version 4.2

Add portuguese translation

.gitignore

@@ -0,0 +1,246 @@
+## Core latex/pdflatex auxiliary files:
+*.aux
+*.lof
+*.log
+*.lot
+*.fls
+*.out
+*.toc
+*.fmt
+*.fot
+*.cb
+*.cb2
+.*.lb
+clean.bat
+elegant*-cn.pdf
+elegant*-en.pdf
+*.dates
+
+## Intermediate documents:
+*.dvi
+*.xdv
+*-converted-to.*
+# these rules might exclude image files for figures etc.
+# *.ps
+# *.eps
+# *.pdf
+
+## Generated if empty string is given at "Please type another file name for output:"
+.pdf
+
+## Bibliography auxiliary files (bibtex/biblatex/biber):
+*.bbl
+*.bcf
+*.blg
+*-blx.aux
+*-blx.bib
+*.run.xml
+
+## Build tool auxiliary files:
+*.fdb_latexmk
+*.synctex
+*.synctex(busy)
+*.synctex.gz
+*.synctex.gz(busy)
+*.pdfsync
+
+## Auxiliary and intermediate files from other packages:
+# algorithms
+*.alg
+*.loa
+
+# achemso
+acs-*.bib
+
+# amsthm
+*.thm
+
+# beamer
+*.nav
+*.pre
+*.snm
+*.vrb
+
+# changes
+*.soc
+
+# cprotect
+*.cpt
+
+# elsarticle (documentclass of Elsevier journals)
+*.spl
+
+# endnotes
+*.ent
+
+# fixme
+*.lox
+
+# feynmf/feynmp
+*.mf
+*.mp
+*.t[1-9]
+*.t[1-9][0-9]
+*.tfm
+
+#(r)(e)ledmac/(r)(e)ledpar
+*.end
+*.?end
+*.[1-9]
+*.[1-9][0-9]
+*.[1-9][0-9][0-9]
+*.[1-9]R
+*.[1-9][0-9]R
+*.[1-9][0-9][0-9]R
+*.eledsec[1-9]
+*.eledsec[1-9]R
+*.eledsec[1-9][0-9]
+*.eledsec[1-9][0-9]R
+*.eledsec[1-9][0-9][0-9]
+*.eledsec[1-9][0-9][0-9]R
+
+# glossaries
+*.acn
+*.acr
+*.glg
+*.glo
+*.gls
+*.glsdefs
+
+# gnuplottex
+*-gnuplottex-*
+
+# gregoriotex
+*.gaux
+*.gtex
+
+# htlatex
+*.4ct
+*.4tc
+*.idv
+*.lg
+*.trc
+*.xref
+
+# hyperref
+*.brf
+
+# knitr
+*-concordance.tex
+# TODO Comment the next line if you want to keep your tikz graphics files
+*.tikz
+*-tikzDictionary
+
+# listings
+*.lol
+
+# makeidx
+*.idx
+*.ilg
+*.ind
+*.ist
+
+# minitoc
+*.maf
+*.mlf
+*.mlt
+*.mtc[0-9]*
+*.slf[0-9]*
+*.slt[0-9]*
+*.stc[0-9]*
+
+# minted
+_minted*
+*.pyg
+
+# morewrites
+*.mw
+
+# nomencl
+*.nlg
+*.nlo
+*.nls
+
+# pax
+*.pax
+
+# pdfpcnotes
+*.pdfpc
+
+# sagetex
+*.sagetex.sage
+*.sagetex.py
+*.sagetex.scmd
+
+# scrwfile
+*.wrt
+
+# sympy
+*.sout
+*.sympy
+sympy-plots-for-*.tex/
+
+# pdfcomment
+*.upa
+*.upb
+
+# pythontex
+*.pytxcode
+pythontex-files-*/
+
+# thmtools
+*.loe
+
+# TikZ & PGF
+*.dpth
+*.md5
+*.auxlock
+
+# todonotes
+*.tdo
+
+# easy-todo
+*.lod
+
+# xmpincl
+*.xmpi
+
+# xindy
+*.xdy
+
+# xypic precompiled matrices
+*.xyc
+
+# endfloat
+*.ttt
+*.fff
+
+# Latexian
+TSWLatexianTemp*
+
+## Editors:
+# WinEdt
+*.bak
+*.sav
+
+# Texpad
+.texpadtmp
+
+# Kile
+*.backup
+
+# KBibTeX
+*~[0-9]*
+
+# auto folder when using emacs and auctex
+./auto/*
+*.el
+
+# expex forward references with \gathertags
+*-tags.tex
+
+# standalone packages
+*.sta
+
+# generated if using elsarticle.cls
+*.spl

License

@@ -0,0 +1,416 @@
+The LaTeX Project Public License
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+
+LPPL Version 1.3c  2008-05-04
+
+Copyright 1999 2002-2008 LaTeX3 Project
+    Everyone is allowed to distribute verbatim copies of this
+    license document, but modification of it is not allowed.
+
+
+PREAMBLE
+========
+
+The LaTeX Project Public License (LPPL) is the primary license under
+which the LaTeX kernel and the base LaTeX packages are distributed.
+
+You may use this license for any work of which you hold the copyright
+and which you wish to distribute.  This license may be particularly
+suitable if your work is TeX-related (such as a LaTeX package), but 
+it is written in such a way that you can use it even if your work is 
+unrelated to TeX.
+
+The section `WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE',
+below, gives instructions, examples, and recommendations for authors
+who are considering distributing their works under this license.
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+We, the LaTeX3 Project, believe that the conditions below give you
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+12.  Nothing in this license is intended to, or may be used to, prevent
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+NO WARRANTY
+===========
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+MAINTENANCE OF THE WORK
+=======================
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+  b. If the search is unsuccessful or no action to resume active
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+ 3a. If the Current Maintainer is reachable and agrees to pass
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+     
+  b. If the Current Maintainer is not reachable and the Copyright
+     Holder agrees that maintenance of the Work be passed to you,
+     then this takes effect immediately upon announcement.  
+    
+ 4.  If you make an `intention announcement' as described in 2b. above
+     and after three months your intention is challenged neither by
+     the Current Maintainer nor by the Copyright Holder nor by other
+     people, then you may arrange for the Work to be changed so as
+     to name you as the (new) Current Maintainer.
+     
+ 5.  If the previously unreachable Current Maintainer becomes
+     reachable once more within three months of a change completed
+     under the terms of 3b) or 4), then that Current Maintainer must
+     become or remain the Current Maintainer upon request provided
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+
+A change in the Current Maintainer does not, of itself, alter the fact
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+in 2b) above.
+
+
+WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE
+======================================================
+
+This section contains important instructions, examples, and
+recommendations for authors who are considering distributing their
+works under this license.  These authors are addressed as `you' in
+this section.
+
+Choosing This License or Another License
+----------------------------------------
+
+If for any part of your work you want or need to use *distribution*
+conditions that differ significantly from those in this license, then
+do not refer to this license anywhere in your work but, instead,
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+A Recommendation on Modification Without Distribution
+-----------------------------------------------------
+
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+without altering any of its licensed components.
+
+How to Use This License
+-----------------------
+
+To use this license, place in each of the components of your work both
+an explicit copyright notice including your name and the year the work
+was authored and/or last substantially modified.  Include also a
+statement that the distribution and/or modification of that
+component is constrained by the conditions in this license.
+
+Here is an example of such a notice and statement:
+
+  %% pig.dtx
+  %% Copyright 2005 M. Y. Name
+  %
+  % This work may be distributed and/or modified under the
+  % conditions of the LaTeX Project Public License, either version 1.3
+  % of this license or (at your option) any later version.
+  % The latest version of this license is in
+  %   http://www.latex-project.org/lppl.txt
+  % and version 1.3 or later is part of all distributions of LaTeX
+  % version 2005/12/01 or later.
+  %
+  % This work has the LPPL maintenance status `maintained'.
+  % 
+  % The Current Maintainer of this work is M. Y. Name.
+  %
+  % This work consists of the files pig.dtx and pig.ins
+  % and the derived file pig.sty.
+
+Given such a notice and statement in a file, the conditions
+given in this license document would apply, with the `Work' referring
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+generated from `pig.dtx' using `pig.ins'), the `Base Interpreter'
+referring to any `LaTeX-Format', and both `Copyright Holder' and
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+the community even when you can no longer maintain and support it
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+
+Derived Works That Are Not Replacements
+---------------------------------------
+
+Several clauses of the LPPL specify means to provide reliability and
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+(compatible or incompatible) replacement of the original Work. If
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+completely different task), then clauses 6b and 6d shall not apply.
+
+
+Important Recommendations
+-------------------------
+
+ Defining What Constitutes the Work
+
+   The LPPL requires that distributions of the Work contain all the
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+   This could, for example, be achieved by explicitly listing all the
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+   using a line such as:
+
+    % This work consists of all files listed in manifest.txt.
+   
+   in that place.  In the absence of an unequivocal list it might be
+   impossible for the licensee to determine what is considered by you
+   to comprise the Work and, in such a case, the licensee would be
+   entitled to make reasonable conjectures as to which files comprise
+   the Work.
+

