fix dates

* 重要改动：提供了一个定义定理类环境的命令 \elegantnewtheorem；
* 重要改动：为所有内置定理类环境提供了带星号的版本，带星号的定理类环境不会编号；fix #167
* 将 TeX Gyre Termes 改为 TeX Gyre TermesX，使英文部分字形与 newtx
  系列宏包更相近；
* 重写了内置定理类环境的实现方法。

.gitignore

@@ -11,6 +11,7 @@
 *.cb
 *.cb2
 .*.lb
+.DS_Store
 clean.bat
 elegant*-cn.pdf
 elegant*-en.pdf

README.md

@@ -1,145 +1,37 @@
 <!-- Author : Dongsheng Deng & Liam Huang-->
 <!-- Program Email: elegantlatex2e@gmail.com -->
 
-[Homepage](https://elegantlatex.org/) | [Github](https://github.com/ElegantLaTeX/ElegantBook) | [CTAN](https://ctan.org/pkg/elegantbook) | [Download](https://github.com/ElegantLaTeX/ElegantBook/releases) | [Wiki](https://github.com/ElegantLaTeX/ElegantBook/wiki) | [Weibo](https://weibo.com/elegantlatex)
+[Homepage](https://elegantlatex.org/) | [Github](https://github.com/ElegantLaTeX/ElegantBook) | [CTAN](https://ctan.org/pkg/elegantbook) | [Download](https://github.com/ElegantLaTeX/ElegantBook/releases) | 
 
 ![License](https://img.shields.io/ctan/l/elegantbook.svg) ![CTAN Version](https://img.shields.io/ctan/v/elegantbook.svg) ![Github Version](https://img.shields.io/github/release/ElegantLaTeX/ElegantBook.svg) ![Repo Size](https://img.shields.io/github/repo-size/ElegantLaTeX/ElegantBook.svg)
 
----
-
-# ElegantBook 优美的 LaTeX 书籍模板
-
-ElegantBook 是为 LaTeX 书籍写作而设计的模板，由 [Dongsheng Deng](https://ddswhu.me/) 和 [Liam Huang](https://liam.page/) 创立，模板创立的初衷是方便我们自己做笔记 :smile:。如果你有其他问题、建议或者报告 bug，可以提交 issues 或者给我们发邮件：elegantlatex2e@gmail.com。QQ 用户交流群：692108391，欢迎加入。
-
-## 重要提示
-
-**版本提醒：** 由于新版本进行了重构，并且 3.06 版本对于封面进行了改版，3.06 以后的版本并不兼容之前版本，如果你想把之前版本的文件转为 3.06 以后的版本，请查看[跨版本转换](https://github.com/ElegantLaTeX/ElegantBook/wiki/convert)。我们强烈建议你使用最新版。
-
-**重要提示**：ElegantLaTeX 项目 **不接受** 任何非作者预约提交（pull requests）！
-
-## 致谢
-
-2019 年 5 月 20 日，ElegantBook 模板在 Github 上的 Star 数达到了 100，这对于 ElegantLaTeX 系列模板是一个非常重要的里程碑！在此特别感谢 ChinaTeX 以及 [LaTeX 工作室](http://www.latexstudio.net/)对于本系列模板的大力宣传与推广。LaTeX 工作室网站上有很多精彩的帖子和精致的模板，欢迎大家去挖掘里面的宝藏。这也是我所见到的国内最全面的 LaTeX 相关的网站。
-
-如果你喜欢我们的模板，你可以在 Github 上收藏我们的模板。
-
-## 捐赠
-
-如果您非常喜爱我们的模板或者我，你还可以选择捐赠以表达您对我们模板和我的支持。本模板自 3.08 版本发布了捐赠信息之后，收到了超过千元的捐赠（四舍五入就是一个亿），非常感谢！
-
-![](https://github.com/ElegantLaTeX/ElegantBook/wiki/donate.jpg)
-
-**赞赏费用的使用解释权归 ElegantLaTeX 所有，并且不接受监督，请自愿理性打赏**。10 元以上的赞赏，我们将列入捐赠榜，谢谢各位金主！（如果有遗漏，请务必联系我们，这对我们很重要）
-
-
-| 捐赠者   | 金额 |  时间  | 渠道 |
-| :------:   | :----:   | :----: | :------:   |
-| Lerh   | 10 RMB |   2019/05/15   | 微信 |
-| 越过地平线  | 10 RMB | 2019/05/15   | 微信 |
-| 银桑 | 20 RMB | 2019/05/27  | 微信 |
-| *空 | 10 RMB | 2019/05/30 | 微信 |
-| [latexstudio.net](http://www.latexstudio.net) | 666 RMB | 2019/06/05 | 支付宝 |
-| Cassis | 11 RMB | 2019/06/30 | 微信 |
-| *君 | 10 RMB | 2019/07/23 | 微信 |
-| P*u | 50 RMB | 2019/07/30 | 微信 |
-| *萌 | 19 RMB | 2019/08/28 | 微信 |
-| 曲豆豆 | 10 RMB | 2019/08/28 | 微信 |
-| 李博 | 100 RMB | 2019/10/06 | 微信 |
-| Njustsll | 10 RMB | 2019/10/11 | 微信 |
-| 刘志阔 | 99.99 RMB | 2019/10/15 | 支付宝 |
-| *涛 | 16 RMB | 2019/10/17 | 微信 |
-| 赤霓 | 12 RMB | 2019/10/17 | 支付宝 |
-| 追寻原风景 | 10 RMB | 2019/10/28 | 微信 |
-| 郭德良 | 88 RMB | 2019/11/03 | 微信 |
-| 自强不息 | 20 RMB | 2019/11/04 | 支付宝 |
-| 读书之虫 | 20 RMB | 2019/11/18 | 微信 |
-| *等    |  10 RMB | 2019/11/18 | 微信 |
-| *哲   |  20 RMB | 2019/11/18 | 微信 |
-| 佚名  | 10 RMB | 2019/11/24 | 微信 |
-| Jiye Qian | 66 RMB | 2019/12/04 | 微信 |
-| * 阳 | 20 RMB | 2019/12/05 | 微信 |
-| Catcher | 11 RMB | 2019/12/08 | 支付宝 |
-| 希尔波特门徒 | 10 RMB | 2019/12/09 | 支付宝 |
-| * 伟 | 10 RMB | 2019/12/09 | 微信 |
-| Simon | 20 RMB | 2019/12/11 | 支付宝 |
-| 流殇丶浅忆 | 66.60 RMB | 2019/12/18 | 支付宝 |
-| 羽 | 10 RMB | 2019/12/20 | 支付宝 |
-| * 琛 | 15 RMB | 2019/12/20 | 微信 |
-| 随风 | 20 RMB | 2019/12/27 | 支付宝 |
-| Ws  | 23.30 RMB | 2019/12/28 | 微信 |
-
-
-再次感谢大家对于模板的喜爱！
-
-## 协议
-
-本模板发布遵循 LaTeX 项目公共许可证 1.3 c 或更高版本。如果是衍生作品，请务必加入协议声明和模板信息（github、CTAN 地址）。
-
-## 衍生作
-
-+ [ElegantBookdown](https://github.com/XiangyunHuang/ElegantBookdown)：[XiangyunHuang](https://github.com/XiangyunHuang) 开发并维护的基于 ElegantBook 的 Bookdown 模板。
-+ [bookdownplus](https://github.com/pzhaonet/bookdownplus)：应网友要求，[pzhaonet](https://github.com/pzhaonet) 在 bookdownplus 收录了 ElegantPaper 模板，并为 Mac 做了字体适配。
-+ [PanBook](https://github.com/annProg/PanBook)：[annProg](https://github.com/annProg) 开发并维护的基于 Markdown 写作的工作流，收录了 ElegantBook 和 ElegantPaper 模板。
-
 -------
 
-# ElegantBook: An Elegant LaTeX Template for Books
+# ElegantBook: 优美的 LaTeX 书籍模板 An Elegant LaTeX Template for Books 
 
