Update docs

README-zh.md

@@ -10,9 +10,7 @@
 
 另见：[WireGuard](https://github.com/hwdsl2/wireguard-install/blob/master/README-zh.md) 和 [IPsec VPN](https://github.com/hwdsl2/setup-ipsec-vpn/blob/master/README-zh.md) 服务器一键安装脚本。
 
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-#### [» :book: 限时免费电子书：Privacy Tools in the Age of AI](https://books2read.com/privacy?store=amazon)
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+**[» :book: Book: Privacy Tools in the Age of AI](https://books2read.com/privacy?store=amazon)  [搭建自己的 VPN 服务器分步指南](docs/vpn-book-zh.md)**
 
 ## 功能特性
 

README.md

@@ -10,9 +10,7 @@ This script will let you set up your own VPN server in just a few minutes, even
 
 See also: [WireGuard](https://github.com/hwdsl2/wireguard-install) and [IPsec VPN](https://github.com/hwdsl2/setup-ipsec-vpn) server auto setup scripts.
 
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-#### [» :book: FREE eBook (limited time): Privacy Tools in the Age of AI](https://books2read.com/privacy?store=amazon)
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+**[» :book: Book: Privacy Tools in the Age of AI](https://books2read.com/privacy?store=amazon)  [Build Your Own VPN Server](docs/vpn-book.md)**
 
 ## Features
 

docs/vpn-book-zh.md

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 [« 返回主页](../README-zh.md) | [English](vpn-book.md) | [中文](vpn-book-zh.md)
 
-## 限时免费电子书：Privacy Tools in the Age of AI
+## 新：Privacy Tools in the Age of AI
 
 了解如何在人工智能时代构建更高级别的隐私保护。[在 Amazon 上提供电子书](https://books2read.com/privacy?store=amazon)、平装本和有声读物格式。
 

docs/vpn-book.md

@@ -1,6 +1,6 @@
 [« Back to home page](../README.md) | [English](vpn-book.md) | [中文](vpn-book-zh.md)
 
-## FREE eBook (limited time): Privacy Tools in the Age of AI
+## New: Privacy Tools in the Age of AI
 
 Learn how to build your next-level privacy in the age of AI. [Available on Amazon](https://books2read.com/privacy?store=amazon) in eBook, paperback and audiobook formats.