README-CN.md

@@ -0,0 +1,34 @@
+<!-- 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)
+
+![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
+
+**重要提示**：ElegantLaTeX 项目 **不接受** 任何非预授权的提交（pull requests）！
+
+## 致谢
+
+特别感谢 [sikouhjw](https://github.com/sikouhjw) 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。
+
+如果你喜欢我们的模板，你可以在 Github 上收藏我们的模板。
+
+## 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。

README.md

@@ -0,0 +1,34 @@
+<!-- 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)
+
+![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: 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.
+
+## Important Notes
+
+For some reasons, __unauthorized__ 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
+
+Thank [sikouhjw](https://github.com/sikouhjw) for his quick response to Github issues and continuously support work for ElegantLaTeX.
+
+Thank ChinaTeX and [LaTeX Studio](http://www.latexstudio.net/) for their promotion. 
+
+
+## License
+
+This work is released under the LaTeX Project Public License, v1.3c or later.
+
+
+## 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).

base.tex

@@ -1,34 +0,0 @@
-
-%% tikz setting
-\tikzset{x=1pt,y=1pt}
-\tikzset{elegant/.style={fill=main,draw=main},
-             null/.style={fill=white,draw=none}}
-             
-%% the triangle shape
-\newcommand{\triz}[2]{
-\begin{scope}[xshift=#1,rotate=#2]
-  \draw[elegant] (0,0) -- (105,6) .. controls (119,21) and (132,13) .. (135,12) .. controls (124,15) and (110,8) .. (107,-12) -- cycle;
-  \draw[null] (40,-0.5) -- (101,-4) -- (103,1)--cycle;
-\end{scope}
-}
-
-%% the ellipse shape +127
-\newcommand{\ellz}[1]{
-\begin{scope}[xshift=#1,yshift=3]
-\draw[elegant,rotate around={60:(0,-3)}](0,-3) ellipse (10.5 and 8.5);
-\draw[null](-3,-10) .. controls (-10,-6)  and (-2,6) .. (4.5,4) .. controls (0,3) and  (-4,-6) .. (-3,-10)--cycle;
-\end{scope}
-}
-
-%% the integration shape+147
-\newcommand{\intz}[1]{
-\begin{scope}[xshift=#1,yshift=2]
-\draw[elegant,draw=none,very thin] (-31,-14.5) .. controls (-17,-21)  and (-9,-8) .. (-3,0) .. controls (10,19) and (22,17) .. (29,9) .. controls (21,13) and (13,13) .. (3,-1) .. controls (-4,-11) and (-18,-27) .. (-31,-14.5) -- cycle ;
-\end{scope}
-}
-
-
-
-
-
-