-ElegantBook is designed for writing books, created by [Dongsheng Deng](https://ddswhu.me/) and [Liam Huang](https://liam.page/). Just enjoy it! If you have any questions, suggestions or bug reports, you can create issues or contact us at elegantlatex2e@gmail.com.
+ElegantBook 是为 LaTeX 书籍写作而设计的模板，由 [Ethan Deng](https://github.com/EthanDeng) 和 [Liam Huang](https://github.com/Liam0205) 创立，现在主要由 [Ethan Deng](https://github.com/EthanDeng)、[乙醇](https://github.com/syvshc)和[死抠](https://github.com/sikouhjw)维护。如果你有其他问题、建议或者报告 bug，可以提交 issues 或者加入我们的 QQ 用户交流群：692108391。
 
-## Important Notes
-
-**Version Note**: Users for 2.x, please refer to [Version Convert](https://github.com/ElegantLaTeX/ElegantBook/wiki/convert). We strongly recommend that you use the latest version.
-
-**Important Info**: For some reasons, __unauthorial__ pull requests are **UNACCEPTABLE** since May 20, 2019. For those who want to help revise the templates, submit issues or clone to your own repository to modify under the LPPL-1.3c.
-
-## Acknowledgement
-
-_News_: _The number of stars on Github for ElegantBook reached 100 on May 20, 2019_.
-
-Thank ChinaTeX and [LaTeX Studio](http://www.latexstudio.net/) for their promotion. LaTeX studio offers tons of valuable posts and templates for discovery. It is the most comprehensive website on LaTeX in China. If you like our template, star on Github for supporting us.
-
-## Donation
-
-To express your love for our templates and/or our developers, please do not hesitate to tip us. Since last release of 3.08, we have received about a thousand RMB! (The emergence of a millionaire is on the way. Loading... )
-
-![](https://github.com/ElegantLaTeX/ElegantBook/wiki/donate.jpg)
-
-The explanation right of the tip usage belongs to ElegantLaTeX with no supervision. Feel free to tip us. Those who donate more than 10 RMB will be recorded in the Donation List. Thank all the tippers! Thank you all.
+ElegantBook is designed for writing books, created by [Ethan Deng](https://github.com/EthanDeng) and [Liam Huang](https://github.com/Liam0205), and maintained by [Ethan Deng](https://github.com/EthanDeng), [syvshc](https://github.com/syvshc) and [sikouhjw](https://github.com/sikouhjw). Just enjoy it! If you have any questions, suggestions or bug reports, you can create issues or contact us at elegantlatex2e@gmail.com.
 
 
-|      Tipper      | Amount     |   Date     | Channel |
-| :--------------: | :----:     | :-------:  | :-----: |
-| Lerh             | 10 RMB     | 2019/5/15  | Wechat  |
-| YueGuoDiPingXian | 10 RMB     | 2019/5/15  | Wechat  |
-| YinSang          | 20 RMB     | 2019/5/27  | Wechat  |
-| * Kong		       | 10 RMB     | 2019/05/30 | Wechat  |
-| [latexstudio.net](http://www.latexstudio.net) | 666 RMB | 2019/06/05 | Alipay |
-| Cassis    	     | 11 RMB     | 2019/06/30 | Wechat  |
-| * Jun		 	       | 10 RMB     | 2019/07/23 | Wechat  |
-| P*u              | 50 RMB     | 2019/07/30 | Wechat  |
-| * Meng 		       | 19 RMB     | 2019/08/28 | Wechat  |
-| QuDouDou 	       | 10 RMB     | 2019/08/28 | Wechat  |
-| LI Bo 			     | 100 RMB    | 2019/10/06 | Wechat  |
-| Njustsll 	       | 10 RMB     | 2019/10/11 | Wechat  |
-| LIU ZhiKuo 	     | 99.99 RMB  | 2019/10/15 | Alipay  |
-| * Tao            | 16 RMB     | 2019/10/17 | Wechat  |
-| ChiHong          | 12 RMB     | 2019/10/17 | Alipay  |
-| YuanFengJing     | 10 RMB     | 2019/10/28 | Wechat  |
-| GUO DeLiang      | 88 RMB     | 2019/11/03 | Wechat  |
-| ZiQiangBuXi      | 20 RMB     | 2019/11/03 | Alipay  |
-| DuShuZhiChong    | 20 RMB     | 2019/11/18 | Wechat  |
-| * Deng           | 10 RMB     | 2019/11/18 | Wechat  |
-| * Zhe            | 20 RMB     | 2019/11/18 | Wechat  |
+## 致谢 Acknowledgement
 
 
-## License
+特别感谢 [sikouhjw](https://github.com/sikouhjw) 和 [syvshc](https://github.com/syvshc) 长期以来对于 Github 上 issue 的快速回应，以及各个社区论坛对于 ElegantLaTeX 相关问题的回复。特别感谢 ChinaTeX 以及 [LaTeX 工作室](http://www.latexstudio.net/)对于本系列模板的大力宣传与推广。
+
+Thank [sikouhjw](https://github.com/sikouhjw) and [syvshc](https://github.com/syvshc) for their quick response to Github issues and continuously support work for ElegantLaTeX community. Thank ChinaTeX and [LaTeX Studio](http://www.latexstudio.net/) for their promotion. 
+
+
+## 协议 License
+
+本模板发布遵循 LaTeX 项目公共许可证 1.3 c 或更高版本。
+如果是衍生作品，请务必加入协议声明和模板信息（github、CTAN 地址）。
 
 This work is released under the LaTeX Project Public License, v1.3c or later.
 
 
-## Derivative Works
+## 衍生品 Derivative Works
 
-+ [ElegantBookdown](https://github.com/XiangyunHuang/ElegantBookdown)：[XiangyunHuang](https://github.com/XiangyunHuang) developed a Bookdown template based on ElegantBook.
-+ [bookdownplus](https://github.com/pzhaonet/bookdownplus): maintained by [pzhaonet](https://github.com/pzhaonet).
-+ [PanBook](https://github.com/annProg/PanBook)：a markdown-based writing workflow Developed by [annProg](https://github.com/annProg).
++ [ElegantBookdown](https://github.com/XiangyunHuang/ElegantBookdown)：[XiangyunHuang](https://github.com/XiangyunHuang) 开发并维护的基于 ElegantBook 的 Bookdown 模板。
++ [bookdownplus](https://github.com/pzhaonet/bookdownplus)：应网友要求，[pzhaonet](https://github.com/pzhaonet) 在 bookdownplus 收录了 ElegantPaper 模板，并为 Mac 做了字体适配。
++ [PanBook](https://github.com/annProg/PanBook)：[annProg](https://github.com/annProg) 开发并维护的基于 Markdown 写作的工作流，收录了 ElegantBook 和 ElegantPaper 模板。

elegantbook-en.tex

@@ -1,12 +1,12 @@
-\documentclass[lang=en,11pt]{elegantbook}
+\documentclass[11pt]{elegantbook}
 
 \title{An Elegant \LaTeX{} Template for Books}
 \subtitle{Classic Elegant\LaTeX{} Template}
 
 \author{Ethan Deng \& Liam Huang}
 \institute{Elegant\LaTeX{} Program}
-\date{February 10, 2020}
-\version{3.10}
+\date{Aug 15, 2022}
+\version{4.4}
 \bioinfo{Bio}{Information}
 
 \extrainfo{Victory won\rq t come to us unless we go to it. }
@@ -14,6 +14,13 @@
 \logo{logo-blue.png}
 \cover{cover.jpg}
 
+% modify the color in the middle of titlepage
+\definecolor{customcolor}{RGB}{32,178,170}
+\colorlet{coverlinecolor}{customcolor}
+\usepackage{cprotect}
+
+\addbibresource[location=local]{reference.bib} % bib
+
 \begin{document}
 
 \maketitle
@@ -22,69 +29,28 @@
 \tableofcontents
 
 \mainmatter
+
 \chapter{Elegant\LaTeX{} Templates}
 Elegant\LaTeX{} Program developers are intended to provide you beautiful, elegant, user-friendly templates. Currently, the Elegant\LaTeX{} is composed of \href{https://github.com/ElegantLaTeX/ElegantNote}{ElegantNote}, \href{https://github.com/ElegantLaTeX/ElegantBook}{ElegantBook}, \href{https://github.com/ElegantLaTeX/ElegantPaper}{ElegantPaper}, designed for typesetting notes, books, and working papers respectively. Latest releases are strongly recommended! This guide is aimed at briefly introducing the 101 of this template. For any other question, suggestion or comment, feel free to contact us on GitHub \href{https://github.com/ElegantLaTeX/ElegantBook/issues}{issues} or email us at \email{elegantlatex2e@gmail.com}.
 
