600;
+    font-size: 1.1rem;
+    margin-bottom: 0.5rem;
+    color: var(--primary-color);
+}
+
+.image-desc {
+    font-size: 0.9rem;
+    color: var(--text-secondary);
+}
\ No newline at end of file
diff --git a/web/static/index.html b/web/static/index.html
index fcfbd6f..c24e979 100644
--- a/web/static/index.html
+++ b/web/static/index.html
@@ -5,18 +5,20 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>IOV Data Analysis Agent</title>
-    <link rel="stylesheet" href="/static/style.css?v=2.0">
+    <link rel="stylesheet" href="/static/clean_style.css">
 
-    <!-- Google Fonts -->
+    <!-- Fonts -->
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
     <link
-        href="https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&family=Inter:wght@300;400;500;600&display=swap"
+        href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@400;500&display=swap"
         rel="stylesheet">
-    <!-- Markdown Parser -->
-    <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
-    <!-- Font Awesome -->
+
+    <!-- Icons -->
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.4.0/css/all.min.css">
+
+    <!-- Markdown -->
+    <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
 </head>
 
 <body>
@@ -24,162 +26,140 @@
         <!-- Sidebar -->
         <aside class="sidebar">
             <div class="brand">
-                <i class="fa-solid fa-robot"></i>
-                <h1>IOV Agent</h1>
+                <i class="fa-solid fa-cube"></i>
+                <span>IOV Agent</span>
             </div>
 
-            <!-- Navigation -->
-            <nav class="main-nav">
-                <button class="nav-btn active" onclick="switchView('analysis')">
+            <nav class="nav-menu">
+                <button class="nav-item active" onclick="switchView('analysis')">
                     <i class="fa-solid fa-chart-line"></i> Analysis
                 </button>
-                <button class="nav-btn" onclick="switchView('tools')">
-                    <i class="fa-solid fa-toolbox"></i> Data Tools
-                </button>
-                <button class="nav-btn" onclick="switchView('gallery')">
-                    <i class="fa-solid fa-images"></i> Gallery
-                </button>
-                <button class="nav-btn" onclick="switchView('help')">
-                    <i class="fa-solid fa-circle-question"></i> Help
-                </button>
+
+                <div class="nav-divider"></div>
+                <div class="nav-section-title">History</div>
+                <div id="historyList" class="history-list">
+                    <!-- History items loaded via JS -->
+                    <div style="padding:0.5rem; font-size:0.8rem; color:#9CA3AF;">Loading...</div>
+                </div>
             </nav>
 
-            <!-- Analysis Controls (Visible only in Analysis View) -->
-            <div id="analysisControls" class="control-group-wrapper">
-                <div class="control-group">
-                    <h3>1. Data Upload</h3>
-                    <div class="upload-zone" id="uploadZone">
-                        <i class="fa-solid fa-cloud-arrow-up"></i>
-                        <p>Drag & Drop CSV/Excel</p>
-                        <input type="file" id="fileInput" accept=".csv,.xlsx,.xls" multiple hidden>
-                        <button class="btn secondary" onclick="document.getElementById('fileInput').click()">Select
-                            Files</button>
-                        <div id="fileList" class="file-list"></div>
-                    </div>
-                </div>
-
-                <div class="control-group">
-                    <h3>2. Analysis Config</h3>
-                    <textarea id="requirementInput"
-                        placeholder="Enter your analysis requirement here...">基于所有运维工单，整理一份工单健康度报告...</textarea>
-                    <button id="startBtn" class="btn primary">
-                        <i class="fa-solid fa-play"></i> Start Analysis
-                    </button>
-                </div>
-            </div>
-
-            <div class="status-indicator">
-                <span id="statusDot" class="dot"></span>
-                <span id="statusText">Idle</span>
+            <div class="status-bar">
+                <div id="statusDot" class="status-dot"></div>
+                <span id="statusText">Ready</span>
             </div>
         </aside>
 
-        <!-- Main Content Area -->
+        <!-- Main Content -->
         <main class="main-content">
+            <header class="header">
+                <h2 id="pageTitle">Analysis Dashboard</h2>
+            </header>
 
-            <!-- VIEW: ANALYSIS -->
-            <div id="viewAnalysis" class="view-section active">
-                <div class="tabs">
-                    <button class="tab-btn active" onclick="switchTab('logs')">
-                        <i class="fa-solid fa-terminal"></i> Live Logs
-                    </button>
-                    <button class="tab-btn" onclick="switchTab('report')">
-                        <i class="fa-solid fa-file-invoice-dollar"></i> Report
-                    </button>
-                    <div style="margin-left: auto; display: flex; align-items: center;">
-                        <button id="exportBtn" class="btn secondary"
-                            style="padding: 0.4rem 1rem; font-size: 0.8rem; width: auto;" onclick="triggerExport()">
-                            <i class="fa-solid fa-download"></i> Export Report (ZIP)
-                        </button>
-                    </div>
-                </div>
+            <div class="content-area">
+                <!-- VIEW: ANALYSIS -->
+                <div id="viewAnalysis" class="section active">
+                    <div class="analysis-grid">
 
-                <!-- Log View -->
-                <div id="logsTab" class="tab-content active">
-                    <div class="terminal-window">
-                        <pre id="logOutput">Waiting to start...</pre>
-                    </div>
-                </div>
+                        <!-- Configuration Panel -->
+                        <div class="panel">
+                            <div class="panel-title">
+                                <span>Configuration</span>
+                            </div>
 