elegantbook-cn.tex

@@ -0,0 +1,927 @@
+\documentclass[lang=cn,10pt]{elegantbook}
+
+\title{ElegantBook：优美的 \LaTeX{} 书籍模板}
+\subtitle{Elegant\LaTeX{} 经典之作}
+
+\author{Ethan Deng \& Liam Huang}
+\institute{Elegant\LaTeX{} Program}
+\date{March 8, 2022}
+\version{4.2}
+\bioinfo{自定义}{信息}
+
+\extrainfo{不要以为抹消过去，重新来过，即可发生什么改变。—— 比企谷八幡}
+
+\setcounter{tocdepth}{3}
+
+\logo{logo-blue.png}
+\cover{cover.jpg}
+
+% 本文档命令
+\usepackage{array}
+\newcommand{\ccr}[1]{\makecell{{\color{#1}\rule{1cm}{1cm}}}}
+
+% \definecolor{customcolor}{RGB}{32,178,170}
+% \colorlet{coverlinecolor}{customcolor}
+
+\begin{document}
+
+\maketitle
+\frontmatter
+
+\tableofcontents
+
+\mainmatter
+
+\chapter{Elegant\LaTeX{} 系列模板介绍}
+
+Elegant\LaTeX{} 项目组致力于打造一系列美观、优雅、简便的模板方便用户使用。目前由 \href{https://github.com/ElegantLaTeX/ElegantNote}{ElegantNote}，\href{https://github.com/ElegantLaTeX/ElegantBook}{ElegantBook}，\href{https://github.com/ElegantLaTeX/ElegantPaper}{ElegantPaper} 组成，分别用于排版笔记，书籍和工作论文。强烈推荐使用最新正式版本！本文将介绍本模板的一些设置内容以及基本使用方法。如果您有其他问题，建议或者意见，欢迎在 GitHub 上给我们提交 \href{https://github.com/ElegantLaTeX/ElegantBook/issues}{issues} 或者邮件联系我们。
+
+我们的联系方式如下，建议加入用户 QQ 群提问，这样能更快获得准确的反馈，加群时请备注 \LaTeX{} 或者 Elegant\LaTeX{} 相关内容。
+\begin{itemize}
+  \item 官网：\href{https://elegantlatex.org/}{https://elegantlatex.org/}
+  \item GitHub 网址：\href{https://github.com/ElegantLaTeX/}{https://github.com/ElegantLaTeX/}
+  \item CTAN 地址：\href{https://ctan.org/pkg/elegantbook}{https://ctan.org/pkg/elegantbook}
+  \item 下载地址：\href{https://github.com/ElegantLaTeX/ElegantBook/releases}{正式发行版}，\href{https://github.com/ElegantLaTeX/ElegantBook/archive/master.zip}{最新版}
+  \item 微博：Elegant\LaTeX{}
+  \item 微信公众号：Elegant\LaTeX{}
+  \item 用户 QQ 群：692108391 
+  \item 邮件：\email{elegantlatex2e@gmail.com}
+\end{itemize}
+
+
+\section{模板安装与更新}
+
+你可以通过免安装的方式使用本模板，包括在线使用和本地（文件夹内）使用两种方式，也可以通过 \TeX{} 发行版安装使用。
+
+\subsection{在线使用模板}
+
+我们把三套模板全部上传到 \href{https://www.overleaf.com/}{Overleaf} 上了，网络便利的用户可以直接通过 Overleaf 在线使用我们的模板。使用 Overleaf 的好处是无需安装 \TeX{} Live 2020，可以随时随地访问自己的文件。查找模板，请在 Overleaf 模板库里面搜索 \lstinline{elegantlatex} 即可，你也可以直接访问\href{https://www.overleaf.com/latex/templates?addsearch=elegantlatex}{搜索结果}。选择适当的模板之后，将其 \lstinline{Open as Template}，即可把模板存到自己账户下，然后可以自由编辑以及与别人一起协作。更多关于 Overleaf 的介绍和使用，请参考 Overleaf 的\href{https://www.overleaf.com/learn}{官方文档}。
+
+\begin{remark}
+Overleaf 上，中文需要使用 \hologo{XeLaTeX} 进行编译，英文建议使用 \hologo{pdfLaTeX} 编译。
+\end{remark}
+
+\subsection{本地免安装使用}
+
+\textbf{免安装}使用方法如下，从 GitHub 或者 CTAN 下载最新版，严格意义上只需要类文件 \lstinline{elegantbook.cls}。然后将模板文件放在你的工作目录下即可使用。这样使用的好处是，无需安装，简便；缺点是，当模板更新之后，你需要手动替换 \lstinline{cls} 文件。
+
+\subsection{发行版安装使用}
+
+本模板测试环境为 Win10 和 TeX Live 2021，如果你刚安装 \TeX{} Live 2021 用户，安装后建议升级全部宏包，升级方法：使用 cmd 运行 \lstinline{tlmgr update --all}，如果 tlmgr 需要更新，请使用 cmd 运行 \lstinline{tlmgr update --self}，如果更新过程中出现了中断，请改用 \lstinline{tlmgr update --self --all --reinstall-forcibly-removed} 更新。
+
+\subsection{更新问题}
+
+如果使用 \lstinline{tlshell} 无法更新模板，请使用命令行全部更新全部宏包或者使用免安装的方法使用本模板。
+
+通过命令行（管理员权限）输入下面的命令对 tlmgr 自身和全部宏包进行更新。
+
+\begin{lstlisting}
+  tlmgr update --self 
+  tlmgr update --all
+\end{lstlisting}
+
+更多的内容请参考 \href{https://tex.stackexchange.com/questions/55437/how-do-i-update-my-tex-distribution}{How do I update my \TeX{} distribution?}
+
+\subsection{其他发行版本}
+
+由于宏包版本问题，本模板不支持 C\TeX{} 套装，请务必安装 TeX Live。更多关于 \TeX{} Live 的安装使用以及 C\TeX{} 与 \TeX{} Live 的兼容、系统路径问题，请参考官方文档以及啸行的\href{https://github.com/OsbertWang/install-latex-guide-zh-cn/releases/}{一份简短的关于安装 \LaTeX{} 安装的介绍}。
+
+
+\section{关于提交}
+
+出于某些因素的考虑，Elegant\LaTeX{} 项目自 2019 年 5 月 20 日开始，\textbf{不再接受任何非作者预约性质的提交}（pull request)！如果你想改进模板，你可以给我们提交 issues，或者可以在遵循协议（LPPL-1.3c）的情况下，克隆到自己仓库下进行修改。
+
+
+\chapter{ElegantBook 设置说明}
+
+本模板基于基础的 book 文类，所以 book 的选项对于本模板也是有效的（纸张无效，因为模板有设备选项）。默认编码为 UTF-8，推荐使用 \TeX{} Live 编译。本文编写环境为 Win10 (64bit) + \TeX{} Live 2021，英文支持 \hologo{pdfLaTeX}，中文仅支持 \hologo{XeLaTeX} 编译。
+
+\section{语言模式}
+本模板内含两套基础语言环境 \lstinline{lang=cn}、\lstinline{lang=en}。改变语言环境会改变图表标题的引导词（图，表），文章结构词（比如目录，参考文献等），以及定理环境中的引导词（比如定理，引理等）。不同语言模式的启用如下：
+\begin{lstlisting}
+\documentclass[cn]{elegantbook} 
+\documentclass[lang=cn]{elegantbook}
+\end{lstlisting}
+
+除模板自带的两套语言设定之外，由网友提供的其他语言环境设置如下：
+\begin{itemize}
+  \item 由 \href{https://github.com/VincentMVV}{VincentMVV} 提供的意大利语翻译 \lstinline{lang=it}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation}；
+  \item 由 \href{https://github.com/abfek66}{abfek66} 提供的法语翻译 \lstinline{lang=fr}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation}；
+  % \item 由 \href{https://github.com/stultus}{stultus} 提供的马拉雅拉姆语翻译 \lstinline{lang=}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/90}{Malayalam translation}；
+  \item 由 \href{https://github.com/inktvis75}{inktvis75} 提供的荷兰语翻译 \lstinline{lang=nl}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/108}{Dutch Translation}；
+  \item 由 \href{https://github.com/palkotamas}{palkotamas} 提供的匈牙利语翻译 \lstinline{lang=hu}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/111}{Hungarian translation}；
+  \item 由 Lisa 提供的德语翻译 \lstinline{lang=de}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/113}{Deutsch translation}；
+  \item 由 Gustavo A. Corradi 提供的西班牙语的翻译 \lstinline{lang=es}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/133}{Spanish translation}；
+  \item 由 \href{https://github.com/Altantsooj}{Altantsooj} 提供的蒙古语的翻译 \lstinline{lang=mn}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/137}{Mongolian translation}；
+  \item 由 \href{https://github.com/inusturbo}{inusturbo} 提供的日本语的翻译 \lstinline{lang=jp}，相关讨论见 \href{https://github.com/ElegantLaTeX/ElegantBook/issues/172}{Japanese Translation}。
+\end{itemize}
+
+
+
+\begin{remark}
+以上各个语言的设定均为网友设定，我们未对上述翻译进行过校对，如果有问题，请在对应的 issue 下评论。并且，只有中文环境（\lstinline{lang=cn}）才可以输入中文。
+\end{remark}
+
+\section{设备选项}