 Contact Infos:
 \begin{itemize}
-  \item Homepage: \href{https://elegantlatex.org/}{https://elegantlatex.org/}
-  \item Github: \href{https://github.com/ElegantLaTeX/}{https://github.com/ElegantLaTeX/}
+  \item GitHub: \href{https://github.com/ElegantLaTeX/}{https://github.com/ElegantLaTeX/}
   \item CTAN: \href{https://ctan.org/pkg/elegantbook}{https://ctan.org/pkg/elegantbook}
-  \item Wiki: \href{https://github.com/ElegantLaTeX/ElegantBook/wiki}{https://github.com/ElegantLaTeX/ElegantBook/wiki}
   \item Download: \href{https://github.com/ElegantLaTeX/ElegantBook/releases}{release}, \href{https://github.com/ElegantLaTeX/ElegantBook/archive/master.zip}{latest version}
-  \item Weibo: Elegant\LaTeX{}
-  \item Wechat: Elegant\LaTeX{}
-  \item QQ: 692108391
-  \item Email: \email{elegantlatex2e@gmail.com}
 \end{itemize}
 
 
-\section{ElegantBook Updates}
-What\rq s new in this version:
-\begin{enumerate}
-  \item Introduce \lstinline{math} for math font, optional styles are \lstinline{newtx} and \lstinline{cm}.\\
-  \textbf{Notice}: The math font \lstinline{newtxmath} in previous versions is reset to default \LaTeX{} math font, to keep previous math font, please declare \lstinline{math=newtx}.
-  \item Introduce \lstinline{chinesefont} option, with \lstinline{founder}, \lstinline{ctexfont} and \lstinline{nofont} available.
-  \item Turn author information on the cover optional and add customized command \lstinline{\bioinfo}.
-  \item Add version history with command \lstinline{\datechange} and environment \lstinline{change}.
-  \item Add Chinese chapter style \lstinline{scheme} with option \lstinline{chinese}.
-  \item Since the bug raised by \lstinline{\lvert} is fixed, exchange package positions of \lstinline{ctex} and \lstinline{amsmath}.
-  \item Drop \lstinline{\lastpage} from header to avoid page anchor bug and adding \lstinline{\frontmatter}.
-  \item Revise bibliography option \lstinline{cite} with optional styles \lstinline{numbers},\lstinline{authoryear} and \lstinline{super}.
-  \item Introduce bibliography style option \lstinline{bibstyle}, with default bib style \lstinline{apalike} for English mode and \lstinline{gbt7714} package for Chinese mode.
-\end{enumerate}
+\section{Online Usage}
+You can visit \href{https://www.overleaf.com/}{Overleaf} to use our template online anywhere and anytime without local installation. To find our template, search \lstinline{elegantlatex} in the \lstinline{templates} or simply visit \href{https://www.overleaf.com/latex/templates?addsearch=elegantlatex}{search result}, choose the template you prefer and \lstinline{Open as Template} to own a copy yourself to edit freely. To learn more about Overleaf, please refer to \href{https://www.overleaf.com/learn}{Documentation}.
 
 
-\begin{note}
-  If you are using previous version, please delete \lstinline|\hypersetup{pageanchor=true}| and add \lstinline{\frontmatter} after \lstinline{\maketitle} and before \lstinline{\tableofcontents}. Users for 2.x, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/wiki/convert}{conversion}.
-\end{note}
+\section{Portable Version}
+For portable version, simply download lastest ElegantBook-master from GitHub or CTAN (to be more accurate, download \lstinline{elegantbook.cls}) and save the file(s) under your working directory. This way of installation is simple and convenient, but you have to manually update \lstinline{cls} now and then.
 
-\section{Installation and Update}
-Both portable version and installation package are available for this template, online usage is optional as well.
 
-\subsection{To Use Templates Online}
-Visit \href{https://www.overleaf.com/}{Overleaf} to use our template online anywhere and anytime without local installation. To find our template, search \lstinline{elegantlatex} in the \lstinline{templates} or simply visit \href{https://www.overleaf.com/latex/templates?addsearch=elegantlatex}{search result}, choose the template you prefer and \lstinline{Open as Template} to own a copy yourself to edit freely. To learn more about Overleaf, please refer to \href{https://www.overleaf.com/learn}{Documentation}.
-
-\begin{remark}
-  On Overleaf, please use \hologo{XeLaTeX} to compile articles in Chinese and \hologo{pdfLaTeX} to compile articles in English.
-\end{remark}
-
-\subsection{To Use Portable Version}
-For portable version, simply download lastest ElegantBook-master from Github or CTAN (to be more accurate, download \lstinline{elegantbook.cls}) and save the file(s) under your working directory. This way of installation is simple and convenient, but you have to manually update \lstinline{cls} now and then.
-
-\subsection{To Use Local Installation Version}
-If you are a \TeX{} Live 2019 user, using the \lstinline{tlshell}\footnote{namely, \TeX{} Live Manager} of \TeX{} Live 2019 direct installation package is strongly recommended. Simply search and open \lstinline{tlshell}, click on \lstinline{File -> Load Default Repository} or customize repository by \lstinline{Options}. Wait till the repository loads successfully, search \lstinline{elegantbook} by name, installation and update is just a click away.
-
-\begin{figure}[htbp]
-  \centering
-  \includegraphics[width=0.7\textwidth]{tlshell.png}
-  \caption{Use \TeX{} Live Shell to Install ElegantBook Template}
-\end{figure}
-
-\subsection{Update Templates}
-If you fail to update templates using \lstinline{tlshell}, please use cmd to update all the packages or switch to portable version instead.
-
-Use the following commands(administrator privileges) to update:
+\section{Update Templates}
+You can use cmd/terminal to update the tlmgr itself and all the packages, the commands are:
 \begin{lstlisting}
 tlmgr update --self
 tlmgr update --all
@@ -92,101 +58,35 @@ tlmgr update --all
 
 To learn more, please refer to \href{https://tex.stackexchange.com/questions/55437/how-do-i-update-my-tex-distribution}{How do I update my \TeX{} distribution?}
 
