diff --git a/.env.example b/.env.example
index 2b128d9..bb8e38b 100644
--- a/.env.example
+++ b/.env.example
@@ -35,3 +35,6 @@
 
 # 仅本地开发：设为 true 可绕过登录验证（跳过 /setup，一般无需开启）
 # DEV_BYPASS_ACCESS=false
+
+# 登录人机验证（滑块 / Turnstile / Cap）在后台「设置 → 访问控制」配置，无环境变量。
+# 配置错误无法登录时：docker exec pichost slider（或 npm run slider）恢复为本地滑块。
diff --git a/README.en.md b/README.en.md
index 486d553..e78e403 100644
--- a/README.en.md
+++ b/README.en.md
@@ -42,7 +42,7 @@
 ## Features
 
 - **Drag, click, or Ctrl+V paste** — server-side WebP, Referer hotlink protection
-- **Multi-user** — login with slider captcha, optional registration; users see only their images
+- **Multi-user** — login with slider, Turnstile, or Cap verification; optional registration; users see only their images
 - **Multi-backend storage** — local disk + S3-compatible (R2 / COS / OSS / AWS); hybrid `proxy` / `public` URLs
 - **Gallery** — browse, search, filter by storage/source, grid/list views, batch delete; stats overview and source breakdown
 - **API & Twikoo** — global / per-user tokens; `POST /api/index.php` compatible
diff --git a/README.md b/README.md
index 9691286..87886d2 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@
 ## 特性
 
 - **拖拽 / 点击 / Ctrl+V 粘贴**上传；服务端 WebP 压缩、Referer 防盗链
-- **多用户**：账号密码登录（滑动验证）、可选开放注册；普通用户仅见自己的图片
+- **多用户**：账号密码登录（滑块 / Turnstile / Cap 人机验证）、可选开放注册；普通用户仅见自己的图片
 - **多后端存储**：本地磁盘 + S3 兼容（R2 / COS / OSS / AWS）；混合直链 `proxy` / `public`
 - **图库**：浏览、搜索、按存储/来源筛选、网格/列表切换、批量删除；统计概览与来源分布
 - **API 与 Twikoo**：全局 / 个人 Token；`POST /api/index.php` 兼容
diff --git a/docs-site/en/guide/configuration.md b/docs-site/en/guide/configuration.md
index 75ccbd9..a23c3b9 100644
--- a/docs-site/en/guide/configuration.md
+++ b/docs-site/en/guide/configuration.md
@@ -13,6 +13,7 @@ Configure PicHost via environment variables (Docker / `.env`) or the in-app **Se
 | Short image links | SQLite → env → default false | No |
 | Date-based paths | SQLite → env → default true | No |
 | Global auto-delete days | SQLite → env → default 0 | No |
+| Login verification | SQLite (Settings → Access control) | No |
 
 ## Variables
 
@@ -64,6 +65,18 @@ Delete images older than N days globally; `0` disables. Affects **new uploads af
 
 Local dev only: `true` bypasses login. Never use in production.
 
+### Login verification (Settings only)
+
+Configure under **Settings → Access control** (stored in SQLite; no env vars):
+
+| Method | Notes |
+| ------ | ----- |
+| **Local slider** (default) | No third-party service |
+| **Cloudflare Turnstile** | Site key + secret key |
+| **Cap** | API endpoint + secret |
+
+Login and registration share the same method. If misconfigured: `docker exec pichost slider` (or `npm run slider`) resets to the slider.
+
 ### Storage backends (optional)
 
 Admins usually add backends in **Storage** UI; env vars such as `STORAGE_BACKEND=s3` and `S3_*` are also supported. See [Storage](./storage.md).
@@ -99,5 +112,6 @@ Restart the container after changing env vars.
 | Date-based paths | `STORAGE_USE_DATE_PATH` / `STORAGE_LAYOUT` |
 | WebP quality | `WEBP_QUALITY` |
 | Auto-delete | `AUTO_DELETE_DAYS` |
+| Login verification | (Settings → Access control only) |
 
 Template: [`.env.example`](https://github.com/O96u/PicHost/blob/main/.env.example) in the repo root.
diff --git a/docs-site/en/guide/getting-started.md b/docs-site/en/guide/getting-started.md
index 0d3eb21..0748285 100644
--- a/docs-site/en/guide/getting-started.md
+++ b/docs-site/en/guide/getting-started.md
@@ -39,11 +39,23 @@ See `docker-compose.yml` in the repository.
 
