From 7225b72906b0688f461eb2d64993b9fb6640d4eb Mon Sep 17 00:00:00 2001
From: "tao.chen" <93983997+taochen-ct@users.noreply.github.com>
Date: Thu, 27 Aug 2026 12:58:48 +0800
Subject: [PATCH] optimize

---
 README.md                     | 107 +++++++
 audit.go                      | 102 +++++++
 cleaner.go                    |  57 ++++
 embed.go                      |  29 ++
 handlers.go                   | 296 +++++++++++++++++++
 main.go                       | 536 +---------------------------------
 quota.go                      | 112 +++++++
 static/app.css                | 327 +++++++++++++++++++++
 static/{index.html => app.js} | 388 ------------------------
 static/index.html.tpl         |  61 ++++
 10 files changed, 1092 insertions(+), 923 deletions(-)
 create mode 100644 README.md
 create mode 100644 audit.go
 create mode 100644 cleaner.go
 create mode 100644 embed.go
 create mode 100644 handlers.go
 create mode 100644 quota.go
 create mode 100644 static/app.css
 rename static/{index.html => app.js} (60%)
 create mode 100644 static/index.html.tpl

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..b0d567b
--- /dev/null
+++ b/README.md
@@ -0,0 +1,107 @@
+# tmp-upload
+
+一个自托管的临时文件分享服务。上传文件后获得一个下载链接,**24 小时后自动删除**。
+
+* Single binary,no runtime dependencies
+* Built-in web UI (zero external assets)
+* 10 GB default quota (configurable)
+* Daily audit log (optional)
+
+---
+
+## 快速开始
+
+```bash
+go build -o server .
+./server
+# → 浏览器打开 http://localhost:8080
+```
+
+```bash
+# 命令行上传
+curl -F "file=@report.pdf" http://localhost:8080/upload
+# → {"filename":"report.pdf","url":"/download/report-2026-08-27-abc123.pdf","expires_at":"..."}
+```
+
+---
+
+## 配置(命令行 flag)
+
+```text
+-dir        ./data/uploads   上传文件保存目录
+-listen     :8080            HTTP 监听地址
+-ttl        24h              文件过期 TTL
+-scan       1h               清理扫描间隔
+-quota      10737418240      总目录配额(字节,默认 10 GB;0 = 不限)
+-audit-dir  ./data/audit     审计日志目录(每天一个 YYYY-MM-DD.log 文件;空字符串禁用)
+```
+
+示例:把 TTL 改成 1 小时、配额 1 GB:
+
+```bash
+./server -ttl 1h -quota 1073741824
+```
+
+---
+
+## HTTP API
+
+| Method | Path                       | 说明                                       |
+|--------|----------------------------|--------------------------------------------|
+| GET    | `/`                        | Web UI(单 HTML 响应,内联 CSS + JS)        |
+| POST   | `/upload`                  | 上传文件(`multipart/form-data`,字段名 `file`) |
+| GET    | `/files`                   | 列出当前未过期文件                         |
+| GET    | `/download/:filename`      | 下载文件                                   |
+| DELETE | `/files/:filename`         | 删除文件                                   |
+
+---
+
+## 目录结构
+
+```text
+tmp-upload/
+├── main.go                  # 入口、配置、路由注册 (60 行)
+├── embed.go                 # //go:embed + init() 拼接 (29 行)
+├── audit.go                 # 审计日志子系统 (102 行)
+├── quota.go                 # 配额管理 + formatSize (112 行)
+├── handlers.go              # HTTP handlers + DTOs (296 行)
+├── cleaner.go               # TTL 过期清理 (57 行)
+├── audit_test.go            # audit 单元测试
+├── security_test.sh         # HTTP 端到端测试
+├── go.mod / go.sum
+└── static/
+    ├── index.html.tpl       # HTML 骨架 (含 /*EMBED_CSS*/、/*EMBED_JS*/ 占位符)
+    ├── app.css              # CSS (327 行)
+    └── app.js               # JS (486 行)
+```
+
+### 单文件部署说明
+
+`embed.go` 用 `//go:embed` 把三个静态文件全部编入二进制,
+在 `init()` 中用 `strings.Replace` 把 CSS/JS 拼到 HTML 骨架里生成 `pageHTML`。
+浏览器访问 `/` 拿到的是**一个**完整 HTML 响应(HTML+CSS+JS 全部内联),
+不产生额外的 `<link>` / `<script src=>` 请求。
+
+---
+
+## 测试
+
+```bash
+go test ./...                    # 单元测试(audit 日志格式)
+bash security_test.sh            # 端到端安全 / 接口测试
+go vet ./...                     # 静态检查
+```
+
+---
+
+## 安全相关
+
+* `DELETE /files/:filename` 不要求鉴权 — 部署时建议放在反代之后或加防火墙
+* 文件名采用时间戳 + 随机串避免冲突与枚举
+* 没有请求体大小硬限制(超出 `-quota` 时上传会失败)
+
+---
+
+## License
+
+Personal project. Use at your own risk.
\ No newline at end of file
diff --git a/audit.go b/audit.go
new file mode 100644
index 0000000..1266a5e
--- /dev/null
+++ b/audit.go
@@ -0,0 +1,102 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"maps"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+// -----------------------------------------------------------------------------
+// 审计日志 (JSON Lines, 一行一条事件, 落盘到 *auditDir/YYYY-MM-DD.log, 跨日自动轮转)
+// -----------------------------------------------------------------------------
+
+var (
+	auditMu     sync.Mutex
+	auditFile   *os.File
+	auditCurDay string // 当前打开文件对应的日期 (YYYY-MM-DD)
+)
+
+// initAudit 创建目录, 打开今天的日志文件
+func initAudit() error {
+	if *auditDir == "" {
+		log.Println("[audit] disabled (audit dir is empty)")
+		return nil
+	}
+	if err := os.MkdirAll(*auditDir, 0o755); err != nil {
+		return fmt.Errorf("create audit dir: %w", err)
+	}
+	if err := openAuditFor(time.Now()); err != nil {
+		return err
+	}
+	log.Printf("[audit] writing to %s/%s.log", *auditDir, auditCurDay)
+	return nil
+}
+
+// openAuditFor 为指定时间打开对应日期的日志文件. 调用方需持有 auditMu.
+func openAuditFor(t time.Time) error {
+	day := t.Format("2006-01-02")
+	if day == auditCurDay && auditFile != nil {
+		return nil
+	}
+	if auditFile != nil {
+		_ = auditFile.Close()
+	}
+	path := filepath.Join(*auditDir, day+".log")
+	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
+	if err != nil {
+		return fmt.Errorf("open %s: %w", path, err)
+	}
+	auditFile = f
+	auditCurDay = day
+	return nil
+}
+
+// audit 写一条审计事件. fields 里的键会合并到事件 JSON 中.
+// 写入失败仅记录到 stdout, 不会影响主流程.