-\subsection{Other Release Versions}
-If you are a \TeX{} Live 2018 user and would like to update to \TeX{} Live 2019, the official solution is to uninstall 2018. If you want to save the bother of uninstallation and installation, please copy \lstinline{elegantbook.cls} to the installation directory of \TeX{} Live 2018 (default: \lstinline|C:\texlive\2018\texmf-dist\tex\latex\elegantbook| ), run \lstinline{texhash} in cmd.
-
-Excuse me? You are a  C\TeX{}  user? Sorry, this template is incompatible with C\TeX{}.
-
-For more details about the installation and usage of \TeX{} Live 2019, the compatibility of C\TeX{} and \TeX{} Live, please refer to OG (Official Guide) and/or \href{https://github.com/OsbertWang/install_latex/releases}{Install LaTeX v5.1} by OsbertWang.
-
-\section{User\rq s Selected Works Plan}
-Eight years have passed since the found of Elegant\LaTeX{} Program. It\rq s an honor that our templates are preferred by a lot of users. Hence, in order to promote more interactions among our users and know more about what you need, we are planning to provide a platform to display selected works of our users on Github or our homepage. If you want to show us your work(s), contact us via Email or other ways. Or if you have upload your work(s) on Github or Gitee etc., share the URL(s) with us. You can visit current available works \href{https://github.com/ElegantLaTeX/Archive/tree/master/Collections}{here}.
-
-\section{About Pull Request}
-For some reasons, pull requests will NOT by accepted since May 20, 2019. For those who want to help improve the templates, submit issues or clone to your own repository to modify under LPPL-1.3c.
-
-\section{Recruit Support Members}
-Recruit support members for Elegant\LaTeX{} to translate template OGs, maintain wiki entries using Markdown, update Wechat articles. No deadline for this recruitment.
-
-So far, Elegant\LaTeX{} has four Support Members:
-\begin{itemize}
-  \item OG Translator: \href{https://github.com/peggy2006xzyz}{YPY};
-  \item Wiki Maintainer: \href{https://github.com/izinngo}{Ingo Zinngo}, \href{https://github.com/xiaohao890809}{Xiaohao890809};
-  \item QQ Group Manager \& FAQ Maintainer: \href{https://github.com/sikouhjw}{Sikouhjw}.
-\end{itemize}
-
-BTW, thank \href{https://github.com/stone-zeng}{Xiangdong Zeng}, \href{https://github.com/latexers}{Zhuluren}, etc. for their help.
-
-\section{Acknowledgement}
-The number of stars on Github for ElegantBook reached 100 on May 20, 2019\footnote{372 stars by February 8, 2020!}.Thank China\TeX{} and \href{http://www.latexstudio.net/}{\LaTeX{} studio} for their promotion. \LaTeX{} studio offers tons of valuable posts and templates for discovery. It is the most comprehensive website on \LaTeX{} in China. 
-
-If you like our template, star on Github.
-
-\section{Donation}
-To express your love for our templates and/or our developers, please do not hesitate to tip us. Since last release of 3.08, we have received about 1,500 RMB! (The emergence of a millionaire is on the way. Loading... )
-\begin{figure}[!htb]
-  \centering
-  \includegraphics[width=0.45\textwidth]{donate.jpg}
-\end{figure}
-
-The explanation right of the tip usage belongs to Elegant\LaTeX{} with no supervision. Feel free to tip us. Those who donate more than 10 RMB will be recorded in the Donation List. Thank all the tippers!
-
-\begin{table}[!htb]
-  \centering
-  \caption{Donation List}
-  \begin{tabular}{*{4}{>{\scriptsize}c}|*{4}{>{\scriptsize}c}}
-    \toprule
-    \textbf{Tipper} & \textbf{Amount} & \textbf{Date} & \textbf{Channel} & \textbf{Tipper} & \textbf{Amount} & \textbf{Date} & \textbf{Channel} \\
-    \midrule
-    Lerh  & 10 RMB & 2019/05/15 & Wechat    & yueguodipingxian & 10 RMB & 2019/05/15 & Wechat \\
-    yinsang    & 20 RMB & 2019/05/27 & Wechat    & *kong    & 10 RMB & 2019/05/30 & Wechat \\
-    latexstudio.net & 666 RMB & 2019/06/05 & Alipay   & A*n   & 40 RMB & 2019/06/15 & Wechat \\
-    * xia   & 22 RMB & 2019/06/15 & Wechat    & * qian  & 21 RMB  & 2019/06/15 & Wechat \\
-    Cassis & 11 RMB & 2019/06/30 & Wechat    & * jun    & 10 RMB & 2019/07/23 & Wechat \\
-    P*u   & 50 RMB & 2019/07/30 & Wechat    & * meng    & 19 RMB & 2019/08/28 & Wechat \\
-    Qu Doudou   & 10 RMB & 2019/08/28 & Wechat    & Li Bo    & 100 RMB & 2019/10/06 & Wechat \\
-    Njustsll & 10 RMB & 2019/10/11 & Wechat    & Liu Zhikuo   & 99.99 RMB & 2019/10/15 & Alipay \\
-    * tao   & 16 RMB & 2019/10/17 & Wechat    & Chini    & 12 RMB & 2019/10/17 & Alipay \\
-    yuanfengjing & 10 RMB & 2019/10/28 & Wechat    & Guo Deliang   & 88 RMB & 2019/11/03 & Wechat \\
-    ziqiangbuxi  & 20 RMB & 2019/11/04 & Alipay   & dushuzhichong  & 20 RMB & 2019/11/18 & Wechat \\
-    * deng    & 10 RMB & 2019/11/18 & Wechat    & * zhe   & 20 RMB & 2019/11/18 & Wechat \\
-    anonymous    & 10 RMB & 2019/11/24 & Wechat    & Jiye Qian & 66 RMB & 2019/12/04 & Wechat \\
-    * yang   & 20 RMB & 2019/12/05 & Wechat    & Catcher & 11 RMB & 2019/12/08 & Alipay \\
-    xierbotementu & 10 RMB & 2019/12/09 & Alipay   & * wei   & 10 RMB & 2019/12/09 & Wechat \\
-    Simon & 20 RMB & 2019/12/11 & Alipay   & liushangqianyi & 66.60 RMB & 2019/12/18 & Alipay \\
-    yu     & 10 RMB & 2019/12/20 & Alipay   & *chen   & 15 RMB & 2019/12/20 & Wechat \\
-    suifeng   & 20 RMB & 2019/12/27 & Alipay   & Ws    & 23.30 RMB & 2019/12/28 & Wechat \\
-    chuba    & 100 RMB  & 2020/01/02 & Alipay   & p*e   & 20 RMB & 2020/01/03 & Wechat \\
-    Shunmx & 100 RMB & 2020/01/03 & Wechat    & hj    & 10 RMB & 2020/01/03 & Wechat \\
-    F*5   & 10 RMB & 2020/01/03 & Wechat    & S*m   & 20.20 RMB & 2020/01/03 & Wechat \\
-    erdaiqingzhi  & 13 RMB & 2020/01/14 & Alipay   & *?    & 66 RMB & 2020/01/15 & Wechat \\
-    Mr. Xiong & 20 RMB & 2020/01/17 & Wechat    & *bo    & 15 RMB & 2020/01/18 & Wechat \\
-    *zhe    & 10 RMB & 2020/02/02 & Wechat    &  Jackie &  88.80 RMB  &  2020/02/09 & Wechat \\
-    \bottomrule
-  \end{tabular}%
-  \label{tab:donation}%
-\end{table}%
-
-BTW, we provide Certificate of Donation for those who donated, tippers please leave your name(nickname) and email address for us to send the certificates.
-
-\begin{figure}[!htb]
-  \centering
-  \includegraphics[width=0.7\textwidth]{cert.pdf}
-\end{figure}
+\section{Other Release Versions}
+If you are a \TeX{} Live 2018/2019/2020/2021 user and would like to update, the official solution is to uninstall the previous version. If you want to save the bother of uninstallation and re-installation, please copy \lstinline{elegantbook.cls} to the installation directory of \TeX{} Live 2022 (default: \lstinline|C:\texlive\2022\texmf-dist\tex\latex\elegantbook| ), run \lstinline{texhash} in cmd.
 
 \chapter{ElegantBook Settings}
-
-This template is based on the Standard \LaTeX{} book class, so the options of book class work as well (Note that the option of papersize has no effect due to \lstinline{device} option). The default encoding is UTF-8 while \TeX{} Live is recommended. The test environment is Win10 + \TeX{} Live 2019, either \hologo{pdfLaTeX} or \lstinline{XeLaTeX} works fine. \lstinline{XeLaTeX} is preferred for Chinese articles.
+This template is based on the Standard \LaTeX{} book class, so the options of book class work as well (Note that the option of papersize has no effect due to \lstinline{device} option). The default encoding is UTF-8 while \TeX{} Live is recommended. The test environments are Win10/Ubuntu 20.04/macOS + \TeX{} Live 2022/ Mac\TeX{} 2022, either \hologo{pdfLaTeX} or \hologo{XeLaTeX} works fine for \lstinline{lang=en}.
 
 \section{Languages}
-We defined one option named \lstinline{lang} which has two alternative values, \lstinline{lang=en} (default) and \lstinline{lang=cn}. Different values will alter the captions of figure/table, abstract name, refname, etc. You can use this option as
+We defined one option named \lstinline{lang} which has two basic values, \lstinline{lang=en} (default) , \lstinline{lang=cn}. Different values will alter the captions of figure/table, abstract name, refname, etc. You can use this option as
+
 \begin{lstlisting}
 \documentclass[en]{elegantbook} 
 \documentclass[lang=en]{elegantbook}
 \end{lstlisting}
 
+Besides the two basic language translation, our user provide more options, here is a short brief introduction to these translation. Since I am not familiar with these languages, I can't guarantee that the translations are correct, please comment on GitHub if you have some questions.
+
+\begin{itemize}
+  \item Italian translation \lstinline{lang=it}, provided by \href{https://github.com/VincentMVV}{VincentMVV} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation};
+  \item French translation \lstinline{lang=fr}, provided by \href{https://github.com/abfek66}{abfek66} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation};
+  \item Dutch Translation \lstinline{lang=nl}, provided by \href{https://github.com/inktvis75}{inktvis75} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/108}{Dutch Translation};
+  \item Hungarian translation \lstinline{lang=hu}, provided by \href{https://github.com/palkotamas}{palkotamas}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/111}{Hungarian translation};
+  \item Deutsch translation \lstinline{lang=de}, provided by Lisa, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/113}{Deutsch translation};
+  \item Spanish translation \lstinline{lang=es}, provided by Gustavo A. Corradi, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/133}{Spanish translation};
+  \item Mongolian translation \lstinline{lang=mn}, provided by \href{https://github.com/Altantsooj}{Altantsooj}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/137}{Mongolian translation};
+  \item Japanese translation \lstinline{lang=jp}, provided by \href{https://github.com/inusturbo}{inusturbo}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/172}{Japanese translation}.
+\end{itemize}
+
 \begin{remark}
-Chinese Characters  are acceptable whenever \lstinline{lang=en} or \lstinline{lang=cn}. If you would like to include Chinese characters under (\lstinline{lstlisting}) environment, please use \hologo{XeLaTeX} to compile.
+Chinese Characters  are acceptable \textbf{ONLY} in \lstinline{lang=cn}.
 \end{remark}
 