 ## Sign in
 
-Management pages (upload, gallery, settings, etc.) require login. Enter username and password, **drag the slider to align with the gap**, then click **Sign in**.
+Management pages (upload, gallery, settings, etc.) require login. Enter username and password, complete the verification challenge, then click **Sign in**.
+
+The default is a **local slider** (align the thumb with the gap). Admins can switch to **Cloudflare Turnstile** or **Cap** under **Settings → Access control**, with the matching site key / secret or API endpoint.
 
 ![Login](/screenshots/login.png)
 
-If registration is enabled, create an account from the register page. Legacy deployments may still use a secret key (see the on-screen hint).
+If registration is enabled, create an account from the register page (same verification). Legacy deployments may still use a secret key (see the on-screen hint).
+
+### Locked out of verification
+
+If Turnstile / Cap is misconfigured and you cannot sign in, reset to the local slider on the server:
+
+```bash
+docker exec pichost slider
+```
+
+Local dev: `npm run slider`
 
 ## Forgot password
 
diff --git a/docs-site/en/guide/local-dev.md b/docs-site/en/guide/local-dev.md
index 1ea0dc4..10dd125 100644
--- a/docs-site/en/guide/local-dev.md
+++ b/docs-site/en/guide/local-dev.md
@@ -28,6 +28,7 @@ Open `http://localhost:3000/setup` to create the admin account. Data directory d
 | `npm run typecheck` | Type check |
 | `npm test` | Unit tests |
 | `npm run reset-password` | Reset password (optional username) |
+| `npm run slider` | Reset login verification to local slider |
 | `npm run migrate` | Preview legacy dir migration (`-- --apply` to run) |
 
 ## Dev-only variables
diff --git a/docs-site/en/guide/users-and-permissions.md b/docs-site/en/guide/users-and-permissions.md
index b2c7987..c154d0a 100644
--- a/docs-site/en/guide/users-and-permissions.md
+++ b/docs-site/en/guide/users-and-permissions.md
@@ -12,6 +12,7 @@ PicHost uses role-based access control (RBAC): **admin** and **user**. Enforceme
 | Storage management (`/storage`) | ✓ | — |
 | System settings (`/settings`) | ✓ | — |
 | Allow registration | ✓ | — |
+| Login verification (slider / Turnstile / Cap) | ✓ | — |
 | Global API token | ✓ | — |
 | Personal API token | ✓ | ✓ |
 | Gallery stats overview (incl. user count) | ✓ | partial |
@@ -34,7 +35,8 @@ Regular users see **API**, **Gallery** in the nav; user menu: **Change password*
 
 - By default only admins create users; **allow registration** is an admin setting
 - Passwords hashed with scrypt
-- Web login requires a slider captcha (align the thumb with the gap)
+- Web login/register requires verification: local slider by default; admins can switch to Turnstile or Cap under **Settings → Access control**
+- If verification is misconfigured: `docker exec pichost slider` resets to the local slider
 - Login rate limiting
 
 ## Upload preferences & auto-delete
diff --git a/docs-site/guide/configuration.md b/docs-site/guide/configuration.md
index aacc67b..5641e0b 100644
--- a/docs-site/guide/configuration.md
+++ b/docs-site/guide/configuration.md
@@ -11,6 +11,7 @@ PicHost 支持通过环境变量（Docker / `.env`）与后台 **设置** 页配
 | 简短图片链接 | SQLite → 环境变量 → 默认 false | 否 |
 | 按年/月分组存储 | SQLite → 环境变量 → 默认 true | 否 |
 | 全局自动删除天数 | SQLite → 环境变量 → 默认 0 | 否 |
+| 登录人机验证 | SQLite（设置 → 访问控制） | 否 |
 
 ## 变量说明
 
@@ -62,6 +63,18 @@ PicHost 支持通过环境变量（Docker / `.env`）与后台 **设置** 页配
 
 仅本地开发：`true` 绕过登录验证。生产环境勿用。
 
+### 登录人机验证（仅后台设置）
+
+在 **设置 → 访问控制** 配置，存入 SQLite，无对应环境变量：
+
+| 方式 | 说明 |
+| ---- | ---- |
+| **本地滑块**（默认） | 无需第三方服务 |
+| **Cloudflare Turnstile** | 填写 Site Key 与 Secret Key |
+| **Cap** | 填写 API Endpoint 与 Secret |
+
+登录与注册共用同一验证方式。若第三方配置错误导致无法登录，执行 `docker exec pichost slider`（或 `npm run slider`）恢复为本地滑块。
+
 ### 存储后端（可选）
 