+func audit(c *gin.Context, action string, fields map[string]any) {
+	if *auditDir == "" {
+		return
+	}
+	entry := map[string]any{
+		"ts":      time.Now().Format(time.RFC3339),
+		"action":  action,
+		"ip":      c.ClientIP(),
+		"method":  c.Request.Method,
+		"path":    c.Request.URL.Path,
+		"ua":      c.Request.UserAgent(),
+		"status":  c.Writer.Status(),
+		"latency": time.Since(c.GetTime("t0")).String(),
+	}
+	maps.Copy(entry, fields)
+	b, err := json.Marshal(entry)
+	if err != nil {
+		log.Printf("[audit] marshal err: %v", err)
+		return
+	}
+	b = append(b, '\n')
+
+	auditMu.Lock()
+	defer auditMu.Unlock()
+	if err := openAuditFor(time.Now()); err != nil {
+		log.Printf("[audit] open err: %v", err)
+		return
+	}
+	if _, err := auditFile.Write(b); err != nil {
+		log.Printf("[audit] write err: %v", err)
+	}
+}
+
+// auditT0 记录请求进入时间, 供 audit() 计算 latency
+func auditT0() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.Set("t0", time.Now())
+		c.Next()
+	}
+}
diff --git a/cleaner.go b/cleaner.go
new file mode 100644
index 0000000..b205674
--- /dev/null
+++ b/cleaner.go
@@ -0,0 +1,57 @@
+package main
+
+import (
+	"log"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"github.com/robfig/cron/v3"
+)
+
+// -----------------------------------------------------------------------------
+// TTL 清理器
+// -----------------------------------------------------------------------------
+
+var cleanerOnce sync.Once
+
+func startCleaner() {
+	cleanerOnce.Do(func() {
+		if err := os.MkdirAll(*uploadDir, 0o755); err != nil {
+			log.Fatalf("create upload dir failed: %v", err)
+		}
+		c := cron.New()
+		_, err := c.AddFunc("@every "+scanEvery.String(), func() {
+			now := time.Now()
+			removed := 0
+			var removedBytes int64
+			_ = filepath.Walk(*uploadDir, func(path string, info os.FileInfo, err error) error {
+				if err != nil || info.IsDir() {
+					return nil
+				}
+				if now.Sub(info.ModTime()) > *fileTTL {
+					if rmErr := os.Remove(path); rmErr != nil {
+						log.Printf("[cleaner] remove failed: %s err=%v", path, rmErr)
+					} else {
+						log.Printf("[cleaner] removed: %s (age=%v, size=%s)", path, now.Sub(info.ModTime()), formatSize(info.Size()))
+						removed++
+						removedBytes += info.Size()
+					}
+				}
+				return nil
+			})
+			quotaSub(removedBytes)
+			// 漂移修正: 每小时一次 rescan 校正任何来源不明的字节数偏差
+			rescanQuota()
+			log.Printf("[cleaner] scan done, removed=%d (%s), quota used now=%s",
+				removed, formatSize(removedBytes), formatSize(quotaUsedSnapshot()))
+		})
+		if err != nil {
+			log.Fatalf("add cron job failed: %v", err)
+		}
+		c.Start()
+		log.Printf("[cleaner] started, schedule=@every %s dir=%s ttl=%s",
+			scanEvery, *uploadDir, *fileTTL)
+	})
+}
diff --git a/embed.go b/embed.go
new file mode 100644
index 0000000..dbbc6fc
--- /dev/null
+++ b/embed.go
@@ -0,0 +1,29 @@
+package main
+
+import (
+	"strings"
+
+	_ "embed"
+)
+
+// 嵌入式静态页面 (单文件部署, 把 HTML/CSS/JS 编译进二进制, 无需运行时外部文件)
+
+//go:embed static/index.html.tpl
+var indexTpl []byte
+
+//go:embed static/app.css
+var appCSS []byte
+
+//go:embed static/app.js
+var appJS []byte
+
+// pageHTML is the assembled single-file deployment response.
+// Computed once at startup; same bytes served on every GET /.
+var pageHTML []byte
+
+func init() {
+	s := string(indexTpl)
+	s = strings.Replace(s, "/*EMBED_CSS*/", string(appCSS), 1)
+	s = strings.Replace(s, "/*EMBED_JS*/", string(appJS), 1)
+	pageHTML = []byte(s)
+}
diff --git a/handlers.go b/handlers.go
new file mode 100644
index 0000000..9235884
--- /dev/null
+++ b/handlers.go
@@ -0,0 +1,296 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+// -----------------------------------------------------------------------------
+// 路由处理器
+// -----------------------------------------------------------------------------
+
+type fileResponse struct {
+	Filename   string    `json:"filename"`
+	URL        string    `json:"url"`
+	Size       int64     `json:"size"`
+	UploadedAt time.Time `json:"uploaded_at"`
+	ExpiresAt  time.Time `json:"expires_at"`
+}
+
+func uploadHandler(c *gin.Context) {
+	f, err := c.FormFile(fieldName)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "missing form field 'file'"})
+		audit(c, "upload", gin.H{"file": "", "result": "missing_form_field"})
+		return
+	}
+	// 早 reject: 防止 NUL 字节 + 超长文件名打爆 Stat/Save
+	if strings.ContainsRune(f.Filename, 0) {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "filename contains null byte"})
+		audit(c, "upload", gin.H{"file": f.Filename, "result": "null_byte"})
+		return
+	}
+	// Linux/macOS 路径分量 NAME_MAX = 255 字节
+	if len(f.Filename) > 200 {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "filename too long (max 200 bytes)"})
+		audit(c, "upload", gin.H{"file": f.Filename, "result": "filename_too_long"})
+		return
+	}
+
+	if err := os.MkdirAll(*uploadDir, 0o755); err != nil {
+		log.Printf("[upload] mkdir failed: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		audit(c, "upload", gin.H{"file": f.Filename, "result": "mkdir_failed"})
+		return
+	}
+
+	// 配额检查 (单文件能塞下 + 不会超总配额)
+	if *quota > 0 && f.Size > quotaRemaining() {
+		used, cap_ := quotaSnapshot()
+		c.JSON(http.StatusInsufficientStorage, gin.H{
+			"error": fmt.Sprintf("quota exceeded: %s used / %s cap, file size %s",
+				formatSize(used), formatSize(cap_), formatSize(f.Size)),
+		})
+		audit(c, "upload", gin.H{
+			"file":   f.Filename,
+			"size":   f.Size,
+			"result": "quota_exceeded",
+		})
+		return
+	}
+
+	name := uniqueFilename(*uploadDir, f.Filename)
+	dst := filepath.Join(*uploadDir, name)
+	if err := c.SaveUploadedFile(f, dst); err != nil {
+		log.Printf("[upload] save failed: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		audit(c, "upload", gin.H{"file": f.Filename, "result": "save_failed"})
+		return
+	}
+
+	// 实际写入的字节数可能与 f.Size 略有差异 (SaveUploadedFile 内部处理), 用 stat 拿真实值
+	var written int64 = f.Size
+	if info, statErr := os.Stat(dst); statErr == nil {
+		written = info.Size()
+	}
+	// 原子预留配额, 兜住并发下 pre-save 检查放行的多个请求
+	if !quotaReserve(written) {
+		_ = os.Remove(dst)
+		used, cap_ := quotaSnapshot()
+		c.JSON(http.StatusInsufficientStorage, gin.H{
+			"error": fmt.Sprintf("quota exceeded: %s used / %s cap, file size %s",
+				formatSize(used), formatSize(cap_), formatSize(written)),
+		})
+		audit(c, "upload", gin.H{
+			"file":   name,
+			"size":   written,
+			"result": "quota_exceeded",
+		})
+		return
+	}
+
+	now := time.Now()
+	_ = os.Chtimes(dst, now, now)
+
+	c.JSON(http.StatusOK, fileResponse{
+		Filename:   name,
+		URL:        "/download/" + name,
+		Size:       f.Size,
+		UploadedAt: now,
+		ExpiresAt:  now.Add(*fileTTL),
+	})
+	audit(c, "upload", gin.H{
+		"file":   name, // 落盘后的名字 (可能加了 (1) 后缀)
+		"orig":   f.Filename,
+		"size":   f.Size,
+		"result": "ok",
+	})
+}
+
+// uniqueFilename 把 original 清洗后, 在 dir 中找一个不存在的名字.
+// 规则: 原名 → 原名 (1) → 原名 (2) → ...
+// 例:  report.pdf       -> report.pdf
+//
+//	report.pdf (1)   -> report.pdf (1)
+//	.gitignore       -> .gitignore
+//	.gitignore (1)   -> .gitignore (1)
+func uniqueFilename(dir, original string) string {
+	// 1. 剥离路径组件, 防穿越
+	base := filepath.Base(original)
+	if base == "" || base == "." || base == ".." {
+		base = "file"
+	}
+
+	// 2. 拆分 stem 和 ext, 处理 .gitignore 这类隐藏文件
+	ext := filepath.Ext(base)
+	stem := strings.TrimSuffix(base, ext)
+	if stem == "" {
+		// 整个名字都是扩展名 (如 .gitignore), 把整个当 stem
+		ext = ""
+		stem = base
+	}
+
+	// 3. 依次尝试 base, base (1), base (2), ...