-                <!-- Report View -->
-                <div id="reportTab" class="tab-content">
-                    <div id="reportContainer" class="markdown-body">
-                        <div class="empty-state">
-                            <i class="fa-solid fa-chart-simple"></i>
-                            <p>No report generated yet.</p>
+                            <div class="form-group">
+                                <label class="form-label">1. Data Upload</label>
+                                <div id="uploadZone" class="upload-area">
+                                    <i class="fa-solid fa-cloud-arrow-up upload-icon"></i>
+                                    <p>Click or Drag CSV/Excel Files</p>
+                                    <div id="fileList" class="file-list"></div>
+                                </div>
+                                <input type="file" id="fileInput" multiple accept=".csv,.xlsx,.xls" hidden>
+                            </div>
+
+                            <div class="form-group">
+                                <label class="form-label">2. Requirement</label>
+                                <textarea id="requirementInput" class="form-textarea"
+                                    placeholder="Describe what you want to analyze..."></textarea>
+                            </div>
+
+                            <button id="startBtn" class="btn btn-primary" style="margin-top: 1rem; width: 100%;">
+                                <i class="fa-solid fa-play"></i> Start Analysis
+                            </button>
                         </div>
+
+                        <!-- Output Panel -->
+                        <div class="panel" style="overflow:hidden; display:flex; flex-direction:column;">
+                            <div class="panel-title" style="margin-bottom:0.5rem;">
+                                <span>Output</span>
+                                <div class="tabs">
+                                    <div class="tab active" onclick="switchTab('logs')">Live Log</div>
+                                    <div class="tab" onclick="switchTab('report')">Report</div>
+                                    <div class="tab" onclick="switchTab('gallery')">Gallery</div>
+                                </div>
+                                <button id="downloadScriptBtn" class="btn btn-sm btn-secondary hidden"
+                                    onclick="downloadScript()" style="margin-left:auto;">
+                                    <i class="fa-solid fa-code"></i> Script
+                                </button>
+                            </div>
+
+                            <div class="output-container" id="outputContainer">
+                                <!-- Logs Tab -->
+                                <div id="logsTab" class="tab-content active" style="height:100%; overflow-y:auto;">
+                                    <pre id="logOutput" class="log-content">Waiting to start...</pre>
+                                </div>
+
+                                <!-- Report Tab -->
+                                <div id="reportTab" class="tab-content hidden" style="height:100%; overflow-y:auto;">
+                                    <div id="reportContainer" class="report-content markdown-body">
+                                        <div class="empty-state">
+                                            <p>Report will appear here after analysis.</p>
+                                        </div>
+                                    </div>
+                                    <div id="followUpSection" class="hidden"
+                                        style="margin-top:2rem; border-top:1px solid var(--border-color); padding-top:1rem;">
+                                        <div class="form-group">
+                                            <label class="form-label">Follow-up Analysis</label>
+                                            <div style="display:flex; gap:0.5rem;">
+                                                <input type="text" id="followUpInput" class="form-input"
+                                                    placeholder="Ask a follow-up question...">
+                                                <button class="btn btn-primary btn-sm"
+                                                    onclick="sendFollowUp()">Send</button>
+                                            </div>
+                                        </div>
+                                    </div>
+                                    <div style="margin-top:1rem; text-align:right">
+                                        <button id="exportBtn" class="btn btn-secondary btn-sm"
+                                            onclick="triggerExport()">
+                                            <i class="fa-solid fa-download"></i> Export ZIP
+                                        </button>
+                                    </div>
+                                </div>
+
+                                <!-- Gallery Tab -->
+                                <div id="galleryTab" class="tab-content hidden"
+                                    style="height:100%; display:flex; flex-direction:column; align-items:center; justify-content:center;">
+                                    <div class="carousel-container">
+                                        <button class="carousel-btn prev" onclick="prevImage()"><i
+                                                class="fa-solid fa-chevron-left"></i></button>
+                                        <div class="carousel-slide" id="carouselSlide">
+                                            <p class="placeholder-text" style="color:var(--text-secondary);">No images
+                                                generated.</p>
+                                        </div>
+                                        <button class="carousel-btn next" onclick="nextImage()"><i
+                                                class="fa-solid fa-chevron-right"></i></button>
+                                    </div>
+                                    <div class="image-info" id="imageInfo" style="margin-top:1rem; text-align:center;">
+                                        <!-- Title/Desc -->
+                                    </div>
+                                </div>
+                            </div>
+                        </div>
+
                     </div>
                 </div>
+
             </div>
-
-            <!-- Follow-up Chat Section -->
-            <div id="followUpSection" class="chat-input-container" style="display: none;">
-                <div class="input-wrapper">
-                    <textarea id="followUpInput"
-                        placeholder="Follow-up question... (e.g. 'Analyze the error codes')"></textarea>
-                    <button id="sendFollowUpBtn" class="btn primary" onclick="sendFollowUp()">
-                        <i class="fa-solid fa-paper-plane"></i>
-                    </button>
-                </div>
-            </div>
-    </div>
-
-    <!-- VIEW: TOOLS -->
-    <div id="viewTools" class="view-section" style="display: none;">
-        <div class="tools-grid">
-            <!-- Tool Card 1: Merge Excel -->
-            <div class="tool-card">
-                <div class="tool-icon"><i class="fa-solid fa-file-csv"></i></div>
-                <h3>Excel to CSV Merger</h3>
-                <p>Merge multiple .xlsx files from the uploads directory into a single CSV for analysis.</p>
-                <div class="tool-actions">
-                    <input type="text" id="mergeSource" value="uploads" placeholder="Source Directory" class="input-sm">
-                    <button class="btn secondary" onclick="triggerMerge()">
-                        <i class="fa-solid fa-bolt"></i> Merge Now
-                    </button>
-                </div>
-                <div id="mergeResult" class="tool-result"></div>
-            </div>
-
-            <!-- Tool Card 2: Sort CSV -->
-            <div class="tool-card">
-                <div class="tool-icon"><i class="fa-solid fa-arrow-down-a-z"></i></div>
-                <h3>Time Sorter</h3>
-                <p>Sort a CSV file by 'SendTime' or time column to fix ordering issues.</p>
-                <div class="tool-actions">
-                    <input type="text" id="sortTarget" value="cleaned_data.csv" placeholder="Target Filename"
-                        class="input-sm">
-                    <button class="btn secondary" onclick="triggerSort()">
-                        <i class="fa-solid fa-sort"></i> Sort Now
-                    </button>
-                </div>
-                <div id="sortResult" class="tool-result"></div>
-            </div>
-        </div>
-    </div>
-
-    <!-- VIEW: GALLERY -->
-    <div id="viewGallery" class="view-section" style="display: none;">
-        <div id="galleryContainer" class="gallery-grid">
-            <div class="empty-state">
-                <i class="fa-solid fa-images"></i>
-                <p>No images generated yet.<br>Start an analysis to see results here.</p>
-            </div>
-        </div>
-    </div>
-
-    <!-- VIEW: HELP -->
-    <div id="viewHelp" class="view-section" style="display: none;">
-        <div class="help-header">
-            <h2>Troubleshooting Guide</h2>
-            <button class="btn secondary" onclick="fetchHelp()">Refresh</button>
-        </div>
-        <div id="helpContainer" class="markdown-body help-body">
-            <p>Loading guide...</p>
-        </div>
-    </div>
-
-    </main>
+        </main>
     </div>
 