+最早我们在 ElegantNote 模板中加入了设备选项（\lstinline{device}），后来，我们觉得这个设备选项的设置可以应用到 ElegantBook 中\footnote{不过因为 ElegantBook 模板封面图片的存在，在修改页面设计时，需要对图片进行裁剪。}，而且 Book 一般内容比较多，如果在 iPad 上看无需切边，放大，那用户的阅读体验将会得到巨大提升。你可以使用下面的选项将版面设置为 iPad 设备模式\footnote{默认为 normal 模式，也即 A4 纸张大小。}
+\begin{lstlisting}
+\documentclass[pad]{elegantbook} %or
+\documentclass[device=pad]{elegantbook}
+\end{lstlisting}
+
+\section{颜色主题}
+
+本模板内置 5 组颜色主题，分别为 \textcolor{structure1}{\lstinline{green}}\footnote{为原先默认主题。}、\textcolor{structure2}{\lstinline{cyan}}、\textcolor{structure3}{\lstinline{blue}}（默认）、\textcolor{structure4}{\lstinline{gray}}、\textcolor{structure5}{\lstinline{black}}。另外还有一个自定义的选项  \lstinline{nocolor}。调用颜色主题 \lstinline{green} 的方法为 
+\begin{lstlisting}
+\documentclass[green]{elegantbook} %or
+\documentclass[color=green]{elegantbook}
+\end{lstlisting}
+
+\begin{table}[htbp]
+  \caption{ElegantBook 模板中的颜色主题\label{tab:color thm}}
+  \centering
+  \begin{tabular}{ccccccc}
+  \toprule
+    & \textcolor{structure1}{green} 
+    & \textcolor{structure2}{cyan} 
+    & \textcolor{structure3}{blue}
+    & \textcolor{structure4}{gray} 
+    & \textcolor{structure5}{black} 
+    & 主要使用的环境\\
+  \midrule
+    structure & \ccr{structure1}
+    & \ccr{structure2}
+    & \ccr{structure3} 
+    & \ccr{structure4} 
+    & \ccr{structure5} 
+    & chapter \ section \ subsection \\
+    main      & \ccr{main1}
+    & \ccr{main2}
+    & \ccr{main3}
+    & \ccr{main4}
+    & \ccr{main5}
+    & definition \ exercise \ problem \\
+    second    & \ccr{second1}
+    & \ccr{second2}
+    & \ccr{second3}
+    & \ccr{second4}
+    & \ccr{second5}
+    & theorem \ lemma \ corollary\\
+    third     & \ccr{third1}
+    & \ccr{third2}
+    & \ccr{third3}
+    & \ccr{third4}
+    & \ccr{third5}
+    & proposition\\
+  \bottomrule
+  \end{tabular}
+\end{table}
+
+如果需要自定义颜色的话请选择 \lstinline{nocolor} 选项或者使用 \lstinline{color=none}，然后在导言区定义 structurecolor、main、second、third 颜色，具体方法如下：
+\begin{lstlisting}[tabsize=4]]
+\definecolor{structurecolor}{RGB}{0,0,0}
+\definecolor{main}{RGB}{70,70,70}    
+\definecolor{second}{RGB}{115,45,2}    
+\definecolor{third}{RGB}{0,80,80}
+\end{lstlisting}
+
+\section{封面}
+
+\subsection{封面个性化}
+
+从 3.10 版本开始，封面更加弹性化，用户可以自行选择输出的内容，包括 \lstinline{\title} 在内的所有封面元素都可为空。目前封面的元素有
+
+\begin{table}[htbp]
+  \centering
+  \caption{封面元素信息}
+  \begin{tabular}{p{0.07\textwidth}p{0.15\textwidth}|p{0.07\textwidth}p{0.15\textwidth}|p{0.07\textwidth}p{0.15\textwidth}}
+    \toprule
+    信息 & 命令 & 信息 & 命令 & 信息 & 命令 \\
+    \midrule
+    标题 & \lstinline|\title| & 副标题 & \lstinline|\subtitle| & 作者 & \lstinline|\author| \\
+    机构 & \lstinline|\institute| & 日期 &  \lstinline|\date| & 版本 & \lstinline|\version| \\
+    箴言 & \lstinline|\extrainfo| & 封面图 & \lstinline|\cover| & 徽标 & \lstinline|\logo| \\
+    \bottomrule
+  \end{tabular}
+\end{table}
+
+另外，额外增加一个 \lstinline{\bioinfo} 命令，有两个选项，分别是信息标题以及信息内容。比如需要显示{\kaishu User Name：111520}，则可以使用 
+\begin{lstlisting}
+\bioinfo{User Name}{115520}
+\end{lstlisting}
+
+封面中间位置的色块的颜色可以使用下面命令进行修改：
+\begin{lstlisting}
+  \definecolor{customcolor}{RGB}{32,178,170}
+  \colorlet{coverlinecolor}{customcolor}
+\end{lstlisting}
+
+\subsection{封面图}
+
+本模板使用的封面图片来源于 \href{https://pixabay.com/en/tea-time-poetry-coffee-reading-3240766/}{pixabay.com}\footnote{感谢 China\TeX{} 提供免费图源网站，另外还推荐 \href{https://www.pexels.com/}{pexels.com}。}，图片完全免费，可用于任何场景。封面图片的尺寸为 $1280 \times 1024$, 更换图片的时候请\textbf{严格}按照封面图片尺寸进行裁剪。推荐一个免费的在线图片裁剪网站 \href{https://www.fotor.com/cn}{fotor.com}。用户 QQ 群内有一些合适尺寸的封面，欢迎取用。
+
+\subsection{徽标}
+
+本文用到的 Logo 比例为 1:1，也即正方形图片，在更换图片的时候请选择合适的图片进行替换。
+
+\subsection{自定义封面}
+
+另外，如果使用自定义的封面，比如 Adobe illustrator 或者其他软件制作的 A4 PDF 文档，请把 \lstinline{\maketitle} 注释掉，然后借助 \lstinline{pdfpages} 宏包将自制封面插入即可。如果使用 \lstinline{titlepage} 环境，也是类似。如果需要 2.x 版本的封面，请参考 \href{https://github.com/EthanDeng/etitlepage}{etitlepage}。
+
+\section{章标标题}
+
+本模板内置 2 套\textit{章标题显示风格}，包含 \lstinline{hang}（默认）与 \lstinline{display} 两种风格，区别在于章标题单行显示（\lstinline{hang}）与双行显示（\lstinline{display}），本说明使用了 \lstinline{hang}。调用方式为
+\begin{lstlisting}
+\documentclass[hang]{elegantbook} %or
+\documentclass[titlestyle=hang]{elegantbook}
+\end{lstlisting}
+
+在章标题内，章节编号默认是以数字显示，也即{\kaishu 第 1 章}，{\kaishu 第 2 章}等等，如果想要把数字改为中文，可以使用
+\begin{lstlisting}
+\documentclass[chinese]{elegantbook} %or
+\documentclass[scheme=chinese]{elegantbook}
+\end{lstlisting}
+
+\section{数学环境简介}
+
+在我们这个模板中，我们定义了两种不同的定理模式 \lstinline{mode}，包括简单模式（\lstinline{simple}）和炫彩模式（\lstinline{fancy}），默认为 \lstinline{fancy} 模式，不同模式的选择为
+\begin{lstlisting}
+\documentclass[simple]{elegantbook} %or
+\documentclass[mode=simple]{elegantbook}
+\end{lstlisting}
+
+本模板定义了四大类环境
+
+\begin{itemize}
+  \item \textit{定理类环境}，包含标题和内容两部分，全部定理类环境的编号均以章节编号。根据格式的不同分为 3 种
+    \begin{itemize}
+      \item \textcolor{main}{\textbf{definition}} 环境，颜色为 \textcolor{main}{main}；
+      \item \textcolor{second}{\textbf{theorem、lemma、corollary}} 环境，颜色为 \textcolor{second} {second}；
+      \item \textcolor{third}{\textbf{proposition}} 环境，颜色为 \textcolor{third}{third}。
+    \end{itemize}
+  \item \textit{示例类环境}，有 \textbf{example、problem、exercise} 环境（对应于例、例题、练习），自动编号，编号以章节为单位，其中 \textbf{exercise} 有提示符。
+  \item \textit{提示类环境}，有 \textbf{note} 环境，特点是：无编号，有引导符。
+  \item \textit{结论类环境}，有 \textbf{conclusion、assumption、property、remark、solution} 环境\footnote{本模板还添加了一个 result 选项，用于隐藏 \lstinline{solution} 和 \lstinline{proof} 环境，默认为显示（\lstinline{result=answer}），隐藏使用 \lstinline{result=noanswer}。}，三者均以粗体的引导词为开头，和普通段落格式一致。
+\end{itemize}
+
+\subsection{定理类环境的使用}
+
+由于本模板使用了 \lstinline{tcolorbox} 宏包来定制定理类环境，所以和普通的定理环境的使用有些许区别，定理的使用方法如下：
+\begin{lstlisting}
+\begin{theorem}{theorem name}{label}
+  The content of theorem.
+\end{theorem}
+\end{lstlisting}
+
+第一个必选项 \lstinline{theorem name} 是定理的名字，第二个必选项 \lstinline{label} 是交叉引用时所用到的标签，交叉引用的方法为 \verb|\ref{thm:label}|。请注意，交叉引用时必须加上前缀 \lstinline{thm:}。
+
+在用户多次反馈下，4.x 之后，引入了原生定理的支持方式，也就是使用可选项方式：
+
+\begin{lstlisting}