+	// 用 O_CREATE|O_EXCL 原子占位, 解决 TOCTOU 竞态 (20 路并发同名上传必须各自拿到不同名字)
+	// 占位的 0 字节 placeholder 会在 SaveUploadedFile 时被覆盖
+	for i := range 10000 {
+		var candidate string
+		if i == 0 {
+			candidate = base
+		} else {
+			candidate = fmt.Sprintf("%s (%d)%s", stem, i, ext)
+		}
+		p := filepath.Join(dir, candidate)
+		f, err := os.OpenFile(p, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o644)
+		if err == nil {
+			f.Close()
+			return candidate
+		}
+		if !os.IsExist(err) {
+			// 非 "已存在" 错误 (权限/磁盘满等), 兜底用时间戳
+			log.Printf("[uniqueFilename] open err=%v, fallback to ts", err)
+			return fmt.Sprintf("%s (%d)%s", stem, time.Now().UnixNano(), ext)
+		}
+	}
+	return fmt.Sprintf("%s (%d)%s", stem, time.Now().UnixNano(), ext)
+}
+
+func downloadHandler(c *gin.Context) {
+	raw := c.Param("filename")
+	name := filepath.Base(raw)
+	if name == "" || name == "." || name == ".." ||
+		strings.ContainsAny(name, "/\\\x00") {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid filename"})
+		audit(c, "download", gin.H{"file": raw, "result": "invalid_filename"})
+		return
+	}
+	p := filepath.Join(*uploadDir, name)
+
+	info, err := os.Stat(p)
+	if os.IsNotExist(err) {
+		c.JSON(http.StatusNotFound, gin.H{"error": "file not found or expired"})
+		audit(c, "download", gin.H{"file": name, "result": "not_found"})
+		return
+	}
+	if err != nil {
+		log.Printf("[download] stat failed: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		audit(c, "download", gin.H{"file": name, "result": "stat_failed"})
+		return
+	}
+	if info.IsDir() {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "not a file"})
+		audit(c, "download", gin.H{"file": name, "result": "is_dir"})
+		return
+	}
+
+	// 强制下载 + 防 XSS (浏览器不会按扩展名/Content-Type 渲染)
+	c.Header("Content-Disposition", `attachment; filename="`+name+`"`)
+	c.Header("X-Content-Type-Options", "nosniff")
+
+	// 下载即续期
+	now := time.Now()
+	_ = os.Chtimes(p, now, now)
+
+	c.File(p)
+	audit(c, "download", gin.H{
+		"file":   name,
+		"size":   info.Size(),
+		"result": "ok",
+	})
+}
+
+type fileInfo struct {
+	Filename  string    `json:"filename"`
+	URL       string    `json:"url"`
+	Size      int64     `json:"size"`
+	ModTime   time.Time `json:"mod_time"`
+	ExpiresAt time.Time `json:"expires_at"`
+}
+
+func listHandler(c *gin.Context) {
+	entries, err := os.ReadDir(*uploadDir)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	files := make([]fileInfo, 0, len(entries))
+	for _, e := range entries {
+		if e.IsDir() {
+			continue
+		}
+		info, err := e.Info()
+		if err != nil {
+			continue
+		}
+		files = append(files, fileInfo{
+			Filename:  e.Name(),
+			URL:       "/download/" + e.Name(),
+			Size:      info.Size(),
+			ModTime:   info.ModTime(),
+			ExpiresAt: info.ModTime().Add(*fileTTL),
+		})
+	}
+	c.JSON(http.StatusOK, gin.H{
+		"count": len(files),
+		"now":   time.Now(),
+		"ttl":   fileTTL.String(),
+		"quota": func() gin.H {
+			used, cap_ := quotaSnapshot()
+			return gin.H{
+				"used":     used,
+				"cap":      cap_,
+				"used_str": formatSize(used),
+				"cap_str":  formatSize(cap_),
+			}
+		}(),
+		"files": files,
+	})
+}
+
+func deleteHandler(c *gin.Context) {
+	raw := c.Param("filename")
+	name := filepath.Base(raw)
+	if name == "" || name == "." || name == ".." ||
+		strings.ContainsAny(name, "/\\\x00") {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid filename"})
+		audit(c, "delete", gin.H{"file": raw, "result": "invalid_filename"})
+		return
+	}
+	p := filepath.Join(*uploadDir, name)
+
+	info, err := os.Stat(p)
+	if os.IsNotExist(err) {
+		c.JSON(http.StatusNotFound, gin.H{"error": "file not found or already deleted"})
+		audit(c, "delete", gin.H{"file": name, "result": "not_found"})
+		return
+	}
+	if err != nil {
+		log.Printf("[delete] stat failed: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		audit(c, "delete", gin.H{"file": name, "result": "stat_failed"})
+		return
+	}
+	if info.IsDir() {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "not a file"})
+		audit(c, "delete", gin.H{"file": name, "result": "is_dir"})
+		return
+	}
+
+	if err := os.Remove(p); err != nil {
+		log.Printf("[delete] remove failed: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		audit(c, "delete", gin.H{"file": name, "result": "remove_failed"})
+		return
+	}
+	quotaSub(info.Size())
+	c.JSON(http.StatusOK, gin.H{"deleted": name})
+	audit(c, "delete", gin.H{"file": name, "size": info.Size(), "result": "ok"})
+}
diff --git a/main.go b/main.go
index 1d339cc..4683548 100644
--- a/main.go
+++ b/main.go
@@ -1,28 +1,14 @@
 package main
 
 import (
-	_ "embed"
-	"encoding/json"
 	"flag"
-	"fmt"
 	"log"
-	"maps"
 	"net/http"
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
 	"time"
 
 	"github.com/gin-gonic/gin"
-	"github.com/robfig/cron/v3"
 )
 
-// 嵌入式静态页面 (单文件部署, 把 HTML 编译进二进制, 无需运行时外部文件)
-//
-//go:embed static/index.html
-var indexHTML []byte
-
 // -----------------------------------------------------------------------------
 // 配置 (可被命令行参数覆盖)
 // -----------------------------------------------------------------------------
@@ -36,522 +22,10 @@ var (
 	quota     = flag.Int64("quota", 10<<30, "总目录配额 (字节, 默认 10GB, 0=不限)")
 )
 
-// -----------------------------------------------------------------------------
-// 路由处理器
-// -----------------------------------------------------------------------------
-
 const (
 	fieldName = "file"
 )
 
-type fileResponse struct {
-	Filename   string    `json:"filename"`
-	URL        string    `json:"url"`
-	Size       int64     `json:"size"`
-	UploadedAt time.Time `json:"uploaded_at"`
-	ExpiresAt  time.Time `json:"expires_at"`
-}
-
-// -----------------------------------------------------------------------------
-// 审计日志 (JSON Lines, 一行一条事件, 落盘到 *auditDir/YYYY-MM-DD.log, 跨日自动轮转)
-// -----------------------------------------------------------------------------
-
-var (
-	auditMu     sync.Mutex
-	auditFile   *os.File
-	auditCurDay string // 当前打开文件对应的日期 (YYYY-MM-DD)
-)
-
-// initAudit 创建目录, 打开今天的日志文件
-func initAudit() error {
-	if *auditDir == "" {
-		log.Println("[audit] disabled (audit dir is empty)")
-		return nil
-	}
-	if err := os.MkdirAll(*auditDir, 0o755); err != nil {
-		return fmt.Errorf("create audit dir: %w", err)
-	}
-	if err := openAuditFor(time.Now()); err != nil {
-		return err
-	}
-	log.Printf("[audit] writing to %s/%s.log", *auditDir, auditCurDay)
-	return nil
-}
-
-// openAuditFor 为指定时间打开对应日期的日志文件. 调用方需持有 auditMu.
-func openAuditFor(t time.Time) error {
-	day := t.Format("2006-01-02")
-	if day == auditCurDay && auditFile != nil {
-		return nil
-	}
-	if auditFile != nil {
-		_ = auditFile.Close()
-	}
-	path := filepath.Join(*auditDir, day+".log")
-	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
-	if err != nil {
-		return fmt.Errorf("open %s: %w", path, err)
-	}
-	auditFile = f
-	auditCurDay = day
-	return nil
-}
-
-// audit 写一条审计事件. fields 里的键会合并到事件 JSON 中.
-// 写入失败仅记录到 stdout, 不会影响主流程.
-func audit(c *gin.Context, action string, fields map[string]any) {
-	if *auditDir == "" {
-		return
-	}
-	entry := map[string]any{
-		"ts":      time.Now().Format(time.RFC3339),
-		"action":  action,
-		"ip":      c.ClientIP(),
-		"method":  c.Request.Method,
-		"path":    c.Request.URL.Path,
-		"ua":      c.Request.UserAgent(),
-		"status":  c.Writer.Status(),
-		"latency": time.Since(c.GetTime("t0")).String(),
-	}
-	maps.Copy(entry, fields)
-	b, err := json.Marshal(entry)
-	if err != nil {
-		log.Printf("[audit] marshal err: %v", err)
-		return
-	}
-	b = append(b, '\n')
-
-	auditMu.Lock()
-	defer auditMu.Unlock()
-	if err := openAuditFor(time.Now()); err != nil {
-		log.Printf("[audit] open err: %v", err)
-		return
-	}
-	if _, err := auditFile.Write(b); err != nil {
-		log.Printf("[audit] write err: %v", err)
-	}
-}
-
-// -----------------------------------------------------------------------------
-// 配额 (总目录字节数限制, 默认 10GB, 0=不限)
-// -----------------------------------------------------------------------------
-
-var (
-	quotaMu   sync.Mutex
-	quotaUsed int64 // 当前目录已用字节数
-)
-
-// initQuota 启动时扫描目录, 初始化配额计数
-func initQuota() {
-	if *quota <= 0 {
-		log.Printf("[quota] disabled")
-		return
-	}
-	rescanQuota()
-	log.Printf("[quota] %s / %s", formatSize(quotaUsed), formatSize(*quota))
-}
-
-// rescanQuota 重新扫描目录并重置计数. 调用频率低 (启动 + 清理器每次跑完), 用来修正漂移.