     <script src="/static/script.js"></script>
diff --git a/web/static/script.js b/web/static/script.js
index 0e5977a..b894f02 100644
--- a/web/static/script.js
+++ b/web/static/script.js
@@ -1,4 +1,5 @@
 
+// DOM Elements
 const uploadZone = document.getElementById('uploadZone');
 const fileInput = document.getElementById('fileInput');
 const fileList = document.getElementById('fileList');
@@ -8,7 +9,7 @@ const statusDot = document.getElementById('statusDot');
 const statusText = document.getElementById('statusText');
 const logOutput = document.getElementById('logOutput');
 const reportContainer = document.getElementById('reportContainer');
-const galleryContainer = document.getElementById('galleryContainer');
+const downloadScriptBtn = document.getElementById('downloadScriptBtn');
 
 let isRunning = false;
 let pollingInterval = null;
@@ -26,9 +27,12 @@ if (uploadZone) {
         uploadZone.classList.remove('dragover');
         handleFiles(e.dataTransfer.files);
     });
+    uploadZone.addEventListener('click', () => fileInput.click());
 }
+
 if (fileInput) {
     fileInput.addEventListener('change', (e) => handleFiles(e.target.files));
+    fileInput.addEventListener('click', (e) => e.stopPropagation()); // Prevent bubbling to uploadZone
 }
 
 async function handleFiles(files) {
@@ -40,9 +44,8 @@ async function handleFiles(files) {
     for (const file of files) {
         formData.append('files', file);
         const fileItem = document.createElement('div');
-        fileItem.innerText = `📄 ${file.name}`;
-        fileItem.style.fontSize = '0.8rem';
-        fileItem.style.color = '#fff';
+        fileItem.className = 'file-item';
+        fileItem.innerHTML = `<i class="fa-regular fa-file-excel"></i> ${file.name}`;
         fileList.appendChild(fileItem);
     }
 
@@ -52,8 +55,7 @@ async function handleFiles(files) {
             body: formData
         });
         if (res.ok) {
-            const data = await res.json();
-            console.log('Upload success:', data);
+            console.log('Upload success');
         } else {
             alert('Upload failed');
         }
@@ -63,63 +65,75 @@ async function handleFiles(files) {
     }
 }
 
-// --- Start Analysis ---
+// --- Analysis Logic ---
 if (startBtn) {
-    startBtn.addEventListener('click', async () => {
-        if (isRunning) return;
+    startBtn.addEventListener('click', startAnalysis);
+}
 
-        const requirement = requirementInput.value.trim();
-        if (!requirement) {
-            alert('Please enter analysis requirement');
-            return;
-        }
+async function startAnalysis() {
+    if (isRunning) return;
 
-        setRunningState(true);
+    const requirement = requirementInput.value.trim();
+    if (!requirement) {
+        alert('Please enter analysis requirement');
+        return;
+    }
 
-        try {
-            const res = await fetch('/api/start', {
-                method: 'POST',
-                headers: { 'Content-Type': 'application/json' },
-                body: JSON.stringify({ requirement })
-            });
+    setRunningState(true);
 
-            if (res.ok) {
-                const data = await res.json();
-                currentSessionId = data.session_id; // Store Session ID
-                console.log("Started Session:", currentSessionId);
+    try {
+        const res = await fetch('/api/start', {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ requirement })
+        });
 
-                startPolling();
-                switchTab('logs');
-            } else {
-                const err = await res.json();
-                alert('Failed to start: ' + err.detail);
-                setRunningState(false);
-            }
-        } catch (e) {
-            console.error(e);
-            alert('Error starting analysis');
+        if (res.ok) {
+            const data = await res.json();
+            currentSessionId = data.session_id;
+            console.log("Started Session:", currentSessionId);
+
+            startPolling();
+            switchTab('logs');
+        } else {
+            const err = await res.json();
+            alert('Failed to start: ' + err.detail);
             setRunningState(false);
         }
-    });
+    } catch (e) {
+        console.error(e);
+        alert('Error starting analysis');
+        setRunningState(false);
+    }
 }
 
 function setRunningState(running) {
     isRunning = running;
     startBtn.disabled = running;
-    startBtn.innerHTML = running ? '<i class="fa-solid fa-spinner fa-spin"></i> Running...' : '<i class="fa-solid fa-play"></i> Start Analysis';
 
     if (running) {
-        statusDot.className = 'dot running';
-        statusText.innerText = 'Analysis in Progress';
-        if (document.getElementById('followUpSection')) document.getElementById('followUpSection').style.display = 'none';
+        startBtn.innerHTML = '<i class="fa-solid fa-spinner fa-spin"></i> Analysis in Progress...';
+        statusDot.className = 'status-dot running';
+        statusText.innerText = 'Analyzing';
+        statusText.style.color = 'var(--primary-color)';
+
+        // Hide follow-up and download during run
+        const followUpSection = document.getElementById('followUpSection');
+        if (followUpSection) followUpSection.classList.add('hidden');
+        if (downloadScriptBtn) downloadScriptBtn.classList.add('hidden');
     } else {
-        statusDot.className = 'dot done';
+        startBtn.innerHTML = '<i class="fa-solid fa-play"></i> Start Analysis';
+        statusDot.className = 'status-dot';
         statusText.innerText = 'Completed';
-        if (currentSessionId && document.getElementById('followUpSection')) document.getElementById('followUpSection').style.display = 'flex';
+        statusText.style.color = 'var(--text-secondary)';
+
+        const followUpSection = document.getElementById('followUpSection');
+        if (currentSessionId && followUpSection) {
+            followUpSection.classList.remove('hidden');
+        }
     }
 }
 