 \section{Device Mode Option}
@@ -197,7 +97,7 @@ The option for device (\lstinline{device}) was originally used in ElegantNote, n
 \end{lstlisting}
 
 \section{Color Themes}
-This template contains 5 color themes, i.e. \textcolor{structure1}{\lstinline{green}}\footnote{Original default theme.}, \textcolor{structure2}{\lstinline{cyan}}, \textcolor{structure3}{\lstinline{blue}}(default), \textcolor{structure4}{\lstinline{gray}}, \textcolor{structure5}{\lstinline{black}}. You can choose \lstinline{green} with
+This template contains 5 color themes, i.e., \textcolor{structure1}{\lstinline{green}}\footnote{Original default theme.}, \textcolor{structure2}{\lstinline{cyan}}, \textcolor{structure3}{\lstinline{blue}}(default), \textcolor{structure4}{\lstinline{gray}}, \textcolor{structure5}{\lstinline{black}}. You can choose \lstinline{green} with
 \begin{lstlisting}
 \documentclass[green]{elegantbook} %or
 \documentclass[color=green]{elegantbook}
@@ -273,6 +173,12 @@ Besides, an extra command \lstinline{\bioinfo} is provided with two options--cap
 \bioinfo{Username}{115520}
 \end{lstlisting}
 
+You can change the color of the horizontal bar of the cover by
+\begin{lstlisting}
+  \definecolor{customcolor}{RGB}{32,178,170}
+  \colorlet{coverlinecolor}{customcolor}
+\end{lstlisting}
+
 \subsection{Cover Image}
 The cover image used in this template is from \href{https://pixabay.com/en/tea-time-poetry-coffee-reading-3240766/}{pixabay.com}. The image is completely free and can be used under any circumstance. The cover image size is $1280 \times 1024$. If you would like to change the cover, please crop it according to the size of the cover picture strictly. One free online image clipping site: \href{https://www.fotor.com/cn}{fotor.com}. Feel free to join our QQ Group to get more elegant covers.
 
@@ -302,45 +208,107 @@ We defined two sets of theorem modes, \lstinline{simple} style and \lstinline{fa
 In this template, we defined four different theorem class environments
 
 \begin{itemize}
-\item \textit{Theorem Environment}, including title and content, numbering corresponding to chapter. Three types depending on the format:
+\item \textit{Theorem Environments}, including title and content, numbering corresponding to chapter. Three types depending on the format:
    \begin{itemize}
       \item \textcolor{main}{\textbf{definition}} environment, the color is  \textcolor{main}{main};
-      \item \textcolor{second}{\textbf{theorem, lemma, corollary}} environment, the color is \textcolor{second} {second};
+      \item \textcolor{second}{\textbf{theorem, lemma, corollary, axiom, postulate}} environment, the color is \textcolor{second} {second};
       \item \textcolor{third}{\textbf{proposition}} environment, the color is \textcolor{third}{third}.
    \end{itemize}
-\item \textit{Example Environments}, including \textbf{example, exercise, problem} environment, auto numbering corresponding to chapter.
+\item \textit{Example Environment}, including \textbf{example, exercise, problem} environment, auto numbering according to chapter.
 \item \textit{Proof Environment}, including \textbf{proof, note} environment containing introductory symbol (\textbf{note} environment) or ending symbol (\textbf{proof} environment).
-\item \textit{Conclusion Environments}, including \textbf{conclusion, assumption, property, remark and solution}\footnote{We also define an option \lstinline{result}, which can hide the \lstinline{solution} and \lstinline{proof} environments. You can switch between \lstinline{result=answer} and \lstinline{result=noanswer}.} environments, all of which begin with boldfaced words, with format consistent with normal paragraphs.
+\item \textit{Conclusion Environment}, including \textbf{conclusion, assumption, property, remark and solution}\footnote{We also define an option \lstinline{result}, which can hide the \lstinline{solution} and \lstinline{proof} environments. You can switch between \lstinline{result=answer} and \lstinline{result=noanswer}.} environments, all of which begin with boldfaced words, with format consistent with normal paragraphs.
 \end{itemize}
 
-\subsection{Theorem Class Environments}
-Since the template uses the \lstinline{tcolorbox} package to customize the theorem class environments, it is slightly different from the normal theorem environments. The usage is as follows:
-\begin{lstlisting}
-\begin{theorem}{<theorem name>}{<label>}
-The content of theorem.
-\end{theorem}
-\end{lstlisting}
+All of theorem environments have star versions: \textcolor{main}{\textbf{definition*}}, \textcolor{second}{\textbf{theorem*}}, \textcolor{second}{\textbf{lemma*}}, \textcolor{second}{\textbf{corollary*}}, \textcolor{second}{\textbf{axiom*}}, \textcolor{second}{\textbf{postulate*}}, \textcolor{third}{\textbf{proposition*}}. Environments with an asterisk are not numbered.
 
-The first parameter \lstinline{<theorem name>} represents the name of the theorem, and the second parameter \lstinline{label} represents the label used in cross-reference with \verb|ref{thm:label}|. Note that cross-references must be prefixed with \lstinline{thm:}. 
+\subsection{Theorem Class Environments}
+
+\subsubsection{\lstinline{fancy} mode}
+
+In \lstinline{fancy} mode, the template uses the \lstinline{tcolorbox} package to customize the theorem class environments, it is slightly different from the normal theorem environments. The usage is as follows:
+\begin{lstlisting}
+  % name + label
+  \begin{theorem}{theorem name}{label}
+    The content of a theorem with name and label. 
+    Use \ref{thm:label} to refer this theorem.
+  \end{theorem}
+  % no name + label
+  \begin{theorem}{}{label no name}
+    The content of a theorem without name.
+    Use \ref{thm:label no name} to refer this theorem.
+  \end{theorem}
+  % name + no label
+  \begin{theorem}{theorem name}{}
+    The content of a theorem without label.
+    Can't refer this theorem.
+    The last {} can be removed.
+  \end{theorem}
+  % no name + no label
+  \begin{theorem}{}{}
+    The content of a theorem without name and label.
+    Can't refer this theorem.
+    Both of {} can be removed.
+  \end{theorem}
+  \end{lstlisting}
+
+The first parameter \lstinline{theorem name} represents the name of the theorem. If the current theorem has no name, please use \lstinline|{}|\cprotect\footnote{Unless this theorem has neither no label, you should not omit this \verb|{}|.}, and the second parameter \lstinline{label} represents the label used in cross-reference with \verb|\ref{thm:label}|. Note that cross-references must be prefixed with \lstinline{thm:}. 
 