-func rescanQuota() {
-	quotaMu.Lock()
-	defer quotaMu.Unlock()
-	var total int64
-	_ = filepath.Walk(*uploadDir, func(_ string, info os.FileInfo, err error) error {
-		if err != nil || info.IsDir() {
-			return nil
-		}
-		total += info.Size()
-		return nil
-	})
-	quotaUsed = total
-}
-
-// quotaSnapshot 原子返回 used/cap
-func quotaSnapshot() (used, cap_ int64) {
-	quotaMu.Lock()
-	defer quotaMu.Unlock()
-	return quotaUsed, *quota
-}
-
-// quotaRemaining 返回剩余可上传字节数. quota<=0 时返回 math.MaxInt64.
-func quotaRemaining() int64 {
-	quotaMu.Lock()
-	defer quotaMu.Unlock()
-	if *quota <= 0 {
-		return 1 << 62
-	}
-	return *quota - quotaUsed
-}
-
-// quotaReserve 原子地预留 n 字节配额: 超限返回 false, 否则扣减并返回 true.
-func quotaReserve(n int64) bool {
-	quotaMu.Lock()
-	defer quotaMu.Unlock()
-	if *quota > 0 && quotaUsed+n > *quota {
-		return false
-	}
-	quotaUsed += n
-	return true
-}
-
-func quotaSub(n int64) {
-	if n <= 0 {
-		return
-	}
-	quotaMu.Lock()
-	quotaUsed -= n
-	if quotaUsed < 0 { // 漂移防护
-		quotaUsed = 0
-	}
-	quotaMu.Unlock()
-}
-
-// formatSize 字节 → 人类可读
-func formatSize(b int64) string {
-	const (
-		KB = 1 << 10
-		MB = 1 << 20
-		GB = 1 << 30
-		TB = 1 << 40
-	)
-	switch {
-	case b >= TB:
-		return fmt.Sprintf("%.2f TB", float64(b)/TB)
-	case b >= GB:
-		return fmt.Sprintf("%.2f GB", float64(b)/GB)
-	case b >= MB:
-		return fmt.Sprintf("%.2f MB", float64(b)/MB)
-	case b >= KB:
-		return fmt.Sprintf("%.2f KB", float64(b)/KB)
-	default:
-		return fmt.Sprintf("%d B", b)
-	}
-}
-
-func uploadHandler(c *gin.Context) {
-	f, err := c.FormFile(fieldName)
-	if err != nil {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "missing form field 'file'"})
-		audit(c, "upload", gin.H{"file": "", "result": "missing_form_field"})
-		return
-	}
-	// 早 reject: 防止 NUL 字节 + 超长文件名打爆 Stat/Save
-	if strings.ContainsRune(f.Filename, 0) {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "filename contains null byte"})
-		audit(c, "upload", gin.H{"file": f.Filename, "result": "null_byte"})
-		return
-	}
-	// Linux/macOS 路径分量 NAME_MAX = 255 字节
-	if len(f.Filename) > 200 {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "filename too long (max 200 bytes)"})
-		audit(c, "upload", gin.H{"file": f.Filename, "result": "filename_too_long"})
-		return
-	}
-
-	if err := os.MkdirAll(*uploadDir, 0o755); err != nil {
-		log.Printf("[upload] mkdir failed: %v", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
-		audit(c, "upload", gin.H{"file": f.Filename, "result": "mkdir_failed"})
-		return
-	}
-
-	// 配额检查 (单文件能塞下 + 不会超总配额)
-	if *quota > 0 && f.Size > quotaRemaining() {
-		used, cap_ := quotaSnapshot()
-		c.JSON(http.StatusInsufficientStorage, gin.H{
-			"error": fmt.Sprintf("quota exceeded: %s used / %s cap, file size %s",
-				formatSize(used), formatSize(cap_), formatSize(f.Size)),
-		})
-		audit(c, "upload", gin.H{
-			"file":   f.Filename,
-			"size":   f.Size,
-			"result": "quota_exceeded",
-		})
-		return
-	}
-
-	name := uniqueFilename(*uploadDir, f.Filename)
-	dst := filepath.Join(*uploadDir, name)
-	if err := c.SaveUploadedFile(f, dst); err != nil {
-		log.Printf("[upload] save failed: %v", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
-		audit(c, "upload", gin.H{"file": f.Filename, "result": "save_failed"})
-		return
-	}
-
-	// 实际写入的字节数可能与 f.Size 略有差异 (SaveUploadedFile 内部处理), 用 stat 拿真实值
-	var written int64 = f.Size
-	if info, statErr := os.Stat(dst); statErr == nil {
-		written = info.Size()
-	}
-	// 原子预留配额, 兜住并发下 pre-save 检查放行的多个请求
-	if !quotaReserve(written) {
-		_ = os.Remove(dst)
-		used, cap_ := quotaSnapshot()
-		c.JSON(http.StatusInsufficientStorage, gin.H{
-			"error": fmt.Sprintf("quota exceeded: %s used / %s cap, file size %s",
-				formatSize(used), formatSize(cap_), formatSize(written)),
-		})
-		audit(c, "upload", gin.H{
-			"file":   name,
-			"size":   written,
-			"result": "quota_exceeded",
-		})
-		return
-	}
-
-	now := time.Now()
-	_ = os.Chtimes(dst, now, now)
-
-	c.JSON(http.StatusOK, fileResponse{
-		Filename:   name,
-		URL:        "/download/" + name,
-		Size:       f.Size,
-		UploadedAt: now,
-		ExpiresAt:  now.Add(*fileTTL),
-	})
-	audit(c, "upload", gin.H{
-		"file":   name, // 落盘后的名字 (可能加了 (1) 后缀)
-		"orig":   f.Filename,
-		"size":   f.Size,
-		"result": "ok",
-	})
-}
-
-// uniqueFilename 把 original 清洗后, 在 dir 中找一个不存在的名字.
-// 规则: 原名 → 原名 (1) → 原名 (2) → ...
-// 例:  report.pdf       -> report.pdf
-//
-//	report.pdf (1)   -> report.pdf (1)
-//	.gitignore       -> .gitignore
-//	.gitignore (1)   -> .gitignore (1)
-func uniqueFilename(dir, original string) string {
-	// 1. 剥离路径组件, 防穿越
-	base := filepath.Base(original)
-	if base == "" || base == "." || base == ".." {
-		base = "file"
-	}
-
-	// 2. 拆分 stem 和 ext, 处理 .gitignore 这类隐藏文件
-	ext := filepath.Ext(base)
-	stem := strings.TrimSuffix(base, ext)
-	if stem == "" {
-		// 整个名字都是扩展名 (如 .gitignore), 把整个当 stem
-		ext = ""
-		stem = base
-	}
-
-	// 3. 依次尝试 base, base (1), base (2), ...