-// --- Status Polling ---
 function startPolling() {
     if (pollingInterval) clearInterval(pollingInterval);
     if (!currentSessionId) return;
@@ -131,20 +145,31 @@ function startPolling() {
             const data = await res.json();
 
             // Update Logs
-            logOutput.innerText = data.log || "Waiting for logs...";
-            // Auto scroll to bottom
-            const term = document.querySelector('.terminal-window');
-            if (term) term.scrollTop = term.scrollHeight;
+            logOutput.innerText = data.log || "Waiting for output...";
+
+            // Auto scroll
+            const logTab = document.getElementById('logsTab');
+            if (logTab) logTab.scrollTop = logTab.scrollHeight;
 
             if (!data.is_running && isRunning) {
-                // Just finished
+                // Finished
                 setRunningState(false);
                 clearInterval(pollingInterval);
 
                 if (data.has_report) {
-                    loadReport();
-                    loadGallery(); // Load images when done
+                    await loadReport();
+
+                    // 强制跳转到 Report Tab
                     switchTab('report');
+                    console.log("Analysis done, switched to report tab");
+                }
+
+                // Check for script
+                if (data.script_path) {
+                    if (downloadScriptBtn) {
+                        downloadScriptBtn.classList.remove('hidden');
+                        downloadScriptBtn.style.display = 'inline-flex';
+                    }
                 }
             }
         } catch (e) {
@@ -153,129 +178,122 @@ function startPolling() {
     }, 2000);
 }
 
+// --- Report Logic ---
 async function loadReport() {
     if (!currentSessionId) return;
     try {
         const res = await fetch(`/api/report?session_id=${currentSessionId}`);
         const data = await res.json();
 
-        // Render Markdown
-        reportContainer.innerHTML = marked.parse(data.content);
-
-        // Fix images relative path for display if needed
-        // The backend should return a base_path or we handle it here
-        if (data.base_path) {
-            // Backend already handled replacement? 
-            // The backend returns content with updated paths.
+        if (!data.content || data.content === "Report not ready.") {
+            reportContainer.innerHTML = '<div class="empty-state"><p>Analysis in progress or no report generated yet.</p></div>';
+        } else {
+            reportContainer.innerHTML = marked.parse(data.content);
         }
-
     } catch (e) {
         reportContainer.innerHTML = '<p class="error">Failed to load report.</p>';
-        console.error(e);
     }
 }
 
+// --- Gallery Logic ---
+let galleryImages = [];
+let currentImageIndex = 0;
+
 async function loadGallery() {
     if (!currentSessionId) return;
-
-    // Switch to gallery view logic if we were already there
-    // But this is just data loading
     try {
         const res = await fetch(`/api/figures?session_id=${currentSessionId}`);
         const data = await res.json();
 
-        const galleryGrid = document.getElementById('galleryContainer');
-        if (!data.figures || data.figures.length === 0) {
-            galleryGrid.innerHTML = `
-                <div class="empty-state">
-                    <i class="fa-solid fa-images"></i>
-                    <p>No images generated in this session.</p>
-                </div>
-            `;
-            return;
-        }
-
-        let html = '';
-        data.figures.forEach(fig => {
-            html += `
-                <div class="gallery-card">
-                    <div class="img-wrapper">
-                        <img src="${fig.web_url}" alt="${fig.filename}" onclick="window.open('${fig.web_url}', '_blank')">
-                    </div>
-                    <div class="card-content">
-                        <h4>${fig.filename}</h4>
-                        <p class="desc">${fig.description || 'No description'}</p>
-                        ${fig.analysis ? `<div class="analysis-box"><i class="fa-solid fa-magnifying-glass"></i> ${fig.analysis}</div>` : ''}
-                    </div>
-                </div>
-            `;
-        });
-        galleryGrid.innerHTML = html;
+        galleryImages = data.figures || [];
+        currentImageIndex = 0;
+        renderGalleryImage();
 
     } catch (e) {
         console.error("Gallery load failed", e);
+        document.getElementById('carouselSlide').innerHTML = '<p class="error">Failed to load images.</p>';
     }
 }
 
-// --- Export Report ---
+function renderGalleryImage() {
+    const slide = document.getElementById('carouselSlide');
+    const info = document.getElementById('imageInfo');
+
+    if (galleryImages.length === 0) {
+        slide.innerHTML = '<p class="placeholder-text" style="color:var(--text-secondary);">No images generated in this session.</p>';
+        info.innerHTML = '';
+        return;
+    }
+
+    const img = galleryImages[currentImageIndex];
+
+    // Image
+    slide.innerHTML = `<img src="${img.web_url}" alt="${img.filename}" onclick="window.open('${img.web_url}', '_blank')">`;
+
+    // Info
+    info.innerHTML = `
+        <div class="image-title">${img.filename} (${currentImageIndex + 1}/${galleryImages.length})</div>
+        <div class="image-desc">${img.description || 'No description available.'}</div>
+        ${img.analysis ? `<div style="font-size:0.8rem; margin-top:0.5rem; color:#4B5563; background:#F3F4F6; padding:0.5rem; border-radius:4px;">${img.analysis}</div>` : ''}
+    `;
+}
+
+window.prevImage = function () {
+    if (galleryImages.length === 0) return;
+    currentImageIndex = (currentImageIndex - 1 + galleryImages.length) % galleryImages.length;
+    renderGalleryImage();
+}
+
+window.nextImage = function () {
+    if (galleryImages.length === 0) return;
+    currentImageIndex = (currentImageIndex + 1) % galleryImages.length;
+    renderGalleryImage();
+}
+
+// --- Download Script ---
+window.downloadScript = async function () {
+    if (!currentSessionId) return;
+    const link = document.createElement('a');
+    link.href = `/api/download_script?session_id=${currentSessionId}`;
+    link.download = '';
+    document.body.appendChild(link);
+    link.click();
+    document.body.removeChild(link);
+}
+
 // --- Export Report ---
 window.triggerExport = async function () {
     if (!currentSessionId) {
         alert("No active session to export.");
         return;
     }
-
     const btn = document.getElementById('exportBtn');
-    const originalText = btn.innerHTML;
+    const originalContent = btn.innerHTML;
     btn.innerHTML = '<i class="fa-solid fa-spinner fa-spin"></i> Zipping...';
     btn.disabled = true;
 