 Other theorem class environments with the same usage includes:
 
 \begin{table}[htbp]
-   \centering
-   \caption{Theorem Class Environments}
-     \begin{tabular}{llll}
-     \toprule
-     Environment & Label text & Prefix & Cross-reference \\
-     \midrule
-     definition & label & def   & \lstinline|\ref{def:label}| \\
-     theorem & label & thm   & \lstinline|\ref{thm:label}| \\
-     lemma & label & lem   & \lstinline|\ref{lem:label}| \\
-     corrlary & label & cor   & \lstinline|\ref{cor:label}| \\
-     proposition & label & pro   & \lstinline|\ref{pro:label}| \\
-     \bottomrule
-     \end{tabular}%
-   \label{tab:theorem-class}%
- \end{table}%
+\centering
+\caption{Theorem Class Environments}
+  \begin{tabular}{llll}
+  \toprule
+  Environment & Label text & Prefix & Cross-reference \\
+  \midrule
+  definition & label & def   & \lstinline|\ref{def:label}| \\
+  theorem & label & thm   & \lstinline|\ref{thm:label}| \\
+  postulate & label & pos & \lstinline|\ref{pos:label}| \\
+  axiom & label & axi & \lstinline|\ref{axi:label}|\\
+  lemma & label & lem   & \lstinline|\ref{lem:label}| \\
+  corrlary & label & cor   & \lstinline|\ref{cor:label}| \\
+  proposition & label & pro   & \lstinline|\ref{pro:label}| \\
+  \bottomrule
+  \end{tabular}%
+\label{tab:theorem-class}%
+\end{table}%
+
+From version 4.1, you can write your theorem environments as follows:
+\begin{lstlisting}
+\begin{theorem}[theorem name]\label{thm:theorem-label}
+  The content of theorem.
+\end{theorem}
+% or
+\begin{theorem}\label{thm:theorem-without-name}
+  The content of theorem.
+\end{theorem}
+\end{lstlisting}
+
+In this case, cross-reference don't have to be prefixed, i.e. the parameter of \lstinline{\ref} is the same as that of \lstinline{\label}.
+ 
+\subsubsection{\lstinline{simple} mode}
+
+In \lstinline{simple} mode, the template uses the \lstinline{amsthm} package to customize the theorem class environments. The usage is as follows:
+
+\begin{lstlisting}
+\begin{theorem}[theorem name]\label{thm:theorem-label}
+  The content of theorem.
+\end{theorem}
+% or 
+\begin{theorem}\label{thm:theorem-without-name}
+  The content of theorem without name.
+\end{theorem}
+\end{lstlisting}
+
+\subsection{Counter for Theorem Environments}
+
+You can use \lstinline{thmcnt} option to control the theorem counter/number display style for the theorem environments, the acceptable options are \lstinline{chapter} (default) and \lstinline{section}:
+
+\begin{lstlisting}
+\documentclass[section]{elegantbook} % turn the Theorem 4.1 to Theorem 4.1.1 
+\documentclass[thmcnt=section]{elegantbook}
+\end{lstlisting}
 
 
 \subsection{Other Customized Environments}
@@ -365,13 +333,6 @@ These are all similar environments with slight differences lies in:
    \item Conclusion and other environments are normal paragraph environments with boldfaced introductory words.
 \end{itemize}
 
-\section{Base Hide Option}
-Hiding the end-of-chapter and end-of-page base is optional, simply type in:
-\begin{lstlisting}
-\documentclass[hide]{elegantbook} %or
-\documentclass[base=hide]{elegantbook}
-\end{lstlisting}
-
 
 \section{List Environments}
 This template uses \lstinline{tikz} to customize the list environments, with \lstinline{itemize} environment customized to the third depth and \lstinline{enumerate} environment customized to fourth depth. The effect is as follows\\[2ex]
@@ -404,27 +365,83 @@ This template uses \lstinline{tikz} to customize the list environments, with \ls
 \end{enumerate}
 \end{minipage}
 
+
+\section{Fonts}
+\textcolor{red}{\bfseries Alert} After v3.10, newtx is reset to cm, together with other two options, the \lstinline{math} font option offers:
+\begin{enumerate}
+  \item \lstinline{math=cm}(default), use \LaTeX{} default math font (recommended).
+  \item \lstinline{math=newtx}, use \lstinline{newtxmath} math font (may bring about bugs).
+  \item \lstinline{math=mtpro2}, use \lstinline{mtpro2} package to set math font.
+\end{enumerate}
+
+If you use \lstinline{newtx} fonts, type in:
+\begin{lstlisting}
+\documentclass[math=newtx]{elegantbook}
+\end{lstlisting}
+
+When you are using \lstinline{newtx}, please pay attention to the hyphens. For instance,
+\begin{equation}
+\int_{R^q} f(x,y) dy.\emph{of\kern0pt f} \sin x
+\end{equation}
+
+The corresponding code is: 
+\begin{lstlisting}
+\begin{equation}
+  \int_{R^q} f(x,y) dy.\emph{of \kern0pt f} \sin x
+\end{equation}
+\end{lstlisting}
+
+\subsection{Symbol Fonts}
+Feedback from some 3.08 users claims that error occurs when using our templates with  \lstinline{yhmath}, \lstinline{esvect} and other packages.
+\begin{lstlisting}
+LaTeX Error:
+Too many symbol fonts declared.
+\end{lstlisting}
+
+The reason is that the template redefines font for math so that no new math font is allowed to be added. To use \lstinline{yhmath} and/or \lstinline{esvect}, please locate \lstinline{yhmath} or \lstinline{esvect} in \lstinline{elegantbook.cls}, uncomment corresponding related code.
+
+\begin{lstlisting}
+%%% use yhmath pkg, uncomment following code
+% \let\oldwidering\widering
+% \let\widering\undefined
+% \RequirePackage{yhmath}
+% \let\widering\oldwidering
+
+%%% use esvect pkg, uncomment following code
+% \RequirePackage{esvect}
+\end{lstlisting}
+
 \section{Bibliography}
 
-This template uses \hologo{BibTeX} to generate the bibliography, the default bibliography style is \lstinline{aer}. Let's take a glance at the citation effect. ~\cite{en1} use data from a major peer-to-peer lending marketplace in China to study whether female and male investors evaluate loan performance differently. 
+This template uses biblatex to generate the bibliography, the default citestyle and bibliography style are both \lstinline{numeric}. Let's take a glance at the citation effect. ~\cite{en1} use data from a major peer-to-peer lending \cite{en3} marketplace in China to study whether female and male investors evaluate loan performance differently \parencite{en2}. 
 
-If you want to use \hologo{BibTeX}, you must create a file named \lstinline{reference.bib}, add bib items (from Google Scholar, Mendeley, EndNote, and etc.) to \lstinline{reference.bib} file, then cite the bibkey in the \lstinline{tex} file. The Bib\TeX{} will automatically generate the bibliography for the reference you cited. If you want to add some noncited reference to the bibliography, you can use 
-\begin{lstlisting}[frame=single]
-\nocite{EINAV2010,Havrylchyk2018} %or include some bibitems
-\nocite{*} %include all the bibitems
+If you want to use biblatex, you must create a file named \lstinline{reference.bib}, add bib items (from Google Scholar, Mendeley, EndNote, and etc.) to \lstinline{reference.bib} file, then cite the bibkey in the \lstinline{tex} file. The biber will automatically generate the bibliography for the reference you cited.
+
+In order to get the editors' auto-completion working, you need to add following code in your preamble:
+
+\begin{lstlisting}
+  \addbibresource[location=local]{reference.bib}
 \end{lstlisting}
 
-Three more options \lstinline{cite=numbers}, \lstinline{cite=super} and \lstinline{cite=authoryear} are available in this new version, with the default setting as \lstinline{numbers} since those major in science and technology use \lstinline{numbers} and/or \lstinline{cite=super} more often. For those who want to use \lstinline{cite=super} or \lstinline{authoryear}, please type in:
+Then include the print commands where you want to print the bibliography:
 \begin{lstlisting}
-\documentclass[cite=super]{elegantbook} % set cite for super style 
-\documentclass[super]{elegantbook}
-\documentclass[cite=authoryear]{elegantbook} % set cite for author-year style
-\documentclass[authoryear]{elegantbook}
+  \printbibliography[heading=bibintoc, title=\ebibname]
 \end{lstlisting}
 
-To change the bibliography style, this version introduces \lstinline{bibstyle} with default option apalike, for more options, refer to \href{https://www.overleaf.com/learn/latex/Bibtex_bibliography_styles}{\hologo{BibTeX} Bibliography Styles}. Type in
+
+
+
+To change the bibliography style, this version introduces two options: \lstinline{citestyle} and \lstinline{bibstyle}, please refer to \href{https://ctan.org/pkg/biblatex}{CTAN:biblatex} for more detail about these options. You can change your bibliography style as
+
 \begin{lstlisting}
-\documentclass[bibstyle=apalike]{elegantbook} 
+\documentclass[citestyle=numeric-comp, bibstyle=authoryear]{elegantbook} 
+\end{lstlisting}
+
+We also add the \lstinline{bibend} option to this template, you can choose \lstinline{biber} (default) or \lstinline{bibtex} as you like, \lstinline{biber} is recommended.
+
+\begin{lstlisting}
+\documentclass[bibtex]{elegantbook} % or
+\documentclass[bibend=bibtex]{elegantbook}
 \end{lstlisting}
 
 \section{Preface}
@@ -437,18 +454,13 @@ The content of introduction.
 \end{lstlisting}
 
 \section{Content Option and Depth}
-This version adds an option for content \lstinline{toc}, you can  choose either one column(\lstinline{onecol}) or two columns(\lstinline{twocol}). For two columns:
+Option for content \lstinline{toc}, you can  choose either one column(\lstinline{onecol}) or two columns(\lstinline{twocol}). For two columns:
 \begin{lstlisting}
 \documentclass[twocol]{elegantbook}
 \documentclass[toc=twocol]{elegantbook}
 \end{lstlisting}
 
-Default content depth is 1, use
-\begin{lstlisting}
-\setcounter{tocdepth}{2}
-\end{lstlisting}
-to make it 2.
-
+Default content depth is 1, use to use \lstinline|\setcounter{tocdepth}{2}|.
 