+\begin{theorem}[theorem name] \label{thm:theorem-label}
+  The content of theorem.
+\end{theorem}
+% or 
+\begin{theorem} \label{thm:theorem-withou-name}
+  The content of theorem without name.
+\end{theorem}
+\end{lstlisting}
+
+其他相同用法的定理类环境有：
+
+\begin{table}[htbp]
+   \centering
+   \caption{定理类环境}
+     \begin{tabular}{llll}
+     \toprule
+     环境名 & 标签名 & 前缀 & 交叉引用 \\
+     \midrule
+     definition & label & def   & \lstinline|\ref{def:label}| \\
+     theorem & label & thm   & \lstinline|\ref{thm:label}| \\
+     lemma & label & lem   & \lstinline|\ref{lem:label}| \\
+     corollary & label & cor   & \lstinline|\ref{cor:label}| \\
+     proposition & label & pro   & \lstinline|\ref{pro:label}| \\
+     \bottomrule
+     \end{tabular}%
+   \label{tab:theorem-class}%
+ \end{table}%
+ 
+% \subsection{算法环境}
+
+ 
+% \begin{algorithm}\label{alg:test}
+%   \Input{A bitmap $I$ of size $w \times l$}
+%   \Output{A partition of the bitmap}
+%   \BlankLine
+%   \emph{special treatment of the first line}\;
+%   \For{$i \leftarrow 2$ \KwTo $l$}{
+%     \emph{special treatment of the first element of line $i$}\;
+%     \For{$j \leftarrow 2$ \KwTo $w$}{\label{forins}
+%       $\Left \leftarrow \FindCompress{$I[i,j-1]$}$\;
+%       $\Up \leftarrow \FindCompress{$I[i-1,]$}$\;
+%       $\This \leftarrow \FindCompress{$I[i,j]$}$\;
+%       \If(\tcp*[h]{O(\Left,\This)==1}){\Left compatible with \This}{\label{lt}
+%         \lIf{$\Left < \This$}{$\Union{\Left,\This}$}
+%         \lElse{$\Union{\This,\Left}$}
+%       }
+%       \If(\tcp*[f]{O(\Up,\This)==1}){\Up compatible with \This}{\label{ut}
+%         \lIf{$\Up < \This$}{$\Union{\Up,\This}$}
+%         \tcp{\This is put under \Up to keep tree as flat as possible}\label{cmt}
+%         \lElse{$\Union{\This,\Up}$}\tcp*[r]{\This{} linked to \Up}\label{lelse}
+%       }
+%     }
+%     \lForEach{element $e$ of the line $i$}{\FindCompress{p}}
+%   }
+%   \caption{disjoint decomposition}\label{algo_disjdecomp}
+% \end{algorithm}
+
+\subsection{其他环境的使用}
+
+其他三种环境没有选项，可以直接使用，比如 \lstinline{example} 环境的使用方法与效果：
+\begin{lstlisting}
+\begin{example}
+   This is the content of example environment.
+\end{example}
+\end{lstlisting}
+
+这几个都是同一类环境，区别在于
+
+\begin{itemize}
+  \item 示例环境（example）、练习（exercise）与例题（problem）章节自动编号；
+  \item 注意（note），练习（exercise）环境有提醒引导符；
+  \item 结论（conclusion）等环境都是普通段落环境，引导词加粗。
+\end{itemize}
+
+\section{列表环境}
+本模板借助于 \lstinline{tikz} 定制了 \lstinline{itemize} 和 \lstinline{enumerate} 环境，其中 \lstinline{itemize} 环境修改了 3 层嵌套，而 \lstinline{enumerate} 环境修改了 4 层嵌套（仅改变颜色）。示例如下\\[2ex]
+\begin{minipage}[b]{0.49\textwidth}
+  \begin{itemize}
+    \item first item of nesti;
+    \item second item of nesti;
+      \begin{itemize}
+        \item first item of nestii;
+        \item second item of nestii;
+        \begin{itemize}
+          \item first item of nestiii;
+          \item second item of nestiii.
+        \end{itemize}   
+      \end{itemize}
+  \end{itemize}
+\end{minipage}
+\begin{minipage}[b]{0.49\textwidth}
+  \begin{enumerate}
+    \item first item of nesti;
+    \item second item of nesti;
+      \begin{enumerate}
+        \item first item of nestii;
+        \item second item of nestii;
+        \begin{enumerate}
+          \item first item of nestiii;
+          \item second item of nestiii.
+        \end{enumerate}   
+      \end{enumerate}
+  \end{enumerate}
+\end{minipage}
+
+\section{参考文献}
+
+此模板使用了 \hologo{biber} 来生成参考文献，也即使用 \lstinline{biblatex} 宏包，在中文示例中，使用了 \lstinline{gbt7714} 宏包。参考文献示例：\cite{cn1,en2,en3} 使用了中国一个大型的 P2P 平台（人人贷）的数据来检验男性投资者和女性投资者在投资表现上是否有显著差异。
+
+你可以在谷歌学术，Mendeley，Endnote 中获得文献条目（bib item），然后把它们添加到 \lstinline{reference.bib} 中。在文中引用的时候，引用它们的键值（bib key）即可。注意需要在编译的过程中添加 \hologo{biber} 编译。
+
+为了方便文献样式修改，模板引入了 \lstinline{bibstyle} 和 \lstinline{citestyle} 选项，默认均为数字格式（numeric），如果需要设置为国标 GB7714-2015，需要使用：
+\begin{lstlisting}
+  \documentclass[citestyle=gb7714-2015, bibstyle=gb7714-2015]{elegantbook} 
+\end{lstlisting}
+
+如果需要添加排序方式，可以在导言区加入
+\begin{lstlisting}
+  \ExecuteBibliographyOptions{sorting=ynt}
+\end{lstlisting}
+
+启用国标之后，可以加入 \lstinline{sorting=gb7714-2015}。
+
+\section{添加序章}
+
+如果你想在第一章前面添序章，不改变原本章节序号，可以在第一章内容前面使用 
+\begin{lstlisting}
+\chapter*{Introduction}
+\markboth{Introduction}{Introduction}
+The content of introduction.
+\end{lstlisting}
+
+\section{目录选项与深度}
+本模板添加了一个目录选项 \lstinline{toc}，可以设置目录为单栏（\lstinline{onecol}）和双栏（\lstinline{twocol}）显示，比如双栏显示可以使用
+\begin{lstlisting}
+\documentclass[twocol]{elegantbook}
+\documentclass[toc=twocol]{elegantbook}
+\end{lstlisting}
+
+默认本模板目录深度为 1，你可以在导言区使用
+\begin{lstlisting}
+\setcounter{tocdepth}{2}
+\end{lstlisting}
+将其修改为 2 级目录（章与节）显示。
+
+
+\section{章节摘要}
+模板新增了一个章节摘要环境（introduction），使用示例
+\begin{lstlisting}
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+\end{lstlisting}
+效果如下：
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+
+环境的标题文字可以通过这个环境的可选参数进行修改，修改方法为：
+\begin{lstlisting}
+\begin{introduction}[Brief Introduction]
+...
+\end{introduction}
+\end{lstlisting}
+
+\section{章后习题}
+前面我们介绍了例题和练习两个环境，这里我们再加一个，章后习题（\lstinline{problemset}）环境，用于在每一章结尾，显示本章的练习。使用方法如下
+
+\begin{lstlisting}
+\begin{problemset}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+\end{problemset}
+\end{lstlisting}
+
+
+效果如下：
+\begin{problemset}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+  \item 测试数学公式
+  \begin{equation}
+    a^2+b^2=c_{2_{i}} (1,2) [1,23]
+  \end{equation}
+\end{problemset}
+
+\begin{remark}
+如果你想把 \lstinline{problemset} 环境的标题改为其他文字，你可以类似于 introduction 环境修改 problemset 的可选参数。另外，目前这个环境会自动出现在目录中，但是不会出现在页眉页脚信息中（待解决）。
+\end{remark}
+
+\begin{solution}
+如果你想把 \lstinline{problemset} 环境的标题改为其他文字，你可以类似于 introduction 环境修改 problemset 的可选参数。另外，目前这个环境会自动出现在目录中，但是不会出现在页眉页脚信息中（待解决）。
+\end{solution}
+
+\section{旁注}
+