     try {
         const url = `/api/export?session_id=${currentSessionId}`;
-        const res = await fetch(url); // Default GET
+        window.open(url, '_blank');
 
-        if (res.ok) {
-            const blob = await res.blob();
-            const downloadUrl = window.URL.createObjectURL(blob);
-            const a = document.createElement('a');
-            a.href = downloadUrl;
-            a.download = `analysis_export_${currentSessionId}.zip`;
-            document.body.appendChild(a);
-            a.click();
-            a.remove();
-            window.URL.revokeObjectURL(downloadUrl);
-        } else {
-            // Try to parse error
-            let errMsg = "Unknown error";
-            try {
-                const err = await res.json();
-                errMsg = err.detail || errMsg;
-            } catch (jsonErr) {
-                errMsg = res.statusText;
-            }
-            alert("Export failed: " + errMsg);
-        }
     } catch (e) {
         alert("Export failed: " + e.message);
     } finally {
-        btn.innerHTML = originalText;
-        btn.disabled = false;
+        setTimeout(() => {
+            btn.innerHTML = originalContent;
+            btn.disabled = false;
+        }, 2000);
     }
 }
 
 // --- Follow-up Chat ---
 window.sendFollowUp = async function () {
     if (!currentSessionId || isRunning) return;
-
     const input = document.getElementById('followUpInput');
     const message = input.value.trim();
     if (!message) return;
 
-    // UI Loading state
-    const btn = document.getElementById('sendFollowUpBtn');
-    btn.disabled = true;
     input.disabled = true;
-
     try {
         const res = await fetch('/api/chat', {
             method: 'POST',
@@ -289,128 +307,128 @@ window.sendFollowUp = async function () {
             startPolling();
             switchTab('logs');
         } else {
-            const err = await res.json();
-            alert('Error: ' + err.detail);
+            alert('Failed to send request');
         }
     } catch (e) {
         console.error(e);
-        alert('Failed to send request');
     } finally {
-        btn.disabled = false;
         input.disabled = false;
     }
 }
 
+// --- History Logic ---
+async function loadHistory() {
+    const list = document.getElementById('historyList');
+    if (!list) return;
 
+    try {
+        const res = await fetch('/api/history');
+        const data = await res.json();
 
-// --- Tabs (Inner) ---
-window.switchTab = function (tabName) {
-    document.querySelectorAll('.tab-btn').forEach(b => b.classList.remove('active'));
-    document.querySelectorAll('.tab-content').forEach(c => c.classList.remove('active'));
+        if (data.history.length === 0) {
+            list.innerHTML = '<div style="padding:0.5rem; font-size:0.8rem; color:#9CA3AF;">No history yet</div>';
+            return;
+        }
 
-    const btn = document.querySelector(`button[onclick="switchTab('${tabName}')"]`);
-    if (btn) btn.classList.add('active');
+        let html = '';
+        data.history.forEach(item => {
+            // item: {id, timestamp, name}
+            const timeStr = item.timestamp.split(' ')[0]; // Just date for compactness
+            html += `
+                <div class="history-item" onclick="loadSession('${item.id}')" id="hist-${item.id}">
+                    <i class="fa-regular fa-clock"></i>
+                    <span>${item.id}</span>
+                </div>
+            `;
+        });
+        list.innerHTML = html;
 
-    const tab = document.getElementById(`${tabName}Tab`);
-    if (tab) tab.classList.add('active');
+    } catch (e) {
+        console.error("Failed to load history", e);
+    }
 }
 
-// --- View Navigation (Outer Sidebar) ---
-window.switchView = function (viewName) {
-    // 1. Update Sidebar Buttons
-    document.querySelectorAll('.nav-btn').forEach(b => b.classList.remove('active'));
-    const navBtn = document.querySelector(`button[onclick="switchView('${viewName}')"]`);
-    if (navBtn) navBtn.classList.add('active');
+window.loadSession = async function (sessionId) {
+    if (isRunning) {
+        alert("Analysis in progress, please wait.");
+        return;
+    }
 
-    // 2. Switch Main Content Sections
-    const viewId = 'view' + viewName.charAt(0).toUpperCase() + viewName.slice(1);
+    currentSessionId = sessionId;
 
-    document.querySelectorAll('.view-section').forEach(v => {
-        // Hide all
-        v.style.display = 'none';
-        v.classList.remove('active');
-    });
+    // Update active class
+    document.querySelectorAll('.history-item').forEach(el => el.classList.remove('active'));
+    const activeItem = document.getElementById(`hist-${sessionId}`);
+    if (activeItem) activeItem.classList.add('active');
 