-	// 用 O_CREATE|O_EXCL 原子占位, 解决 TOCTOU 竞态 (20 路并发同名上传必须各自拿到不同名字)
-	// 占位的 0 字节 placeholder 会在 SaveUploadedFile 时被覆盖
-	for i := range 10000 {
-		var candidate string
-		if i == 0 {
-			candidate = base
-		} else {
-			candidate = fmt.Sprintf("%s (%d)%s", stem, i, ext)
-		}
-		p := filepath.Join(dir, candidate)
-		f, err := os.OpenFile(p, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o644)
-		if err == nil {
-			f.Close()
-			return candidate
-		}
-		if !os.IsExist(err) {
-			// 非 "已存在" 错误 (权限/磁盘满等), 兜底用时间戳
-			log.Printf("[uniqueFilename] open err=%v, fallback to ts", err)
-			return fmt.Sprintf("%s (%d)%s", stem, time.Now().UnixNano(), ext)
-		}
-	}
-	return fmt.Sprintf("%s (%d)%s", stem, time.Now().UnixNano(), ext)
-}
-
-func downloadHandler(c *gin.Context) {
-	raw := c.Param("filename")
-	name := filepath.Base(raw)
-	if name == "" || name == "." || name == ".." ||
-		strings.ContainsAny(name, "/\\\x00") {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid filename"})
-		audit(c, "download", gin.H{"file": raw, "result": "invalid_filename"})
-		return
-	}
-	p := filepath.Join(*uploadDir, name)
-
-	info, err := os.Stat(p)
-	if os.IsNotExist(err) {
-		c.JSON(http.StatusNotFound, gin.H{"error": "file not found or expired"})
-		audit(c, "download", gin.H{"file": name, "result": "not_found"})
-		return
-	}
-	if err != nil {
-		log.Printf("[download] stat failed: %v", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
-		audit(c, "download", gin.H{"file": name, "result": "stat_failed"})
-		return
-	}
-	if info.IsDir() {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "not a file"})
-		audit(c, "download", gin.H{"file": name, "result": "is_dir"})
-		return
-	}
-
-	// 强制下载 + 防 XSS (浏览器不会按扩展名/Content-Type 渲染)
-	c.Header("Content-Disposition", `attachment; filename="`+name+`"`)
-	c.Header("X-Content-Type-Options", "nosniff")
-
-	// 下载即续期
-	now := time.Now()
-	_ = os.Chtimes(p, now, now)
-
-	c.File(p)
-	audit(c, "download", gin.H{
-		"file":   name,
-		"size":   info.Size(),
-		"result": "ok",
-	})
-}
-
-type fileInfo struct {
-	Filename  string    `json:"filename"`
-	URL       string    `json:"url"`
-	Size      int64     `json:"size"`
-	ModTime   time.Time `json:"mod_time"`
-	ExpiresAt time.Time `json:"expires_at"`
-}
-
-func listHandler(c *gin.Context) {
-	entries, err := os.ReadDir(*uploadDir)
-	if err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
-		return
-	}
-	files := make([]fileInfo, 0, len(entries))
-	for _, e := range entries {
-		if e.IsDir() {
-			continue
-		}
-		info, err := e.Info()
-		if err != nil {
-			continue
-		}
-		files = append(files, fileInfo{
-			Filename:  e.Name(),
-			URL:       "/download/" + e.Name(),
-			Size:      info.Size(),
-			ModTime:   info.ModTime(),
-			ExpiresAt: info.ModTime().Add(*fileTTL),
-		})
-	}
-	c.JSON(http.StatusOK, gin.H{
-		"count": len(files),
-		"now":   time.Now(),
-		"ttl":   fileTTL.String(),
-		"quota": func() gin.H {
-			used, cap_ := quotaSnapshot()
-			return gin.H{
-				"used":     used,
-				"cap":      cap_,
-				"used_str": formatSize(used),
-				"cap_str":  formatSize(cap_),
-			}
-		}(),
-		"files": files,
-	})
-}
-
-func deleteHandler(c *gin.Context) {
-	raw := c.Param("filename")
-	name := filepath.Base(raw)
-	if name == "" || name == "." || name == ".." ||
-		strings.ContainsAny(name, "/\\\x00") {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid filename"})
-		audit(c, "delete", gin.H{"file": raw, "result": "invalid_filename"})
-		return
-	}
-	p := filepath.Join(*uploadDir, name)
-
-	info, err := os.Stat(p)
-	if os.IsNotExist(err) {
-		c.JSON(http.StatusNotFound, gin.H{"error": "file not found or already deleted"})
-		audit(c, "delete", gin.H{"file": name, "result": "not_found"})
-		return
-	}
-	if err != nil {
-		log.Printf("[delete] stat failed: %v", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
-		audit(c, "delete", gin.H{"file": name, "result": "stat_failed"})
-		return
-	}
-	if info.IsDir() {
-		c.JSON(http.StatusBadRequest, gin.H{"error": "not a file"})
-		audit(c, "delete", gin.H{"file": name, "result": "is_dir"})
-		return
-	}
-
-	if err := os.Remove(p); err != nil {
-		log.Printf("[delete] remove failed: %v", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
-		audit(c, "delete", gin.H{"file": name, "result": "remove_failed"})
-		return
-	}
-	quotaSub(info.Size())
-	c.JSON(http.StatusOK, gin.H{"deleted": name})
-	audit(c, "delete", gin.H{"file": name, "size": info.Size(), "result": "ok"})
-}
-
-// -----------------------------------------------------------------------------
-// TTL 清理器
-// -----------------------------------------------------------------------------
-
-var cleanerOnce sync.Once
-
-func startCleaner() {
-	cleanerOnce.Do(func() {
-		if err := os.MkdirAll(*uploadDir, 0o755); err != nil {
-			log.Fatalf("create upload dir failed: %v", err)
-		}
-		c := cron.New()
-		_, err := c.AddFunc("@every "+scanEvery.String(), func() {
-			now := time.Now()
-			removed := 0
-			var removedBytes int64
-			_ = filepath.Walk(*uploadDir, func(path string, info os.FileInfo, err error) error {
-				if err != nil || info.IsDir() {
-					return nil
-				}
-				if now.Sub(info.ModTime()) > *fileTTL {
-					if rmErr := os.Remove(path); rmErr != nil {
-						log.Printf("[cleaner] remove failed: %s err=%v", path, rmErr)
-					} else {
-						log.Printf("[cleaner] removed: %s (age=%v, size=%s)", path, now.Sub(info.ModTime()), formatSize(info.Size()))
-						removed++
-						removedBytes += info.Size()
-					}
-				}
-				return nil
-			})
-			quotaSub(removedBytes)
-			// 漂移修正: 每小时一次 rescan 校正任何来源不明的字节数偏差
-			rescanQuota()
-			log.Printf("[cleaner] scan done, removed=%d (%s), quota used now=%s",
-				removed, formatSize(removedBytes), formatSize(quotaUsedSnapshot()))
-		})
-		if err != nil {
-			log.Fatalf("add cron job failed: %v", err)
-		}
-		c.Start()
-		log.Printf("[cleaner] started, schedule=@every %s dir=%s ttl=%s",
-			scanEvery, *uploadDir, *fileTTL)
-	})
-}
-
-// quotaUsedSnapshot 不持锁读, 仅用于 cleaner 自身的日志 (允许轻微漂移)
-func quotaUsedSnapshot() int64 {
-	quotaMu.Lock()
-	defer quotaMu.Unlock()
-	return quotaUsed
-}
-
 // -----------------------------------------------------------------------------
 // main
 // -----------------------------------------------------------------------------
@@ -570,7 +44,7 @@ func main() {
 
 	// 嵌入式首页
 	r.GET("/", func(c *gin.Context) {
-		c.Data(http.StatusOK, "text/html; charset=utf-8", indexHTML)
+		c.Data(http.StatusOK, "text/html; charset=utf-8", pageHTML)
 	})
 
 	// 业务路由
@@ -584,11 +58,3 @@ func main() {
 		log.Fatal(err)
 	}
 }
-
-// auditT0 记录请求进入时间, 供 audit() 计算 latency
-func auditT0() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		c.Set("t0", time.Now())
-		c.Next()
-	}
-}
diff --git a/quota.go b/quota.go
new file mode 100644
index 0000000..c70120b
--- /dev/null
+++ b/quota.go
@@ -0,0 +1,112 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"sync"
+)
+
+// -----------------------------------------------------------------------------
+// 配额 (总目录字节数限制, 默认 10GB, 0=不限)
+// -----------------------------------------------------------------------------
+
+var (
+	quotaMu   sync.Mutex
+	quotaUsed int64 // 当前目录已用字节数
+)
+
+// initQuota 启动时扫描目录, 初始化配额计数
+func initQuota() {
+	if *quota <= 0 {
+		log.Printf("[quota] disabled")
+		return
+	}
+	rescanQuota()
+	log.Printf("[quota] %s / %s", formatSize(quotaUsed), formatSize(*quota))
+}
+
+// rescanQuota 重新扫描目录并重置计数. 调用频率低 (启动 + 清理器每次跑完), 用来修正漂移.
+func rescanQuota() {
+	quotaMu.Lock()
+	defer quotaMu.Unlock()
+	var total int64
+	_ = filepath.Walk(*uploadDir, func(_ string, info os.FileInfo, err error) error {
+		if err != nil || info.IsDir() {
+			return nil
+		}
+		total += info.Size()
+		return nil
+	})
+	quotaUsed = total
+}
+
+// quotaSnapshot 原子返回 used/cap
+func quotaSnapshot() (used, cap_ int64) {
+	quotaMu.Lock()
+	defer quotaMu.Unlock()
+	return quotaUsed, *quota
+}
+
+// quotaRemaining 返回剩余可上传字节数. quota<=0 时返回 math.MaxInt64.
+func quotaRemaining() int64 {
+	quotaMu.Lock()
+	defer quotaMu.Unlock()
+	if *quota <= 0 {
+		return 1 << 62
+	}
+	return *quota - quotaUsed
+}
+
+// quotaReserve 原子地预留 n 字节配额: 超限返回 false, 否则扣减并返回 true.