 \section{Introduction Environment}
 We create a introduction environment to display the structure of chapter. The basic useage is as follows:
@@ -477,7 +489,7 @@ You can change the title of this environment by modifying the optional argument
 \end{introduction}
 \end{lstlisting}
 
-\section{Problem Set}
+%\section{Problem Set}
 The environment \lstinline{problemset} is used at the end of each chapter to display corresponding exercises. Just type in the following sentences:
 \begin{lstlisting}
 \begin{problemset}
@@ -543,59 +555,6 @@ For tables and figures, note that floating environment is not allowed. You have
 
 \end{remark}
 
-\chapter{Fonts}
-Leave one chapter to introduce fonts to help users to solve font problems conveniently.
-
-\textcolor{red}{\bfseries Alert} After v3.10, newtx is reset to cm and \lstinline{chinesefont} option is added.
-
-\section{Math Fonts}
-This template defines a new command(\lstinline{math}), with three options:
-\begin{enumerate}
-  \item \lstinline{math=cm}(default), use \LaTeX{} default math font (recommended).
-  \item \lstinline{math=newtx}, use \lstinline{newtxmath} math font (may bring about bugs).
-  \item \lstinline{math=mtpro2}, use \lstinline{mtpro2} package to set math font.
-\end{enumerate}
-
-\section{Use newtx fonts}
-If you use \lstinline{newtx} fonts, type in:
-
-\begin{lstlisting}
-\documentclass[math=newtx]{elegantbook}
-\end{lstlisting}
-
-
-\subsection{Hyphens}
-Since the template uses \lstinline{newtx}, please pay attention to the hyphens. For instance,
-\begin{equation}
-\int_{R^q} f(x,y) dy.\emph{of\kern0pt f}
-\end{equation}
-
-The corresponding code is: 
-\begin{lstlisting}
-\begin{equation}
-\int_{R^q} f(x,y) dy.\emph{of \kern0pt f}
-\end{equation}
-\end{lstlisting}
-
-\section{Symbol Fonts}
-Feedback from some 3.08 users claims that error occurs when using our templates with  \lstinline{yhmath}, \lstinline{esvect} and other packages.
-\begin{lstlisting}
-LaTeX Error:
-Too many symbol fonts declared.
-\end{lstlisting}
-
-The reason is that the template redefines font for math so that no new math font is allowed to be added. To use \lstinline{yhmath} and/or \lstinline{esvect}, please locate \lstinline{yhmath} or \lstinline{esvect} in \lstinline{elegantbook.cls}, uncomment corresponding related code.
-
-\begin{lstlisting}
-%%% use yhmath pkg, uncomment following code
-% \let\oldwidering\widering
-% \let\widering\undefined
-% \RequirePackage{yhmath}
-% \let\widering\oldwidering
-
-%%% use esvect pkg, uncomment following code
-% \RequirePackage{esvect}
-\end{lstlisting}
 
 
 \chapter{ElegantBook Writing Sample}
@@ -617,8 +576,8 @@ The reason is that the template redefines font for math so that no new math font
 
 We will define the integral of a measurable function in three steps. First, we define the integral of a nonnegative simple function. Let $E$ be the measurable set in $\mathcal{R}^N$.
 
-\begin{definition}{Left Coset}{}
-Let $H$ be a subgroup of a group~$G$.  A \emph{left coset} of $H$ in $G$ is a subset of $G$ that is of the form $xH$, where $x \in G$ and $xH = \{ xh : h \in H \}$. Similarly a \emph{right coset} of $H$ in $G$ is a subset of $G$ that is of the form $Hx$, where $Hx = \{ hx : h \in H \}$ $\hbar$
+\begin{definition}[Left Coset]
+Let $H$ be a subgroup of a group~$G$.  A \emph{left coset} of $H$ in $G$ is a subset of $G$ that is of the form $xH$, where $x \in G$ and $xH = \{ xh : h \in H \}$. Similarly a \emph{right coset} of $H$ in $G$ is a subset of $G$ that is of the form $Hx$, where $Hx = \{ hx : h \in H \} \hbar$ 
 \end{definition}
 
 \begin{note}
@@ -627,24 +586,33 @@ Note that a subgroup~$H$ of a group $G$ is itself a left coset of $H$ in $G$.
 
 \lipsum[2]
 
-\begin{theorem}{Lagrange's Theorem}{}
-Let $G$ be a finite group, and let $H$ be a subgroup of $G$.  Then the order of $H$ divides the order of $G$.
+\begin{theorem}[Lagrange's Theorem] \label{thm:lg}
+Let $G$ be a finite group, and let $H$ be a subgroup of $G$. Then the order of $H$ divides the order of $G$.
 \end{theorem}
 
+As theorem \ref{thm:lg} refered.
+
 \lipsum[3]
 
 
-\begin{proposition}{Size of Left Coset}{}
+\begin{theorem}{theorem name}{label text}
+  The content of theorem.
+\end{theorem}
+
+we can refer this theorem as \ref{thm:label text}.
+
+
+\begin{proposition}[Size of Left Coset]
 Let $H$ be a finite subgroup of a group $G$.  Then each left coset of $H$ in $G$ has the same number of elements as $H$.
 \end{proposition}
 
 \begin{proof}
-Let $z$ be some element of $xH \cap yH$.  Then $z = xa$ for some $a \in H$, and $z = yb$ for some $b \in H$. If $h$ is any element of $H$ then $ah \in H$ and $a^{-1}h \in H$, since $H$ is a subgroup of $G$. But $zh = x(ah)$ and $xh = z(a^{-1}h)$ for all $h \in H$. Therefore $zH \subset xH$ and $xH \subset zH$, and thus $xH = zH$.  Similarly $yH = zH$, and thus $xH = yH$, as required.
+  Let $z$ be some element of $xH \cap yH$. Then $z = xa$ for some $a \in H$, and $z = yb$ for some $b \in H$. If $h$ is any element of $H$ then $ah \in H$ and $a^{-1}h \in H$, since $H$ is a subgroup of $G$. But $zh = x(ah)$ and $xh = z(a^{-1}h)$ for all $h \in H$. Therefore $zH \subset xH$ and $xH \subset zH$, and thus $xH = zH$.  Similarly $yH = zH$, and thus $xH = yH$, as required. 
 \end{proof}
 
 \begin{figure}[htbp]
   \centering
-  \includegraphics[width=0.6\textwidth]{scatter.pdf}
+  \includegraphics[width=0.6\textwidth]{scatter.jpg}
   \caption{Matplotlib: Scatter Plot Example\label{fig:scatter}}
 \end{figure}
 
@@ -652,6 +620,10 @@ Regression analysis is a powerful statistical method that allows you to examine
 
 Let's continue using our application training example. In this case, we'd want to measure the historical levels of satisfaction with the events from the past three years or so, as well as any information possible in regards to the independent variables. 
 