 管理员通常在 **存储** 页添加后端；也可用环境变量引导（如 `STORAGE_BACKEND=s3` 与 `S3_*`）。详见 [存储](./storage.md)。
@@ -97,5 +110,6 @@ services:
 | 按年/月分组 | `STORAGE_USE_DATE_PATH` / `STORAGE_LAYOUT` |
 | WebP 质量 | `WEBP_QUALITY` |
 | 自动删除 | `AUTO_DELETE_DAYS` |
+| 登录验证 | （仅后台 **设置 → 访问控制**） |
 
 完整模板见仓库根目录 [`.env.example`](https://github.com/O96u/PicHost/blob/main/.env.example)。
diff --git a/docs-site/guide/getting-started.md b/docs-site/guide/getting-started.md
index e81f5a8..6eb1e9e 100644
--- a/docs-site/guide/getting-started.md
+++ b/docs-site/guide/getting-started.md
@@ -39,11 +39,23 @@ docker compose up -d
 
 ## 登录
 
-访问上传、图库、设置等管理页面前需登录。在登录卡片中填写用户名与密码，**拖动滑块对齐缺口**完成验证后点击 **登录**。
+访问上传、图库、设置等管理页面前需登录。在登录卡片中填写用户名与密码，完成人机验证后点击 **登录**。
+
+默认使用**本地滑块**（拖动滑块对齐缺口）。管理员可在 **设置 → 访问控制** 切换为 **Cloudflare Turnstile** 或 **Cap**，并填写对应 Site Key / Secret 或 API 端点。
 
 ![登录页](/screenshots/login.png)
 
-若管理员开启了开放注册，可前往注册页创建账号。遗留部署仍可能使用密钥登录（见界面提示）。
+若管理员开启了开放注册，可前往注册页创建账号（同样需完成人机验证）。遗留部署仍可能使用密钥登录（见界面提示）。
+
+### 验证方式被锁死时
+
+若 Turnstile / Cap 配置错误导致无法登录，可在服务器上重置为本地滑块：
+
+```bash
+docker exec pichost slider
+```
+
+本地开发：`npm run slider`
 
 ## 忘记密码
 
diff --git a/docs-site/guide/local-dev.md b/docs-site/guide/local-dev.md
index 21c37d6..937e56f 100644
--- a/docs-site/guide/local-dev.md
+++ b/docs-site/guide/local-dev.md
@@ -28,6 +28,7 @@ npm run dev
 | `npm run typecheck` | 类型检查 |
 | `npm test` | 单元测试 |
 | `npm run reset-password` | 重置密码（可选用户名） |
+| `npm run slider` | 将登录验证重置为本地滑块 |
 | `npm run migrate` | 预览遗留目录迁移（加 `-- --apply` 执行） |
 
 ## 开发专用环境变量
diff --git a/docs-site/guide/users-and-permissions.md b/docs-site/guide/users-and-permissions.md
index abe711f..520220c 100644
--- a/docs-site/guide/users-and-permissions.md
+++ b/docs-site/guide/users-and-permissions.md
@@ -12,6 +12,7 @@ PicHost 使用基于角色的访问控制（RBAC）：**管理员（admin）** 
 | 存储后端管理（`/storage`） | ✓ | — |
 | 系统设置（`/settings`） | ✓ | — |
 | 开放注册开关 | ✓ | — |
+| 登录人机验证方式（滑块 / Turnstile / Cap） | ✓ | — |
 | 全局 API Token 管理 | ✓ | — |
 | 个人 API Token | ✓ | ✓ |
 | 图库统计概览（含注册用户数） | ✓ | 部分 |
@@ -34,7 +35,8 @@ PicHost 使用基于角色的访问控制（RBAC）：**管理员（admin）** 
 
 - 默认仅管理员可创建用户；管理员可在设置中 **开放注册**
 - 密码使用 scrypt 哈希存储
-- Web 登录需先完成滑动拼图验证（拖动滑块对齐缺口）
+- Web 登录/注册需完成人机验证：默认本地滑块；管理员可在 **设置 → 访问控制** 切换 Turnstile 或 Cap
+- 验证配置错误无法登录时：`docker exec pichost slider` 重置为本地滑块
 - 登录失败有速率限制
 
 ## 上传偏好与自动删除