-    const activeView = document.getElementById(viewId);
-    if (activeView) {
-        // Analysis view uses flex for layout (logs scrolling), others use block
-        if (viewName === 'analysis') {
-            activeView.style.display = 'flex';
-            activeView.style.flexDirection = 'column';
-        } else {
-            activeView.style.display = 'block';
-            // If switching to gallery, reload it if session exists
-            if (viewName === 'gallery' && currentSessionId) {
-                loadGallery();
+    // Reset UI
+    logOutput.innerText = "Loading session data...";
+    reportContainer.innerHTML = "";
+    if (downloadScriptBtn) downloadScriptBtn.classList.add('hidden');
+
+    // Fetch Status to get logs and check report
+    try {
+        const res = await fetch(`/api/status?session_id=${sessionId}`);
+        if (res.ok) {
+            const data = await res.json();
+            logOutput.innerText = data.log || "No logs available.";
+
+            // Auto scroll log
+            const logTab = document.getElementById('logsTab');
+            if (logTab) logTab.scrollTop = logTab.scrollHeight;
+
+            if (data.has_report) {
+                await loadReport();
+                // Check if script exists
+                if (data.script_path && downloadScriptBtn) {
+                    downloadScriptBtn.classList.remove('hidden');
+                    downloadScriptBtn.style.display = 'inline-flex';
+                }
+                switchTab('report');
+            } else {
+                switchTab('logs');
             }
         }
-        activeView.classList.add('active');
-    }
-
-    // 3. Toggle Sidebar Controls (only show Analysis Controls in analysis view)
-    const analysisControls = document.getElementById('analysisControls');
-    if (analysisControls) {
-        analysisControls.style.display = (viewName === 'analysis') ? 'block' : 'none';
+    } catch (e) {
+        logOutput.innerText = "Error loading session.";
     }
 }
 
-// --- Tool Functions ---
-window.triggerMerge = async function () {
-    const sourceDir = document.getElementById('mergeSource').value;
-    const resultDiv = document.getElementById('mergeResult');
+// Initialize
+document.addEventListener('DOMContentLoaded', () => {
+    loadHistory();
+});
 
-    resultDiv.innerHTML = '<i class="fa-solid fa-spinner fa-spin"></i> Merging...';
+// --- Navigation ---
+// No-op for switchView as sidebar is simplified
+window.switchView = function (viewName) {
+    console.log("View switch requested:", viewName);
+}
 