+在 3.08 版本中，我们引入了 旁注设置选项 \lstinline{marginpar=margintrue} 以及测试命令 \lstinline{\elegantpar} ，但是由此带来一堆问题。我们决定在 3.09 版本中将其删除，并且，在旁注命令得到大幅度优化之前，不会将此命令再次引入书籍模板中。对此造成各位用户的不方便，非常抱歉！不过我们保留了 \lstinline{marginpar} 这个选项，你可以使用 \lstinline{marginpar=margintrue} 获得保留右侧旁注的版面设计。然后使用系统自带的 \lstinline{\marginpar} 或者 \lstinline{marginnote} 宏包的 \lstinline{\marginnote} 命令。
+
+\begin{remark}
+在使用旁注的时候，需要注意的是，文本和公式可以直接在旁注中使用。
+
+\begin{lstlisting}
+% text
+\marginpar{margin paragraph text}
+
+% equation
+\marginpar{
+  \begin{equation}
+    a^2 + b^2 = c^2
+  \end{equation}
+}
+\end{lstlisting}
+
+但是浮动体（表格、图片）需要注意，不能用浮动体环境，需要使用直接插图命令或者表格命令环境。然后使用 \lstinline{\captionof} 为其设置标题。为了得到居中的图表，可以使用 \lstinline{\centerline} 命令或者 \lstinline{center} 环境。更多详情请参考：\href{https://tex.stackexchange.com/questions/5583/caption-of-figure-in-marginpar-and-caption-of-wrapfigure-in-margin}{Caption of Figure in Marginpar}。
+
+\begin{lstlisting}
+% graph with centerline command
+\marginpar{
+  \centerline{
+    \includegraphics[width=0.2\textwidth]{logo.png}
+  }
+  \captionof{figure}{your figure caption}
+}
+
+% graph with center environment
+\marginpar{
+  \begin{center}
+    \includegraphics[width=0.2\textwidth]{logo.png}
+    \captionof{figure}{your figure caption}
+  \end{center}
+}
+\end{lstlisting}
+
+\end{remark}
+
+\chapter{字体选项}
+字体选项独立成章的原因是，我们希望本模板的用户关心模板使用的字体，知晓自己使用的字体以及遇到字体相关的问题能更加便捷地找到答案。
+
+\textcolor{red}{\bfseries 重要提示}：从 3.10 版本更新之后，沿用至今的 newtx 系列字体被重新更改为 cm 字体。并且新增中文字体（\lstinline{chinesefont}）选项。
+
+\section{数学字体选项}
+
+本模板定义了一个数学字体选项（\lstinline{math}），可选项有三个：
+\begin{enumerate}
+  \item \lstinline{math=cm}（默认），使用 \LaTeX{} 默认数学字体（推荐，无需声明）；
+  \item \lstinline{math=newtx}，使用 \lstinline{newtxmath} 设置数学字体（潜在问题比较多）。
+  \item \lstinline{math=mtpro2}，使用 \lstinline{mtpro2} 宏包设置数学字体，要求用户已经成功安装此宏包。
+\end{enumerate}
+
+\section{使用 newtx 系列字体}
+
+如果需要使用原先版本的 \lstinline{newtx} 系列字体，可以通过显示声明数学字体：
+
+\begin{lstlisting}
+\documentclass[math=newtx]{elegantbook}
+\end{lstlisting}
+
+\subsection{连字符}
+
+如果使用 \lstinline{newtx} 系列字体宏包，需要注意下连字符的问题。
+\begin{equation}
+  \int_{R^q} f(x,y) dy.\emph{of\kern0pt f}
+\end{equation}
+的代码为
+\begin{lstlisting}
+\begin{equation}
+  \int_{R^q} f(x,y) dy.\emph{of \kern0pt f}
+\end{equation}
+\end{lstlisting}
+
+\subsection{宏包冲突}
+
+另外在 3.08 版本中，有用户反馈模板在和 \lstinline{yhmath} 以及 \lstinline{esvect} 等宏包搭配使用的时候会出现报错：
+\begin{lstlisting}
+LaTeX Error:
+   Too many symbol fonts declared.
+\end{lstlisting}
+
+原因是在使用 \lstinline{newtxmath} 宏包时，重新定义了数学字体用于大型操作符，达到了 {\heiti 最多 16 个数学字体} 的上限，在调用其他宏包的时候，无法新增数学字体。为了减少调用非常用宏包，在此给出如何调用 \lstinline{yhmath} 以及 \lstinline{esvect} 宏包的方法。
+
+请在 \lstinline{elegantbook.cls} 内搜索 \lstinline{yhmath} 或者 \lstinline{esvect}，将你所需要的宏包加载语句\textit{取消注释}即可。
+\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{中文字体选项}
+模板从 3.10 版本提供中文字体选项 \lstinline{chinesefont}，可选项有
+\begin{enumerate}
+\item \lstinline{ctexfont}：默认选项，使用 \lstinline{ctex} 宏包根据系统自行选择字体，可能存在字体缺失的问题，更多内容参考 \lstinline{ctex} 宏包\href{https://ctan.org/pkg/ctex}{官方文档}\footnote{可以使用命令提示符，输入 \lstinline{texdoc ctex} 调出本地 \lstinline{ctex} 宏包文档}。
+\item \lstinline{founder}：方正字体选项，调用 \lstinline{ctex} 宏包并且使用 \lstinline{fontset=none} 选项，然后设置字体为方正四款免费字体，方正字体下载注意事项见后文。
+\item \lstinline{nofont}：调用 \lstinline{ctex} 宏包并且使用 \lstinline{fontset=none} 选项，不设定中文字体，用户可以自行设置中文字体，具体见后文。
+\end{enumerate}
+
+\begin{remark}
+  使用 \lstinline{founder} 选项或者 \lstinline{nofont} 时，必须使用 \hologo{XeLaTeX} 进行编译。
+\end{remark}
+
+\subsection{方正字体选项}
+由于使用 \lstinline{ctex} 宏包默认调用系统已有的字体，部分系统字体缺失严重，因此，用户希望能够使用其它字体，我们推荐使用方正字体。方正的{\songti 方正书宋}、{\heiti 方正黑体}、{\kaishu 方正楷体}、{\fangsong 方正仿宋}四款字体均可免费试用，且可用于商业用途。用户可以自行从\href{http://www.foundertype.com/}{方正字体官网}下载此四款字体，在下载的时候请\textbf{务必}注意选择 GBK 字符集，也可以使用 \href{https://www.latexstudio.net/}{\LaTeX{} 工作室}提供的\href{https://pan.baidu.com/s/1BgbQM7LoinY7m8yeP25Y7Q}{方正字体，提取码为：njy9} 进行安装。安装时，{\kaishu Win 10 用户请右键选择为全部用户安装，否则会找不到字体。}
+
+\begin{figure}[!htb]
+\centering
+\includegraphics[width=0.9\textwidth]{founder.png}
+\end{figure}
+
+\subsection{其他中文字体}
+如果你想完全自定义字体\footnote{这里仍然以方正字体为例。}，你可以选择 \lstinline{chinesefont=nofont}，然后在导言区设置
+\begin{lstlisting}
+\setCJKmainfont[BoldFont={FZHei-B01},ItalicFont={FZKai-Z03}]{FZShuSong-Z01}
+\setCJKsansfont[BoldFont={FZHei-B01},ItalicFont={FZHei-B01}]{FZHei-B01}
+\setCJKmonofont[BoldFont={FZHei-B01},ItalicFont={FZHei-B01}]{FZFangSong-Z02}
+\setCJKfamilyfont{zhsong}{FZShuSong-Z01}
+\setCJKfamilyfont{zhhei}{FZHei-B01}
+\setCJKfamilyfont{zhkai}{FZKai-Z03}
+\setCJKfamilyfont{zhfs}{FZFangSong-Z02}
+\newcommand*{\songti}{\CJKfamily{zhsong}}
+\newcommand*{\heiti}{\CJKfamily{zhhei}}
+\newcommand*{\kaishu}{\CJKfamily{zhkai}}
+\newcommand*{\fangsong}{\CJKfamily{zhfs}}
+\end{lstlisting}
+
+\chapter{ElegantBook 写作示例}
+
+\begin{introduction}
+  \item 积分定义~\ref{def:int}
+  \item Fubini 定理~\ref{thm:fubi}
+  \item 最优性原理~\ref{pro:max}
+  \item 柯西列性质~\ref{property:cauchy}
+  \item 韦达定理
+\end{introduction}
+
+\section{Lebesgue 积分}
+在前面各章做了必要的准备后，本章开始介绍新的积分。在 Lebesgue 测度理论的基础上建立了 Lebesgue 积分，其被积函数和积分域更一般，可以对有界函数和无界函数统一处理。正是由于 Lebesgue 积分的这些特点，使得 Lebesgue 积分比 Riemann 积分具有在更一般条件下的极限定理和累次积分交换积分顺序的定理，这使得 Lebesgue 积分不仅在理论上更完善，而且在计算上更灵活有效。
+
+Lebesgue 积分有几种不同的定义方式。我们将采用逐步定义非负简单函数，非负可测函数和一般可测函数积分的方式。
+
+由于现代数学的许多分支如概率论、泛函分析、调和分析等常常用到一般空间上的测度与积分理论，在本章最后一节将介绍一般的测度空间上的积分。
+
+\subsection{积分的定义}
+
+我们将通过三个步骤定义可测函数的积分。首先定义非负简单函数的积分。以下设 $E$ 是 $\mathcal{R}^n$ 中的可测集。
+
+\begin{definition}[可积性] \label{def:int} 
+设 $ f(x)=\sum\limits_{i=1}^{k} a_i \chi_{A_i}(x)$ 是 $E$ 上的非负简单函数，其中 $\{A_1,A_2,\ldots,A_k\}$ 是 $E$ 上的一个可测分割，$a_1,a_2,\ldots,a_k$ 是非负实数。定义 $f$ 在 $E$ 上的积分为 $\int_{a}^b f(x)$
+\begin{equation}
+   \label{inter}
+   \int_{E} f dx = \sum_{i=1}^k a_i m(A_i) \pi \alpha\beta\sigma\gamma\nu\xi\epsilon\varepsilon. \oint_{a}^b\ointop_{a}^b\prod_{i=1}^n
+\end{equation}
+一般情况下 $0 \leq \int_{E} f dx \leq \infty$。若 $\int_{E} f dx < \infty$，则称 $f$ 在 $E$ 上可积。
+\end{definition}
+
+一个自然的问题是，Lebesgue 积分与我们所熟悉的 Riemann 积分有什么联系和区别？在 4.4 在我们将详细讨论 Riemann 积分与 Lebesgue 积分的关系。这里只看一个简单的例子。设 $D(x)$ 是区间 $[0,1]$ 上的 Dirichlet 函数。即 $D(x)=\chi_{Q_0}(x)$，其中 $Q_0$ 表示 $[0,1]$ 中的有理数的全体。根据非负简单函数积分的定义，$D(x)$ 在 $[0,1]$ 上的 Lebesgue 积分为