+\section{Second section}
+This second section\index{S!section} may include some special word, 
+and expand the ones already used\index{keywords!used}.
+
 
 \begin{table}[htbp]
   \small
@@ -687,9 +659,10 @@ Let's continue using our application training example. In this case, we'd want t
   \item Distributed storage and search.
 \end{itemize}
 
+%\problemset
 \begin{problemset}
   \item Solve the equation $5(- 3x - 2) - (x - 3) = -4(4x + 5) + 13$.
-  \item Find the distance between the points (-4 , -5) and (-1 , -1). 
+  \item Find the distance between the points $(-4 , -5)$ and $(-1 , -1)$.
   \item Find the slope of the line $5x - 5y = 7$.
 \end{problemset}
 
@@ -702,21 +675,79 @@ We list some FAQs for users to refer to:
   \item \question{I want to customize font and background color.}
   Please use \lstinline{pagecolor} to change background color, refer to \href{https://tex.stackexchange.com/questions/278544/xcolor-what-is-the-equivalent-of-default-text-color}{this} to customize font.
   \item \question{Which version should I choose?}
-  Please use \href{https://github.com/ElegantLaTeX/ElegantBook/releases}{Latest Release} via GitHub or \TeX{} Live 2019.
+  Please use \href{https://github.com/ElegantLaTeX/ElegantBook/releases}{Latest Release} via GitHub or \TeX{} Live 2022.
   \item \question{Which editor should I choose?}
-  You can use \TeX{} Live 2019 built-in \TeX works or \TeX Studio. You may refer to \href{https://github.com/EthanDeng/texworks-autocomplete}{\TeX{}works autocomplete}. \TeX{} Live 2019 + \TeX{}studio is strongly recommended. I myself use VS Code and Sublime Text. Related configurations can be found at \href{https://github.com/EthanDeng/vscode-latex}{vscode-latex} and \href{https://github.com/EthanDeng/sublime-text-latex}{sublime-text-latex}.
+  You can use \TeX{} Live 2022 built-in \TeX works or \TeX Studio. You may refer to \href{https://github.com/EthanDeng/texworks-autocomplete}{\TeX{}works autocomplete}. \TeX{} Live 2022 + \TeX{}studio is strongly recommended. Related configurations can be found at \href{https://github.com/EthanDeng/vscode-latex}{vscode-latex} and \href{https://github.com/EthanDeng/sublime-text-latex}{sublime-text-latex}.
   \item \question{Hello, we want to use ElegantBook to write a book about machine learning and would like your authorization.}
-  Feel free to use our templates by pointing out our copyright. For other issues, please refer to LPPL-1.3c. If you want to show us your work, share the URL with us afterwards.
+  Feel free to use our templates by pointing out our copyright. For other issues, please refer to LPPL-1.3c. If you want to show us your work, you can share the URL with us afterwards.
   \item \question{What is cross reference?}
   This template is aimed at who are not a complete beginner for \LaTeX{}. Please learn more about \LaTeX{} before using this template.
   \item \question{Is the language for code highlighting optional?}
   Yes, \lstinline{listings} package is used in ElegantBook, hence language is optional(e.g. \lstinline{language=Python}). For global setting, use \lstinline{lstset}. For more information, please refer to package documentations.
   \item \question{When will Beamer template (ElegantSlide or ElegantBeamer) forthcoming?}
-  Since there is an excellent theme \href{https://github.com/matze/mtheme}{Metropolis}, a Beta theme PreElegantSlide is available in QQ group. Feel free to download. A formal version is forthcoming in this year or next year.
+  Since there is an excellent theme \href{https://github.com/matze/mtheme}{Metropolis}, no plan for Beamer theme.
 \end{enumerate}
 
 \chapter{Version History}
-We revised our templates now and then. This section shows the version story of ElegantBook. We have nearly 100 submits and 16 releases on GitHub since uploaded.
+We revised our templates now and then. This section shows the version story of ElegantBook.
+
+
+\datechange{2022/08/15}{release of v4.4.}
+
+\begin{change}
+  \item Add custome theorem definition command \lstinline{\elegantnewtheorem};
+  \item Fix star environment(*) for inner environments (\href{https://github.com/ElegantLaTeX/ElegantBook/issues/167}{issue \#167});
+  \item Change English fonts from TeX Gyre Termes to TeX Gyre TermesX;
+  \item Re-construct some theorem environments to enchance compatibility;
+  \item Remove Gitee repo due the privacy policy;
+  \item Re-open Github pull requests.
+\end{change}
+
+
+
+
+\datechange{2022/04/09}{release of v4.3.}
+
+\begin{change}
+  \item Remove part newtx settings, set TeX Gyre Termes/Heros fonts under \hologo{XeLaTeX}.
+  \item Fix Chinese fonts in the theorem environments.
+  \item Add theorem counter option, \lstinline{thmcnt=section}.
+  \item Add bib option \lstinline{bibend}, which can take value of biber and bibtex.
+  \item \textbf{! Warnings}: The multilingual option may cause some unexpected errors, you can report in this \href{https://github.com/ElegantLaTeX/ElegantBook/issues/170}{issue}.
+\end{change}
+
+
+
+\datechange{2022/03/08}{release of v4.2.}
+
+\begin{change}
+  \item Bug fix due to the update of newtx fonts;
+  \item Add `Chapter' in TOC, and redefine \lstinline{\chaptername} to unify the logic under different languages;
+  \item Add language option for Japanese, \lstinline{lang=jp}.
+\end{change}
+
+
+\datechange{2021/05/02}{release of v4.1.}
+
+\begin{change}
+  \item \textbf{! Big Change}: Change the bibliography method from \hologo{BibTeX} to biblatex(with backend  \lstinline{biber});
+  \item \textbf{! Big Change}: Add support for the default theorem writing method (with optional name and label);
+  \item Add left and right space;
+  \item Support hyperlink from the text of TOC;
+  \item Remove the \hologo{pdfLaTeX} compatiblity check for Chinese.
+  \item Add multilingual support, for french \lstinline{lang=fr}, dutch \lstinline{lang=nl}, Hungarian  \lstinline{lang=hu}, Spanish \lstinline{lang=es}, Mongolian \lstinline{lang=mn} etc.
+\end{change}
+
+\datechange{2020/04/12}{release of v3.11, \textcolor{red}{\textbf{LAST} version of 3.x}.}
+
+
+\begin{change}
+  \item \textbf{! Fix}: Fix \lstinline{natbib option clash} problems caused by \lstinline{gbt7714} updates.
+  \item Remove \lstinline{base} decorations and its options since \lstinline{pgfornament} package is not included in \TeX{} Live 2020.
+  \item Fix spacing problem in some environments.
+  \item Introduce language option for Italian, \lstinline{lang=it}.
+\end{change}
+
 
 \datechange{2020/02/10}{release of v3.10}
 
@@ -744,10 +775,12 @@ We revised our templates now and then. This section shows the version story of E
 \end{change}
 
 
-\nocite{en1,en2,en3}
-\bibliography{reference}
+\nocite{en2,en3}
+
+\printbibliography[heading=bibintoc, title=\ebibname]
 \appendix
 
+
 \chapter{Mathematical Tools}
 
 This appendix covers some of the basic mathematics used in econometrics. We briefly discuss the properties of summation operators, study the properties of linear and some nonlinear equations, and review the ratios and percentages. We also introduce some special functions that are common in econometrics applications, including quadratic functions and natural logarithms. The first four sections require only basic algebraic techniques. The fifth section briefly reviews differential Calculus Although Calculus is not necessary to understand much of this book, it is used in some of the end-of-chapter appendices and in some of the more advanced topics in part 3.
@@ -760,4 +793,5 @@ This appendix covers some of the basic mathematics used in econometrics. We brie
 \sum_{i=1}^n x_i \equiv x_1 + x_2 +\cdots + x_n
 \end{equation}
 
+
 \end{document}

image/scatter.py

@@ -1,27 +0,0 @@
-# This file is the source file of the scatter.pdf
-# source page: https://matplotlib.org/gallery/shapes_and_collections/scatter.html
-import numpy as np
-import matplotlib.pyplot as plt
-
-# Fixing random state for reproducibility
-np.random.seed(19680801)
-
-
-N = 50
-x = np.random.rand(N)
-y = np.random.rand(N)
-colors = np.random.rand(N)
-area = (30 * np.random.rand(N))**2  # 0 to 15 point radii
-
-ax = plt.subplot(111)
-ax.scatter(x, y, s=area, c=colors, alpha=0.5)
-
-# Hide the right and top spines
-ax.spines['right'].set_visible(False)
-ax.spines['top'].set_visible(False)
-
-# Only show ticks on the left and bottom spines
-ax.yaxis.set_ticks_position('left')
-ax.xaxis.set_ticks_position('bottom')
-
-plt.savefig('scatter.pdf', transparent=True)