-    try {
-        const res = await fetch('/api/tools/merge', {
-            method: 'POST',
-            headers: { 'Content-Type': 'application/json' },
-            body: JSON.stringify({ source_dir: sourceDir, output_filename: 'merged_output.csv' })
+window.switchTab = function (tabName) {
+    // Buttons
+    document.querySelectorAll('.tab').forEach(t => t.classList.remove('active'));
+    // Content
+    ['logs', 'report', 'gallery'].forEach(name => {
+        const content = document.getElementById(`${name}Tab`);
+        if (content) content.classList.add('hidden');
+
+        // 找到对应的 Tab 按钮并激活
+        // 这里假设 Tab 按钮的 onclick 包含 tabName
+        document.querySelectorAll('.tab').forEach(btn => {
+            if (btn.getAttribute('onclick') && btn.getAttribute('onclick').includes(`'${tabName}'`)) {
+                btn.classList.add('active');
+            }
         });
-        const data = await res.json();
-        if (data.status === 'success') {
-            resultDiv.innerHTML = `<span style="color:var(--success)"><i class="fa-solid fa-check"></i> ${data.message}</span>`;
-        } else {
-            resultDiv.innerHTML = `<span style="color:var(--warning)">${data.message}</span>`;
-        }
-    } catch (e) {
-        resultDiv.innerHTML = `<span style="color:red">Error: ${e.message}</span>`;
-    }
-}
-
-window.triggerSort = async function () {
-    const targetFile = document.getElementById('sortTarget').value;
-    const resultDiv = document.getElementById('sortResult');
-
-    resultDiv.innerHTML = '<i class="fa-solid fa-spinner fa-spin"></i> Sorting...';
-
-    try {
-        const res = await fetch('/api/tools/sort', {
-            method: 'POST',
-            headers: { 'Content-Type': 'application/json' },
-            body: JSON.stringify({ target_file: targetFile })
-        });
-        const data = await res.json();
-        if (data.status === 'success') {
-            resultDiv.innerHTML = `<span style="color:var(--success)"><i class="fa-solid fa-check"></i> ${data.message}</span>`;
-        } else {
-            resultDiv.innerHTML = `<span style="color:var(--warning)">${data.message}</span>`;
-        }
-    } catch (e) {
-        resultDiv.innerHTML = `<span style="color:red">Error: ${e.message}</span>`;
-    }
-}
-
-// --- Help Functions ---
-window.fetchHelp = async function () {
-    const container = document.getElementById('helpContainer');
-    container.innerHTML = 'Loading...';
-
-    try {
-        const res = await fetch('/api/help/troubleshooting');
-        const data = await res.json();
-        container.innerHTML = marked.parse(data.content);
-    } catch (e) {
-        container.innerHTML = 'Failed to load guide.';
+    });
+
+    // Valid tabs logic
+    if (tabName === 'logs') {
+        document.getElementById('logsTab').classList.remove('hidden');
+    } else if (tabName === 'report') {
+        document.getElementById('reportTab').classList.remove('hidden');
+    } else if (tabName === 'gallery') {
+        document.getElementById('galleryTab').classList.remove('hidden');
+        if (currentSessionId) loadGallery();
     }
 }
diff --git a/web/static/style.css b/web/static/style.css
deleted file mode 100644
index 7ba8852..0000000
--- a/web/static/style.css
+++ /dev/null
@@ -1,501 +0,0 @@
-@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');
-
-:root {
-    /* Nebula Theme Palette */
-    --bg-deep: #020617;
-    --bg-secondary: #0f172a;
-
-    --sidebar-bg: rgba(15, 23, 42, 0.6);
-    --card-bg: rgba(30, 41, 59, 0.3);
-    --glass-border: 1px solid rgba(148, 163, 184, 0.08);
-
-    --primary-color: #6366f1;
-    --primary-glow: #6366f1aa;
-    --accent-color: #0ea5e9;
-
-    --text-main: #f8fafc;
-    --text-muted: #94a3b8;
-
-    --success: #10b981;
-    --warning: #f59e0b;
-    --danger: #ef4444;
-
-    --radius-lg: 1rem;
-    --radius-md: 0.75rem;
-    --radius-sm: 0.5rem;
-}
-
-* {
-    box-sizing: border-box;
-    margin: 0;
-    padding: 0;
-}
-
-body {
-    font-family: 'Inter', sans-serif;
-    background-color: var(--bg-deep);
-    background-image:
-        radial-gradient(circle at 15% 50%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
-        radial-gradient(circle at 85% 30%, rgba(14, 165, 233, 0.08) 0%, transparent 50%);
-    color: var(--text-main);
-    height: 100vh;
-    overflow: hidden;
-    display: flex;
-    justify-content: center;
-    align-items: center;
-}
-
-.app-container {
-    display: flex;
-    height: 96vh;
-    width: 98vw;
-    gap: 1rem;
-    border-radius: var(--radius-lg);
-    overflow: hidden;
-}
-
-/* --- Floating Sidebar --- */
-.sidebar {
-    width: 280px;
-    background: var(--sidebar-bg);
-    backdrop-filter: blur(20px);
-    -webkit-backdrop-filter: blur(20px);
-    border: var(--glass-border);
-    border-radius: var(--radius-lg);
-    padding: 1.5rem;
-    display: flex;
-    flex-direction: column;
-    gap: 2rem;
-    transition: all 0.3s ease;
-    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
-}
-
-.brand {
-    display: flex;
-    align-items: center;
-    gap: 0.75rem;
-    padding: 0.5rem 0.5rem 1rem 0.5rem;
-    border-bottom: var(--glass-border);
-}
-
-.brand i {
-    font-size: 1.75rem;
-    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
-    -webkit-background-clip: text;
-    background-clip: text;
-    -webkit-text-fill-color: transparent;
-    filter: drop-shadow(0 0 10px rgba(99, 102, 241, 0.5));
-}
-
-.brand h1 {
-    font-family: 'Outfit', sans-serif;
-    font-size: 1.5rem;
-    font-weight: 700;
-    letter-spacing: -0.02em;
-    background: linear-gradient(to right, #fff, #94a3b8);
-    -webkit-background-clip: text;
-    background-clip: text;
-    -webkit-text-fill-color: transparent;
-}
-
-/* Nav Buttons */
-.nav-btn {
-    width: 100%;
-    padding: 0.875rem 1rem;
-    border: none;
-    background: transparent;
-    color: var(--text-muted);
-    font-family: 'Outfit', sans-serif;
-    font-weight: 500;
-    text-align: left;
-    cursor: pointer;
-    border-radius: var(--radius-md);
-    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
-    display: flex;
-    align-items: center;
-    gap: 0.75rem;
-    font-size: 0.95rem;
-}
-
-.nav-btn i {
-    font-size: 1.1rem;
-    transition: transform 0.2s;
-}
-
-.nav-btn:hover {
-    background: rgba(255, 255, 255, 0.03);
-    color: var(--text-main);
-    transform: translateX(4px);
-}
-
-.nav-btn.active {
-    background: linear-gradient(90deg, rgba(99, 102, 241, 0.1), transparent);
-    color: var(--primary-color);
-    border-left: 3px solid var(--primary-color);
-    border-radius: 4px var(--radius-md) var(--radius-md) 4px;
-}
-
-.nav-btn.active i {
-    color: var(--primary-color);
-    transform: scale(1.1);
-}
-
-/* --- Main Content --- */
-.main-content {
-    flex: 1;
-    background: rgba(15, 23, 42, 0.4);
-    backdrop-filter: blur(12px);
-    border: var(--glass-border);
-    border-radius: var(--radius-lg);
-    padding: 2rem;
-    display: flex;
-    flex-direction: column;
-    overflow: hidden;
-    position: relative;
-    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
-}
-
-/* Controls */
-.control-group-wrapper {
-    display: flex;