+func quotaReserve(n int64) bool {
+	quotaMu.Lock()
+	defer quotaMu.Unlock()
+	if *quota > 0 && quotaUsed+n > *quota {
+		return false
+	}
+	quotaUsed += n
+	return true
+}
+
+func quotaSub(n int64) {
+	if n <= 0 {
+		return
+	}
+	quotaMu.Lock()
+	quotaUsed -= n
+	if quotaUsed < 0 { // 漂移防护
+		quotaUsed = 0
+	}
+	quotaMu.Unlock()
+}
+
+// formatSize 字节 → 人类可读
+func formatSize(b int64) string {
+	const (
+		KB = 1 << 10
+		MB = 1 << 20
+		GB = 1 << 30
+		TB = 1 << 40
+	)
+	switch {
+	case b >= TB:
+		return fmt.Sprintf("%.2f TB", float64(b)/TB)
+	case b >= GB:
+		return fmt.Sprintf("%.2f GB", float64(b)/GB)
+	case b >= MB:
+		return fmt.Sprintf("%.2f MB", float64(b)/MB)
+	case b >= KB:
+		return fmt.Sprintf("%.2f KB", float64(b)/KB)
+	default:
+		return fmt.Sprintf("%d B", b)
+	}
+}
+
+// quotaUsedSnapshot 不持锁读, 仅用于 cleaner 自身的日志 (允许轻微漂移)
+func quotaUsedSnapshot() int64 {
+	quotaMu.Lock()
+	defer quotaMu.Unlock()
+	return quotaUsed
+}
diff --git a/static/app.css b/static/app.css
new file mode 100644
index 0000000..0344003
--- /dev/null
+++ b/static/app.css
@@ -0,0 +1,327 @@
+  :root {
+    --bg: #0f1115;
+    --panel: #1a1d24;
+    --panel-2: #232732;
+    --border: #2c3140;
+    --text: #e6e8ee;
+    --text-dim: #8a92a3;
+    --primary: #5b8cff;
+    --primary-hover: #4a7af0;
+    --success: #4ade80;
+    --danger: #f87171;
+    --warning: #fbbf24;
+  }
+  * { box-sizing: border-box; margin: 0; padding: 0; }
+  body {
+    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
+    background: var(--bg);
+    color: var(--text);
+    min-height: 100vh;
+    padding: 40px 20px;
+    line-height: 1.5;
+  }
+  .container { max-width: 880px; margin: 0 auto; }
+  header { text-align: center; margin-bottom: 32px; }
+  h1 {
+    font-size: 28px;
+    font-weight: 600;
+    margin-bottom: 8px;
+    background: linear-gradient(90deg, #5b8cff, #a78bfa);
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+  }
+  .subtitle { color: var(--text-dim); font-size: 14px; }
+  .badge {
+    display: inline-block;
+    margin-left: 8px;
+    padding: 2px 8px;
+    background: var(--panel-2);
+    border: 1px solid var(--border);
+    border-radius: 4px;
+    font-size: 12px;
+    color: var(--warning);
+    -webkit-text-fill-color: var(--warning);
+    vertical-align: middle;
+  }
+
+  .card {
+    background: var(--panel);
+    border: 1px solid var(--border);
+    border-radius: 12px;
+    padding: 24px;
+    margin-bottom: 24px;
+  }
+
+  /* Drop zone */
+  .dropzone {
+    border: 2px dashed var(--border);
+    border-radius: 12px;
+    padding: 48px 24px;
+    text-align: center;
+    cursor: pointer;
+    transition: all 0.2s;
+    background: var(--panel-2);
+    user-select: none;
+  }
+  .dropzone:hover, .dropzone.dragover, .dropzone:focus-visible {
+    border-color: var(--primary);
+    background: rgba(91, 140, 255, 0.05);
+    outline: none;
+  }
+  .dropzone .icon {
+    font-size: 48px;
+    margin-bottom: 12px;
+    color: var(--text-dim);
+  }
+  .dropzone .hint { color: var(--text-dim); font-size: 13px; margin-top: 6px; }
+
+  /* Buttons */
+  .btn {
+    display: inline-block;
+    padding: 10px 20px;
+    background: var(--primary);
+    color: white;
+    border: none;
+    border-radius: 8px;
+    font-size: 14px;
+    font-weight: 500;
+    cursor: pointer;
+    transition: background 0.2s;
+  }
+  .btn:hover { background: var(--primary-hover); }
+  .btn:disabled { background: var(--text-dim); cursor: not-allowed; }
+  .btn.ghost { background: var(--panel-2); }
+  .btn.danger { background: var(--danger); }
+  .btn-row { display: flex; gap: 12px; margin-top: 16px; flex-wrap: wrap; align-items: center; }
+
+  /* Progress */
+  .progress-list { margin-top: 16px; display: flex; flex-direction: column; gap: 8px; }
+  .progress-item {
+    background: var(--panel-2);
+    border: 1px solid var(--border);
+    border-radius: 8px;
+    padding: 12px;
+    transition: opacity 0.3s;
+  }
+  .progress-item.done { border-color: var(--success); }
+  .progress-item.error { border-color: var(--danger); }
+  .progress-item-head {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    font-size: 13px;
+    color: var(--text-dim);
+    margin-bottom: 6px;
+    gap: 8px;
+  }
+  .progress-item-head .name {
+    color: var(--text);
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+    flex: 1;
+    min-width: 0;
+  }
+  .progress-item-head .size-info { font-variant-numeric: tabular-nums; white-space: nowrap; }
+  .progress-item-head .status {
+    width: 20px;
+    height: 20px;
+    border-radius: 50%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 12px;
+    flex-shrink: 0;
+  }
+  .progress-item.done .status { background: var(--success); color: #0f1115; }
+  .progress-item.error .status { background: var(--danger); color: #0f1115; }
+  .progress-bar {
+    height: 4px;
+    background: var(--border);
+    border-radius: 2px;
+    overflow: hidden;
+  }
+  .progress-bar > div {
+    height: 100%;
+    background: var(--primary);
+    width: 0%;
+    transition: width 0.2s;
+  }
+  .progress-item.done .progress-bar > div { background: var(--success); width: 100% !important; }
+  .progress-item.error .progress-bar > div { background: var(--danger); }
+  .progress-item-actions {
+    display: flex;
+    gap: 6px;
+    margin-top: 8px;
+    justify-content: flex-end;
+  }
+  .progress-item-actions button {
+    background: transparent;
+    border: 1px solid var(--border);
+    color: var(--text-dim);
+    border-radius: 4px;
+    padding: 3px 10px;
+    font-size: 12px;
+    cursor: pointer;
+  }
+  .progress-item-actions button:hover { color: var(--text); border-color: var(--text-dim); }
+
+  /* File list */
+  .files-header {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    margin-bottom: 16px;
+    gap: 12px;
+  }
+  .files-header h2 { font-size: 16px; font-weight: 600; }
+  .files-header .meta { font-size: 12px; color: var(--text-dim); }
+
+  /* Quota */
+  .quota-wrap { margin-bottom: 16px; }
+  .quota-row {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    font-size: 12px;
+    color: var(--text-dim);
+    margin-bottom: 4px;
+  }
+  .quota-row .quota-text strong { color: var(--text); font-variant-numeric: tabular-nums; }
+  .quota-row .quota-text.warn strong { color: var(--warning); }
+  .quota-row .quota-text.danger strong { color: var(--danger); }
+  .quota-bar {
+    height: 6px;
+    background: var(--border);
+    border-radius: 3px;
+    overflow: hidden;
+  }
+  .quota-bar > div {
+    height: 100%;
+    background: var(--success);
+    width: 0%;
+    transition: width 0.3s, background 0.3s;
+  }
+  .quota-bar.warn > div { background: var(--warning); }
+  .quota-bar.danger > div { background: var(--danger); }
+  .file-item {
+    display: flex;
+    align-items: center;
+    gap: 12px;
+    padding: 12px;
+    background: var(--panel-2);
+    border: 1px solid var(--border);
+    border-radius: 8px;
+    margin-bottom: 8px;
+  }
+  .file-icon {
+    width: 36px;
+    height: 36px;
+    border-radius: 6px;
+    background: var(--panel);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 18px;
+    flex-shrink: 0;
+  }
+  .file-info { flex: 1; min-width: 0; }
+  .file-name {
+    font-size: 14px;
+    color: var(--text);
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+  .file-meta {
+    font-size: 12px;
+    color: var(--text-dim);
+    margin-top: 2px;
+    display: flex;
+    gap: 10px;
+    flex-wrap: wrap;
+    align-items: center;
+  }
+  .file-meta .ttl { color: var(--warning); font-variant-numeric: tabular-nums; }
+  .file-meta .ttl.danger { color: var(--danger); }
+  .file-actions { display: flex; gap: 6px; }
+  .icon-btn {