+\begin{equation}
+   \label{inter2}
+   \int_0^1 D(x)dx = \int_0^1 \chi_{Q_0} (x) dx = m(Q_0) = 0
+\end{equation}
+即 $D(x)$ 在 $[0,1]$ 上是 Lebesgue 可积的并且积分值为零。但 $D(x)$ 在 $[0,1]$ 上不是 Riemann 可积的。
+
+
+有界变差函数是与单调函数有密切联系的一类函数。有界变差函数可以表示为两个单调递增函数之差。与单调函数一样，有界变差函数几乎处处可导。与单调函数不同，有界变差函数类对线性运算是封闭的，它们构成一线空间。练习题 \ref{exer:43} 是一个性质的证明。
+
+\begin{exercise}\label{exer:43}
+设 $f \notin\in L(\mathcal{R}^1)$，$g$ 是 $\mathcal{R}^1$ 上的有界可测函数。证明函数
+\begin{equation}
+   \label{ex:1}
+   I(t) = \int_{\mathcal{R}^1} f(x+t)g(x)dx \quad t \in \mathcal{R}^1
+\end{equation}
+是 $\mathcal{R}^1$ 上的连续函数。 
+\end{exercise}
+
+\begin{solution}
+即 $D(x)$ 在 $[0,1]$ 上是 Lebesgue 可积的并且积分值为零。但 $D(x)$ 在 $[0,1]$ 上不是 Riemann 可积的。
+\end{solution}
+
+\begin{proof}
+即 $D(x)$ 在 $[0,1]$ 上是 Lebesgue 可积的并且积分值为零。但 $D(x)$ 在 $[0,1]$ 上不是 Riemann 可积的。
+\end{proof}
+
+\begin{theorem}[Fubini 定理] \label{thm:fubi} 
+（1）若 $f(x,y)$ 是 $\mathcal{R}^p\times\mathcal{R}^q$ 上的非负可测函数，则对几乎处处的 $x\in \mathcal{R}^p$，$f(x,y)$ 作为 $y$ 的函数是 $\mathcal{R}^q$ 上的非负可测函数，$g(x)=\int_{\mathcal{R}^q}f(x,y) dy$ 是 $\mathcal{R}^p$ 上的非负可测函数。并且
+\begin{equation}
+   \label{eq:461}
+   \int_{\mathcal{R}^p\times\mathcal{R}^q} f(x,y) dxdy=\int_{\mathcal{R}^p}\left(\int_{\mathcal{R}^q}f(x,y)dy\right)dx.
+\end{equation}
+
+（2）若 $f(x,y)$ 是 $\mathcal{R}^p\times\mathcal{R}^q$ 上的可积函数，则对几乎处处的 $x\in\mathcal{R}^p$，$f(x,y)$ 作为 $y$ 的函数是 $\mathcal{R}^q$ 上的可积函数，并且 $g(x)=\int_{\mathcal{R}^q}f(x,y) dy$ 是 $\mathcal{R}^p$ 上的可积函数。而且~\ref{eq:461} 成立。
+\end{theorem}
+
+\ref{thm:fubi}
+
+\begin{note}
+在本模板中，引理（lemma），推论（corollary）的样式和定理~\ref{thm:fubi} 的样式一致，包括颜色，仅仅只有计数器的设置不一样。
+\end{note}
+
+我们说一个实变或者复变量的实值或者复值函数是在区间上平方可积的，如果其绝对值的平方在该区间上的积分是有限的。所有在勒贝格积分意义下平方可积的可测函数构成一个希尔伯特空间，也就是所谓的 $L^2$ 空间，几乎处处相等的函数归为同一等价类。形式上，$L^2$ 是平方可积函数的空间和几乎处处为 0 的函数空间的商空间。
+
+\begin{proposition}[最优性原理] \label{pro:max}
+如果 $u^*$ 在 $[s,T]$ 上为最优解，则 $u^*$ 在 $[s, T]$ 任意子区间都是最优解，假设区间为 $[t_0, t_1]$ 的最优解为 $u^*$ ，则 $u(t_0)=u^{*}(t_0)$，即初始条件必须还是在 $u^*$ 上。
+\end{proposition}
+
+我们知道最小二乘法可以用来处理一组数据，可以从一组测定的数据中寻求变量之间的依赖关系，这种函数关系称为经验公式。本课题将介绍最小二乘法的精确定义及如何寻求点与点之间近似成线性关系时的经验公式。假定实验测得变量之间的 $n$ 个数据，则在平面上，可以得到 $n$ 个点，这种图形称为 “散点图”，从图中可以粗略看出这些点大致散落在某直线近旁, 我们认为其近似为一线性函数，下面介绍求解步骤。
+
+\begin{figure}[htbp]
+  \centering
+  \includegraphics[width=0.6\textwidth]{scatter.jpg}
+  \caption{散点图示例 $\hat{y}=a+bx$ \label{fig:scatter}}
+\end{figure}
+
+以最简单的一元线性模型来解释最小二乘法。什么是一元线性模型呢？监督学习中，如果预测的变量是离散的，我们称其为分类（如决策树，支持向量机等），如果预测的变量是连续的，我们称其为回归。回归分析中，如果只包括一个自变量和一个因变量，且二者的关系可用一条直线近似表示，这种回归分析称为一元线性回归分析。如果回归分析中包括两个或两个以上的自变量，且因变量和自变量之间是线性关系，则称为多元线性回归分析。对于二维空间线性是一条直线；对于三维空间线性是一个平面，对于多维空间线性是一个超平面。
+
+\begin{property}\label{property:cauchy}
+柯西列的性质
+\begin{enumerate}
+\item $\{x_k\}$ 是柯西列，则其子列 $\{x_k^i\}$ 也是柯西列。
+\item $x_k\in \mathcal{R}^n$，$\rho(x,y)$ 是欧几里得空间，则柯西列收敛，$(\mathcal{R}^n,\rho)$ 空间是完备的。
+\end{enumerate}
+\end{property}
+
+\begin{conclusion}
+回归分析（regression analysis) 是确定两种或两种以上变量间相互依赖的定量关系的一种统计分析方法。运用十分广泛，回归分析按照涉及的变量的多少，分为一元回归和多元回归分析；按照因变量的多少，可分为简单回归分析和多重回归分析；按照自变量和因变量之间的关系类型，可分为线性回归分析和非线性回归分析。
+\end{conclusion}
+
+\begin{problemset}
+\item 设 $A$ 为数域 $K$ 上的 $n$ 级矩阵。证明：如果 $K^n$ 中任意非零列向量都是 $A$ 的特征向量，则 $A$ 一定是数量矩阵。
+\item 证明：不为零矩阵的幂零矩阵不能对角化。
+\item 设 $A = (a_{ij})$ 是数域 $K$ 上的一个 $n$ 级上三角矩阵，证明：如果 $a_{11} = a_{22} = \cdots = a_{nn}$，并且至少有一个 $a_{kl} \not = 0 (k < l)$，则 $A$ 一定不能对角化。
+\end{problemset}
+
+\chapter{常见问题集}
+
+我们根据用户社区反馈整理了下面一些常见的问题，用户在遇到问题时，应当首先查阅本手册和本部分的常见的问题。
+
+\begin{enumerate}[itemsep=1.5ex]
+  \item \question{有没有办法章节用“第一章，第一节，（一）”这种？}
+    见前文介绍，可以使用 \lstinline{scheme=chinese} 设置。
+  \item \question{大佬，我想把正文字体改为亮色，背景色改为黑灰色。}
+    页面颜色可以使用 \lstinline{\pagecolor} 命令设置，文本命令可以参考\href{https://tex.stackexchange.com/questions/278544/xcolor-what-is-the-equivalent-of-default-text-color}{这里}进行设置。
+  \item \question{\lstinline[breaklines]{Package ctex Error: CTeX fontset `Mac' is unavailable.}}
+    在 Mac 系统下，中文编译请使用 \hologo{XeLaTeX}。
+  \item \question{\lstinline{! LaTeX Error: Unknown option `scheme=plain' for package `ctex'.}}
+    你用的 C\TeX{} 套装吧？这个里面的 \lstinline{ctex} 宏包已经是已经是 10 年前的了，与本模板使用的 \lstinline{ctex} 宏集有很大区别。不建议 C\TeX{} 套装了，请卸载并安装 \TeX{} Live 2021。
+  \item \question{我该使用什么版本？}
+    请务必使用\href{https://github.com/ElegantLaTeX/ElegantBook/releases}{最新正式发行版}，发行版间不定期可能会有更新（修复 bug 或者改进之类），如果你在使用过程中没有遇到问题，不需要每次更新\href{https://github.com/ElegantLaTeX/ElegantBook/archive/master.zip}{最新版}，但是在发行版更新之后，请尽可能使用最新版（发行版）！最新发行版可以在 GitHub 或者 \TeX{} Live 2021 内获取。
+  \item \question{我该使用什么编辑器？}
+    你可以使用 \TeX{} Live 2021 自带的编辑器 \TeX{}works 或者使用 \TeX{}studio，\TeX works 的自动补全，你可以参考我们的总结 \href{https://github.com/EthanDeng/texworks-autocomplete}{\TeX works 自动补全}。推荐使用 \TeX{} Live 2021 + \TeX{}studio。我自己用 VS Code 和 Sublime Text，相关的配置说明，请参考 \href{https://github.com/EthanDeng/vscode-latex}{\LaTeX{} 编译环境配置：Visual Studio Code 配置简介} 和 \href{https://github.com/EthanDeng/sublime-text-latex}{Sublime Text 搭建 \LaTeX{} 编写环境}。
+  \item \question{您好，我们想用您的 ElegantBook 模板写一本书。关于机器学习的教材，希望获得您的授权，谢谢您的宝贵时间。}
+    模板的使用修改都是自由的，你们声明模板来源以及模板地址（GitHub 地址）即可，其他未尽事宜按照开源协议 LPPL-1.3c。做好之后，如果方便的话，可以给我们一个链接，我把你们的教材放在 Elegant\LaTeX{} 用户作品集里。
+  \item \question{请问交叉引用是什么？}
+    本群和本模板适合有一定 \LaTeX{} 基础的用户使用，新手请先学习 \LaTeX{} 的基础，理解各种概念，否则你将寸步难行。
+  \item \question{定义等环境中无法使用加粗命令么？}
+    是这样的，默认中文并没加粗命令，如果你想在定义等环境中使用加粗命令，请使用 \lstinline{\heiti} 等字体命令，而不要使用 \lstinline{\textbf}。或者，你可以将 \lstinline|\textbf| 重新定义为 \lstinline|\heiti|。英文模式不存在这个问题。
+  \item \question{代码高亮环境能用其他语言吗？}
+    可以的，ElegantBook 模板用的是 \lstinline{listings} 宏包，你可以在环境（\lstinline{lstlisting}）之后加上语言（比如 Python 使用 \lstinline{language=Python} 选项），全局语言修改请使用 \lstinline{lsset} 命令，更多信息请参考宏包文档。
+  \item \question{群主，什么时候出 Beamer 的模板（主题），ElegantSlide 或者 ElegantBeamer？}
+    由于 Beamer 中有一个很优秀的主题 \href{https://github.com/matze/mtheme}{Metropolis}。后续确定不会再出任何主题/模板，请大家根据需要修改已有主题。
+\end{enumerate}
+
+\chapter{版本更新历史}