-    flex-direction: column;
-    gap: 1.5rem;
-}
-
-.control-group h3 {
-    font-family: 'Outfit', sans-serif;
-    font-size: 0.75rem;
-    color: #475569;
-    text-transform: uppercase;
-    letter-spacing: 0.1em;
-    font-weight: 700;
-    margin-bottom: 0.75rem;
-}
-
-/* Upload Zone */
-.upload-zone {
-    border: 1px dashed rgba(255, 255, 255, 0.1);
-    border-radius: 1rem;
-    padding: 1.5rem;
-    text-align: center;
-    transition: all 0.3s ease;
-    background: rgba(2, 6, 23, 0.3);
-    position: relative;
-    overflow: hidden;
-}
-
-.upload-zone::before {
-    content: '';
-    position: absolute;
-    inset: 0;
-    background: radial-gradient(circle at center, rgba(99, 102, 241, 0.1), transparent 70%);
-    opacity: 0;
-    transition: opacity 0.3s;
-}
-
-.upload-zone:hover::before {
-    opacity: 1;
-}
-
-.upload-zone.dragover {
-    border-color: var(--primary-color);
-    box-shadow: 0 0 20px rgba(99, 102, 241, 0.2);
-}
-
-.upload-zone i {
-    font-size: 2rem;
-    background: linear-gradient(to bottom, #94a3b8, #475569);
-    -webkit-background-clip: text;
-    background-clip: text;
-    -webkit-text-fill-color: transparent;
-    margin-bottom: 0.5rem;
-}
-
-.file-list {
-    margin-top: 0.5rem;
-    display: flex;
-    flex-direction: column;
-    gap: 0.25rem;
-}
-
-/* Buttons */
-.btn {
-    width: 100%;
-    padding: 0.875rem;
-    border-radius: var(--radius-md);
-    border: none;
-    cursor: pointer;
-    font-family: 'Outfit', sans-serif;
-    font-weight: 600;
-    font-size: 0.9rem;
-    display: flex;
-    align-items: center;
-    justify-content: center;
-    gap: 0.5rem;
-    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
-    position: relative;
-    overflow: hidden;
-}
-
-.btn.primary {
-    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover, #4f46e5));
-    color: white;
-    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
-}
-
-.btn.primary:hover {
-    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
-    transform: translateY(-1px);
-}
-
-.btn.primary::after {
-    content: '';
-    position: absolute;
-    top: 0;
-    left: -100%;
-    width: 100%;
-    height: 100%;
-    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
-    transition: 0.5s;
-}
-
-.btn.primary:hover::after {
-    left: 100%;
-}
-
-.btn.secondary {
-    background: rgba(255, 255, 255, 0.05);
-    color: var(--text-main);
-    border: 1px solid rgba(255, 255, 255, 0.05);
-}
-
-.btn.secondary:hover {
-    background: rgba(255, 255, 255, 0.1);
-    border-color: rgba(255, 255, 255, 0.2);
-}
-
-/* Inputs */
-textarea,
-input[type="text"] {
-    width: 100%;
-    background: rgba(2, 6, 23, 0.3);
-    border: 1px solid rgba(255, 255, 255, 0.05);
-    border-radius: var(--radius-md);
-    padding: 1rem;
-    color: var(--text-main);
-    font-family: 'Inter', sans-serif;
-    font-size: 0.9rem;
-    transition: all 0.2s;
-}
-
-textarea:focus,
-input[type="text"]:focus {
-    outline: none;
-    border-color: var(--primary-color);
-    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.1);
-}
-
-/* Tabs */
-.tabs {
-    display: flex;
-    gap: 0.5rem;
-    margin-bottom: 1.5rem;
-    background: rgba(2, 6, 23, 0.2);
-    padding: 0.3rem;
-    border-radius: var(--radius-lg);
-    width: fit-content;
-}
-
-.tab-btn {
-    padding: 0.6rem 1.25rem;
-    border: none;
-    background: transparent;
-    color: var(--text-muted);
-    font-family: 'Outfit', sans-serif;
-    font-weight: 500;
-    font-size: 0.85rem;
-    border-radius: var(--radius-md);
-    cursor: pointer;
-    transition: all 0.2s;
-    display: flex;
-    align-items: center;
-    gap: 0.5rem;
-}
-
-.tab-btn:hover {
-    color: var(--text-main);
-}
-
-.tab-btn.active {
-    background: rgba(255, 255, 255, 0.08);
-    color: white;
-    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
-}
-
-/* Terminal / Log Window */
-.terminal-window {
-    background: #09090b;
-    border-radius: var(--radius-lg);
-    padding: 1.5rem;
-    flex: 1;
-    overflow-y: auto;
-    border: 1px solid rgba(255, 255, 255, 0.05);
-    font-family: 'JetBrains Mono', monospace;
-    font-size: 0.85rem;
-    color: #22c55e;
-    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5);
-    min-height: 0;
-}
-
-.terminal-window::-webkit-scrollbar {
-    width: 8px;
-}
-
-.terminal-window::-webkit-scrollbar-thumb {
-    background: rgba(255, 255, 255, 0.1);
-    border-radius: 4px;
-}
-
-/* Report Container */
-#reportContainer {
-    background: rgba(255, 255, 255, 0.95);
-    color: #1e293b;
-    border-radius: var(--radius-lg);
-    padding: 2.5rem;
-    flex: 1;
-    overflow-y: auto;
-    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
-}
-
-.empty-state {
-    display: flex;
-    flex-direction: column;
-    align-items: center;
-    justify-content: center;
-    height: 100%;
-    color: rgba(255, 255, 255, 0.2);
-    gap: 1rem;
-}
-
-.empty-state i {
-    font-size: 4rem;
-}
-
-/* Follow-up Chat */
-.chat-input-container {
-    margin-top: 1rem;
-    background: rgba(2, 6, 23, 0.4);
-    border: var(--glass-border);
-    border-radius: var(--radius-lg);
-    padding: 0.5rem;
-}
-
-.input-wrapper {
-    display: flex;
-    gap: 0.5rem;
-    align-items: flex-end;
-}
-
-#followUpInput {
-    background: transparent;
-    border: none;
-    height: 50px;
-    padding: 0.8rem;
-    resize: none;
-    box-shadow: none;
-}
-
-#sendFollowUpBtn {
-    width: 50px;
-    height: 50px;
-    border-radius: var(--radius-md);
-    padding: 0;
-    flex-shrink: 0;
-}
-
-/* Gallery Grid */
-.gallery-grid {
-    display: grid;
-    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
-    gap: 1.5rem;
-    padding-bottom: 2rem;
-    overflow-y: auto;
-}
-
-.gallery-card {
-    background: rgba(255, 255, 255, 0.03);
-    border: var(--glass-border);
-    border-radius: var(--radius-lg);
-    overflow: hidden;
-    transition: all 0.3s;
-}
-
-.gallery-card:hover {
-    transform: translateY(-4px);
-    border-color: var(--primary-color);
-    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
-}
-
-.img-wrapper {
-    height: 180px;
-    overflow: hidden;
-    background: rgba(0, 0, 0, 0.2);
-    cursor: pointer;
-}
-
-.img-wrapper img {
-    width: 100%;
-    height: 100%;
-    object-fit: cover;
-    transition: transform 0.5s;
-}
-
-.img-wrapper:hover img {
-    transform: scale(1.05);
-}
-
-.card-content {
-    padding: 1rem;
-}
-
-.card-content h4 {
-    font-family: 'Outfit', sans-serif;
-    margin-bottom: 0.5rem;
-    font-size: 1rem;
-}
-
-.card-content .desc {
-    color: var(--text-muted);
-    font-size: 0.85rem;
-}
-
-/* Status Dot */
-.status-indicator {
-    margin-top: auto;
-    padding-top: 1.5rem;
-    border-top: 1px solid rgba(255, 255, 255, 0.05);
-    display: flex;
-    align-items: center;
-    gap: 0.75rem;
-    color: var(--text-muted);
-    font-size: 0.85rem;
-}
-
-/* Animations */
-@keyframes fadeIn {
-    from {
-        opacity: 0;
-        transform: translateY(10px);
-    }
-
-    to {
-        opacity: 1;
-        transform: translateY(0);
-    }
-}
-
-.view-section {
-    animation: fadeIn 0.4s ease-out;
-    width: 100%;
-    height: 100%;
-}
\ No newline at end of file