+    width: 32px;
+    height: 32px;
+    border-radius: 6px;
+    border: 1px solid var(--border);
+    background: var(--panel);
+    color: var(--text);
+    cursor: pointer;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    transition: all 0.2s;
+    text-decoration: none;
+  }
+  .icon-btn:hover { background: var(--primary); border-color: var(--primary); }
+  .icon-btn.danger:hover { background: var(--danger); border-color: var(--danger); }
+
+  .empty {
+    text-align: center;
+    padding: 40px 20px;
+    color: var(--text-dim);
+    font-size: 14px;
+  }
+  .skeleton {
+    background: linear-gradient(90deg, var(--panel-2) 0%, var(--border) 50%, var(--panel-2) 100%);
+    background-size: 200% 100%;
+    animation: shimmer 1.4s infinite;
+    border-radius: 6px;
+    height: 56px;
+    margin-bottom: 8px;
+  }
+  @keyframes shimmer {
+    0% { background-position: 200% 0; }
+    100% { background-position: -200% 0; }
+  }
+
+  .toast {
+    position: fixed;
+    bottom: 24px;
+    right: 24px;
+    background: var(--panel);
+    border: 1px solid var(--border);
+    border-radius: 8px;
+    padding: 12px 16px;
+    font-size: 14px;
+    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
+    opacity: 0;
+    transform: translateY(8px);
+    transition: all 0.2s;
+    pointer-events: none;
+    z-index: 9999;
+    max-width: 360px;
+  }
+  .toast.show { opacity: 1; transform: translateY(0); }
+  .toast.success { border-left: 3px solid var(--success); }
+  .toast.error { border-left: 3px solid var(--danger); }
+  .toast.info { border-left: 3px solid var(--primary); }
+
+  footer {
+    text-align: center;
+    color: var(--text-dim);
+    font-size: 12px;
+    margin-top: 24px;
+  }
+
+  .total-progress {
+    flex: 1;
+    height: 4px;
+    background: var(--border);
+    border-radius: 2px;
+    overflow: hidden;
+    min-width: 120px;
+  }
+  .total-progress > div {
+    height: 100%;
+    background: var(--primary);
+    width: 0%;
+    transition: width 0.2s;
+  }
+  .total-label { font-size: 12px; color: var(--text-dim); white-space: nowrap; }
diff --git a/static/index.html b/static/app.js
similarity index 60%
rename from static/index.html
rename to static/app.js
index ed5808f..cf3e464 100644
--- a/static/index.html
+++ b/static/app.js
@@ -1,388 +1,3 @@
-<!DOCTYPE html>
-<html lang="zh-CN">
-<head>
-<meta charset="UTF-8" />
-<meta name="viewport" content="width=device-width, initial-scale=1.0" />
-<title>临时文件上传 · TTL 24h</title>
-<style>
-  :root {
-    --bg: #0f1115;
-    --panel: #1a1d24;
-    --panel-2: #232732;
-    --border: #2c3140;
-    --text: #e6e8ee;
-    --text-dim: #8a92a3;
-    --primary: #5b8cff;
-    --primary-hover: #4a7af0;
-    --success: #4ade80;
-    --danger: #f87171;
-    --warning: #fbbf24;
-  }
-  * { box-sizing: border-box; margin: 0; padding: 0; }
-  body {
-    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
-    background: var(--bg);
-    color: var(--text);
-    min-height: 100vh;
-    padding: 40px 20px;
-    line-height: 1.5;
-  }
-  .container { max-width: 880px; margin: 0 auto; }
-  header { text-align: center; margin-bottom: 32px; }
-  h1 {
-    font-size: 28px;
-    font-weight: 600;
-    margin-bottom: 8px;
-    background: linear-gradient(90deg, #5b8cff, #a78bfa);
-    -webkit-background-clip: text;
-    -webkit-text-fill-color: transparent;
-  }
-  .subtitle { color: var(--text-dim); font-size: 14px; }
-  .badge {
-    display: inline-block;
-    margin-left: 8px;
-    padding: 2px 8px;
-    background: var(--panel-2);
-    border: 1px solid var(--border);
-    border-radius: 4px;
-    font-size: 12px;
-    color: var(--warning);
-    -webkit-text-fill-color: var(--warning);
-    vertical-align: middle;
-  }
-
-  .card {
-    background: var(--panel);
-    border: 1px solid var(--border);
-    border-radius: 12px;
-    padding: 24px;
-    margin-bottom: 24px;
-  }
-
-  /* Drop zone */
-  .dropzone {
-    border: 2px dashed var(--border);
-    border-radius: 12px;
-    padding: 48px 24px;
-    text-align: center;
-    cursor: pointer;
-    transition: all 0.2s;
-    background: var(--panel-2);
-    user-select: none;
-  }
-  .dropzone:hover, .dropzone.dragover, .dropzone:focus-visible {
-    border-color: var(--primary);
-    background: rgba(91, 140, 255, 0.05);
-    outline: none;
-  }
-  .dropzone .icon {
-    font-size: 48px;
-    margin-bottom: 12px;
-    color: var(--text-dim);
-  }
-  .dropzone .hint { color: var(--text-dim); font-size: 13px; margin-top: 6px; }
-
-  /* Buttons */
-  .btn {
-    display: inline-block;
-    padding: 10px 20px;
-    background: var(--primary);
-    color: white;
-    border: none;
-    border-radius: 8px;
-    font-size: 14px;
-    font-weight: 500;
-    cursor: pointer;
-    transition: background 0.2s;
-  }
-  .btn:hover { background: var(--primary-hover); }
-  .btn:disabled { background: var(--text-dim); cursor: not-allowed; }
-  .btn.ghost { background: var(--panel-2); }
-  .btn.danger { background: var(--danger); }
-  .btn-row { display: flex; gap: 12px; margin-top: 16px; flex-wrap: wrap; align-items: center; }
-
-  /* Progress */
-  .progress-list { margin-top: 16px; display: flex; flex-direction: column; gap: 8px; }
-  .progress-item {
-    background: var(--panel-2);
-    border: 1px solid var(--border);
-    border-radius: 8px;
-    padding: 12px;
-    transition: opacity 0.3s;
-  }
-  .progress-item.done { border-color: var(--success); }
-  .progress-item.error { border-color: var(--danger); }
-  .progress-item-head {
-    display: flex;
-    justify-content: space-between;
-    align-items: center;
-    font-size: 13px;
-    color: var(--text-dim);
-    margin-bottom: 6px;
-    gap: 8px;
-  }
-  .progress-item-head .name {
-    color: var(--text);
-    overflow: hidden;
-    text-overflow: ellipsis;
-    white-space: nowrap;
-    flex: 1;
-    min-width: 0;
-  }
-  .progress-item-head .size-info { font-variant-numeric: tabular-nums; white-space: nowrap; }
-  .progress-item-head .status {
-    width: 20px;
-    height: 20px;
-    border-radius: 50%;
-    display: flex;
-    align-items: center;
-    justify-content: center;
-    font-size: 12px;
-    flex-shrink: 0;
-  }
-  .progress-item.done .status { background: var(--success); color: #0f1115; }
-  .progress-item.error .status { background: var(--danger); color: #0f1115; }
-  .progress-bar {
-    height: 4px;
-    background: var(--border);
-    border-radius: 2px;
-    overflow: hidden;
-  }
-  .progress-bar > div {
-    height: 100%;
-    background: var(--primary);
-    width: 0%;
-    transition: width 0.2s;
-  }
-  .progress-item.done .progress-bar > div { background: var(--success); width: 100% !important; }
-  .progress-item.error .progress-bar > div { background: var(--danger); }
-  .progress-item-actions {
-    display: flex;
-    gap: 6px;
-    margin-top: 8px;
-    justify-content: flex-end;
-  }
-  .progress-item-actions button {
-    background: transparent;
-    border: 1px solid var(--border);
-    color: var(--text-dim);
-    border-radius: 4px;
-    padding: 3px 10px;
-    font-size: 12px;
-    cursor: pointer;
-  }
-  .progress-item-actions button:hover { color: var(--text); border-color: var(--text-dim); }
-
-  /* File list */
-  .files-header {
-    display: flex;
-    justify-content: space-between;
-    align-items: center;
-    margin-bottom: 16px;
-    gap: 12px;
-  }
-  .files-header h2 { font-size: 16px; font-weight: 600; }
-  .files-header .meta { font-size: 12px; color: var(--text-dim); }
-
-  /* Quota */
-  .quota-wrap { margin-bottom: 16px; }
-  .quota-row {
-    display: flex;
-    justify-content: space-between;
-    align-items: center;
-    font-size: 12px;
-    color: var(--text-dim);
-    margin-bottom: 4px;
-  }
-  .quota-row .quota-text strong { color: var(--text); font-variant-numeric: tabular-nums; }
-  .quota-row .quota-text.warn strong { color: var(--warning); }
-  .quota-row .quota-text.danger strong { color: var(--danger); }
-  .quota-bar {
-    height: 6px;
-    background: var(--border);
-    border-radius: 3px;
-    overflow: hidden;
-  }
-  .quota-bar > div {
-    height: 100%;
-    background: var(--success);
-    width: 0%;
-    transition: width 0.3s, background 0.3s;
-  }
-  .quota-bar.warn > div { background: var(--warning); }
-  .quota-bar.danger > div { background: var(--danger); }
-  .file-item {
-    display: flex;
-    align-items: center;
-    gap: 12px;
-    padding: 12px;
-    background: var(--panel-2);
-    border: 1px solid var(--border);
-    border-radius: 8px;
-    margin-bottom: 8px;
-  }
-  .file-icon {
-    width: 36px;
-    height: 36px;
-    border-radius: 6px;
-    background: var(--panel);
-    display: flex;
-    align-items: center;
-    justify-content: center;
-    font-size: 18px;
-    flex-shrink: 0;
-  }
-  .file-info { flex: 1; min-width: 0; }
-  .file-name {
-    font-size: 14px;
-    color: var(--text);
-    overflow: hidden;
-    text-overflow: ellipsis;
-    white-space: nowrap;
-  }
-  .file-meta {
-    font-size: 12px;
-    color: var(--text-dim);
-    margin-top: 2px;
-    display: flex;
-    gap: 10px;
-    flex-wrap: wrap;
-    align-items: center;
-  }
-  .file-meta .ttl { color: var(--warning); font-variant-numeric: tabular-nums; }
-  .file-meta .ttl.danger { color: var(--danger); }
-  .file-actions { display: flex; gap: 6px; }
-  .icon-btn {
-    width: 32px;
-    height: 32px;
-    border-radius: 6px;
-    border: 1px solid var(--border);
-    background: var(--panel);
-    color: var(--text);
-    cursor: pointer;
-    display: flex;
-    align-items: center;
-    justify-content: center;
-    transition: all 0.2s;
-    text-decoration: none;
-  }
-  .icon-btn:hover { background: var(--primary); border-color: var(--primary); }
-  .icon-btn.danger:hover { background: var(--danger); border-color: var(--danger); }
-
-  .empty {
-    text-align: center;
-    padding: 40px 20px;
-    color: var(--text-dim);
-    font-size: 14px;
-  }
-  .skeleton {
-    background: linear-gradient(90deg, var(--panel-2) 0%, var(--border) 50%, var(--panel-2) 100%);
-    background-size: 200% 100%;
-    animation: shimmer 1.4s infinite;
-    border-radius: 6px;
-    height: 56px;
-    margin-bottom: 8px;
-  }
-  @keyframes shimmer {
-    0% { background-position: 200% 0; }
-    100% { background-position: -200% 0; }
-  }
-
-  .toast {
-    position: fixed;
-    bottom: 24px;
-    right: 24px;
-    background: var(--panel);
-    border: 1px solid var(--border);
-    border-radius: 8px;
-    padding: 12px 16px;
-    font-size: 14px;
-    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
-    opacity: 0;
-    transform: translateY(8px);
-    transition: all 0.2s;
-    pointer-events: none;
-    z-index: 9999;
-    max-width: 360px;
-  }
-  .toast.show { opacity: 1; transform: translateY(0); }
-  .toast.success { border-left: 3px solid var(--success); }
-  .toast.error { border-left: 3px solid var(--danger); }
-  .toast.info { border-left: 3px solid var(--primary); }
-
-  footer {
-    text-align: center;
-    color: var(--text-dim);
-    font-size: 12px;
-    margin-top: 24px;
-  }
-
-  .total-progress {
-    flex: 1;
-    height: 4px;
-    background: var(--border);
-    border-radius: 2px;
-    overflow: hidden;
-    min-width: 120px;
-  }
-  .total-progress > div {
-    height: 100%;
-    background: var(--primary);
-    width: 0%;
-    transition: width 0.2s;
-  }
-  .total-label { font-size: 12px; color: var(--text-dim); white-space: nowrap; }
-</style>
-</head>
-<body>
-<div class="container">
-  <header>
-    <h1>临时文件传输<span class="badge">TTL 24h</span></h1>
-    <div class="subtitle">上传后 24 小时内有效 · 被下载会自动续期 · 自动清理</div>
-  </header>
-
-  <div class="card">
-    <div class="dropzone" id="dropzone" tabindex="0" role="button" aria-label="选择或拖拽文件上传">
-      <div class="icon">⬆</div>
-      <div><strong>点击选择文件</strong> 或将文件拖拽到此处</div>
-      <div class="hint">支持多文件 · 受配额限制</div>
-    </div>
-    <input type="file" id="fileInput" multiple hidden />
-
-    <div class="progress-list" id="progressList"></div>
-
-    <div class="btn-row" id="actionRow" style="display:none">
-      <div class="total-progress" id="totalProgress" style="display:none"><div></div></div>
-      <span class="total-label" id="totalLabel" style="display:none"></span>
-      <button class="btn" id="uploadBtn">开始上传</button>
-      <button class="btn ghost" id="clearBtn">清空</button>
-    </div>
-  </div>
-
-  <div class="card">
-    <div class="files-header">
-      <h2>文件列表</h2>
-      <span class="meta" id="filesMeta">加载中...</span>
-    </div>
-    <div class="quota-wrap" id="quotaWrap" style="display:none">
-      <div class="quota-row">
-        <span class="quota-text" id="quotaText">--</span>
-        <span id="quotaPercent">--</span>
-      </div>
-      <div class="quota-bar" id="quotaBar"><div></div></div>
-    </div>
-    <div id="filesList">
-      <div class="skeleton"></div>
-      <div class="skeleton"></div>
-    </div>
-  </div>
-
-  <footer>每个文件 TTL 默认 24 小时, 后台每小时扫描清理 · 每次下载会重置过期时间</footer>
-</div>
-
-<div class="toast" id="toast"></div>
-
-<script>
 'use strict';
 
 const $ = id => document.getElementById(id);
@@ -869,6 +484,3 @@ function escapeHtml(s) {
 // ---------------------------------------------------------------------------
 loadFiles();
 setInterval(loadFiles, 30000);
-</script>
-</body>
-</html>
diff --git a/static/index.html.tpl b/static/index.html.tpl
new file mode 100644
index 0000000..9af9ca1
--- /dev/null
+++ b/static/index.html.tpl
@@ -0,0 +1,61 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8" />
+<meta name="viewport" content="width=device-width, initial-scale=1.0" />
+<title>临时文件上传 · TTL 24h</title>
+<style>
+/*EMBED_CSS*/</style>
+</head>
+<body>
+<div class="container">
+  <header>
+    <h1>临时文件传输<span class="badge">TTL 24h</span></h1>
+    <div class="subtitle">上传后 24 小时内有效 · 被下载会自动续期 · 自动清理</div>
+  </header>
+
+  <div class="card">
+    <div class="dropzone" id="dropzone" tabindex="0" role="button" aria-label="选择或拖拽文件上传">
+      <div class="icon">⬆</div>
+      <div><strong>点击选择文件</strong> 或将文件拖拽到此处</div>
+      <div class="hint">支持多文件 · 受配额限制</div>
+    </div>
+    <input type="file" id="fileInput" multiple hidden />
+
+    <div class="progress-list" id="progressList"></div>
+
+    <div class="btn-row" id="actionRow" style="display:none">
+      <div class="total-progress" id="totalProgress" style="display:none"><div></div></div>
+      <span class="total-label" id="totalLabel" style="display:none"></span>
+      <button class="btn" id="uploadBtn">开始上传</button>
+      <button class="btn ghost" id="clearBtn">清空</button>
+    </div>
+  </div>
+
+  <div class="card">
+    <div class="files-header">
+      <h2>文件列表</h2>
+      <span class="meta" id="filesMeta">加载中...</span>
+    </div>
+    <div class="quota-wrap" id="quotaWrap" style="display:none">
+      <div class="quota-row">
+        <span class="quota-text" id="quotaText">--</span>
+        <span id="quotaPercent">--</span>
+      </div>
+      <div class="quota-bar" id="quotaBar"><div></div></div>
+    </div>
+    <div id="filesList">
+      <div class="skeleton"></div>
+      <div class="skeleton"></div>
+    </div>
+  </div>
+
+  <footer>每个文件 TTL 默认 24 小时, 后台每小时扫描清理 · 每次下载会重置过期时间</footer>
+</div>
+
+<div class="toast" id="toast"></div>
+
+<script>
+/*EMBED_JS*/</script>
+</body>
+</html>