+
+根据用户的反馈，我们不断修正和完善模板。截止到此次更新，ElegantBook 模板在 GitHub 上有将近 100 次提交，正式发行版本（release）有 17 次。由于 3.00 之前版本与现在版本差异非常大，在此不列出 3.00 之前的更新内容。
+
+
+
+\datechange{2022/03/08}{版本 4.2 正式发布。}
+
+\begin{change}
+  \item 对于 newtx 系列宏包更新导致的字体 bug 的修复；
+  \item 修缮目录格式，为了达到这个目的，重新改写 \lstinline{\chaptername} 的重定义语句；
+  \item 增加日语 \lstinline{lang=jp} 设定。
+  \item 这个版本为一个临时性版本，在 \TeX Live 2022 发布之后，将尽快发布 4.3 版本，由于对于中文的改动比较大，可能会出现预期之外的 bug，有问题可以在 QQ 群或者 Github 反馈。
+\end{change}
+
+
+\datechange{2021/05/02}{版本 4.1 正式发布。}
+
+\begin{change}
+  \item \textbf{重要改动}：由原先的 \hologo{BibTeX} 改为 biblatex 编译方式（后端为 \lstinline{biber}），请注意两者之间的差异；
+  \item \textbf{重要改进}：修改对于定理写法兼容方式，提高数学公式代码的兼容性；
+  \item 页面设置改动，默认页面更宽；方便书写和阅读；
+  \item 支持目录文字以及页码跳转；
+  \item 不再维护 \hologo{pdfLaTeX} 中文支持方式，请务必使用 \hologo{XeLaTeX} 编译中文文稿。
+  \item 增加多个语言选项，法语 \lstinline{lang=fr}、荷兰语 \lstinline{lang=nl}、匈牙利语 \lstinline{lang=hu}、西班牙语 \lstinline{lang=es}、蒙古语 \lstinline{lang=mn} 等。
+\end{change}
+
+
+\datechange{2020/04/12}{版本 3.11 正式发布，\textcolor{red}{此版本为 3.x 最后版本。}}
+
+\begin{change}
+  \item \textbf{重要修正}：修复因为 \lstinline{gbt7714} 宏包更新导致的 \lstinline{natbib option clash} 错误；
+  \item 由于 \lstinline{pgfornament} 宏包未被 \TeX{} Live 2020 收录，因此删除 base 相关的内容；
+  \item 修复部分环境的空格问题；
+  \item 增加了意大利语言选项 \lstinline{lang=it}。
+\end{change}
+
+
+\datechange{2020/02/10}{版本 3.10 正式发布}
+
+\begin{change}
+  \item 增加数学字体选项 \lstinline{math}，可选项为 \lstinline{newtx} 和 \lstinline{cm}。\\
+  \textbf{重要提示}：原先通过 \lstinline{newtxmath} 宏包设置的数学字体改为 \LaTeX{} 默认数学字体，如果需要保持原来的字体，需要显式声明数学字体（\lstinline{math=newtx}）；
+  \item 新增中文字体选项 \lstinline{chinesefont}，可选项为 \lstinline{ctexfont}、\lstinline{founder} 和 \lstinline{nofont}。
+  \item 将封面作者信息设置为可选，并且增加自定义信息命令 \lstinline{\bioinfo}；
+  \item 在说明文档中增加版本历史，新增 \lstinline{\datechange} 命令和 \lstinline{change} 环境；
+  \item 增加汉化章节选项 \lstinline{scheme}，可选项为汉化 \lstinline{chinese}；
+  \item 由于 \lstinline{\lvert} 问题已经修复，重新调整 \lstinline{ctex} 宏包和 \lstinline{amsmath} 宏包位置。
+  \item 修改页眉设置，去除了 \lstinline{\lastpage} 以避免 page anchor 问题，加入 \lstinline{\frontmatter}。
+  \item 修改参考文献选项 \lstinline{cite}，可选项为数字 \lstinline{numbers}、 作者-年份 \lstinline{authoryear} 以及上标 \lstinline{super}。
+  \item 新增参考文献样式选项 \lstinline{bibstyle}，并将英文模式下参考文献样式 \lstinline{apalike} 设置为默认值，中文仍然使用 \lstinline{gbt7714} 宏包设置。
+\end{change}
+
+\datechange{2019/08/18}{版本 3.09 正式发布}
+
+\begin{change}
+  \item \lstinline{\elegantpar} 存在 bug，删除 \lstinline{\elegantpar} 命令，建议用户改用 \lstinline{\marginnote} 和 \lstinline{\marginpar} 旁注命令。
+  \item 积分操作符统一更改为 \lstinline{esint} 宏包设置；
+  \item 新增目录选项 \lstinline{toc}，可选项为单栏 \lstinline{onecol} 和双栏 \lstinline{twocol}；
+  \item 手动增加参考文献选项 \lstinline{cite}，可选项为上标形式 \lstinline{super}；
+  \item 修正章节习题（\lstinline{problemset}）环境。
+\end{change}
+
+\datechange{2019/05/28}{版本 3.08 正式发布}
+
+\begin{change}
+  \item 修复 \lstinline{\part} 命令。
+  \item 引入 Note 模板中的 \lstinline{pad} 选项 \lstinline{device=pad}。
+  \item 数学字体加入 \lstinline{mtpro2} 可选项 \lstinline{math=mtpro2}，使用免费的 \lstinline{lite} 子集。
+  \item 将参考文献默认显示方式 \lstinline{authoyear} 改为 \lstinline{numbers}。
+  \item 引入旁注命令 \lstinline{\marginpar}（测试）。
+  \item 新增章节摘要环境 \lstinline{introduction}。
+  \item 新增章节习题环境 \lstinline{problemset}。
+  \item 将 \lstinline{\equote} 重命名为 \lstinline{\extrainfo}。
+  \item 完善说明文档，增加致谢部分。
+\end{change}
+
+\datechange{2019/04/15}{版本 3.07 正式发布}
+
+\begin{change}
+  \item 删除中英文自定义字体总设置。
+  \item 新增颜色主题，并将原绿色默认主题设置为蓝色 \lstinline{color=blue}。
+  \item 引入隐藏装饰图案选项 \lstinline{base}，可选项有显示 \lstinline{show} 和隐藏 \lstinline{hide}。
+  \item 新增定理模式 \lstinline{mode}，可选项有简单模式 \lstinline{simple} 和炫彩模式 \lstinline{fancy}。
+  \item 新增隐藏证明、答案等环境的选项 \lstinline{result=noanswer}。
+\end{change}
+
+\datechange{2019/02/25}{版本 3.06 正式发布}
+
+\begin{change}
+  \item 删除水印。
+  \item 新封面，新装饰图案。
+  \item 添加引言使用说明。
+  \item 修复双面 \lstinline{twoside}。
+  \item 美化列表环境。
+  \item 增加 \lstinline{\subsubsection} 的设置。
+  \item 将模板拆分成中英文语言模式。
+  \item 使用 \lstinline{lstlisting} 添加代码高亮。
+  \item 增加定理类环境使用说明。
+\end{change}
+
+\datechange{2019/01/22}{版本 3.05 正式发布}
+
+\begin{change}
+  \item 添加 \lstinline{xeCJK} 宏包中文支持方案。
+  \item 修复模板之前对 Ti\textit{k}Z 单位的改动。
+  \item 更新 logo 图。
+\end{change}
+
+\datechange{2019/01/15}{版本 3.04 正式发布}
+
+\begin{change}
+  \item 格式化模板代码。
+  \item 增加 \lstinline{\equote} 命令。
+  \item 修改 \lstinline{\date}。
+\end{change}
+
+\datechange{2019/01/08}{版本 3.03 正式发布}
+
+\begin{change}
+  \item 修复附录章节显示问题。
+  \item 小幅优化封面代码。
+\end{change}
+
+\datechange{2018/12/31}{版本 3.02 正式发布}
+
+\begin{change}
+  \item 修复名字系列命令自定义格式时出现的空格问题，比如 \lstinline{\listfigurename}。
+  \item 英文定理类名字改为中文名。
+  \item 英文结构名改为中文。
+\end{change}
+
+\datechange{2018/12/16}{版本 3.01 正式发布}
+
+\begin{change}
+  \item 调整 \lstinline{ctex} 宏包。
+  \item 说明文档增加更新内容。
+\end{change}
+
+\datechange{2018/12/06}{版本 3.00 正式发布}
+
+\begin{change}
+  \item 删除 \lstinline{mathpazo} 数学字体选项。
+  \item 添加邮箱命令 \lstinline{\mailto}。
+  \item 修改英文字体为 \lstinline{newtx} 系列，另外大型操作符号维持 cm 字体。
+  \item 中文字体改用 \lstinline{ctex} 宏包自动设置。
+  \item 删除 \lstinline{xeCJK} 字体设置，原因是不同系统字体不方便统一。
+  \item 定理换用 \lstinline{tcolobox} 宏包定义，并基本维持原有的定理样式，优化显示效果，支持跨页；定理类名字重命名，如 etheorem 改为 theorem 等等。
+  \item 删去自定义的缩进命令 \lstinline{\Eindent}。
+  \item 添加参考文献宏包 \lstinline{natbib}。
+  \item 颜色名字重命名。
+\end{change}
+
+\nocite{*}
+\printbibliography[heading=bibintoc, title=\ebibname]
+\appendix
+
+\chapter{基本数学工具}
+
+
+本附录包括了计量经济学中用到的一些基本数学，我们扼要论述了求和算子的各种性质，研究了线性和某些非线性方程的性质，并复习了比例和百分数。我们还介绍了一些在应用计量经济学中常见的特殊函数，包括二次函数和自然对数，前 4 节只要求基本的代数技巧，第 5 节则对微分学进行了简要回顾；虽然要理解本书的大部分内容，微积分并非必需，但在一些章末附录和第 3 篇某些高深专题中，我们还是用到了微积分。
+
+\section{求和算子与描述统计量}
+
+\textbf{求和算子} 是用以表达多个数求和运算的一个缩略符号，它在统计学和计量经济学分析中扮演着重要作用。如果 $\{x_i: i=1, 2, \ldots, n\}$ 表示 $n$ 个数的一个序列，那么我们就把这 $n$ 个数的和写为：
+
+\begin{equation}
+\sum_{i=1}^n x_i \equiv x_1 + x_2 +\cdots + x_n
+\end{equation}
+
+
+
+\end{document}

elegantbook-en.tex

@@ -0,0 +1,718 @@
+\documentclass[11pt,fancy]{elegantbook}
+
+\title{An Elegant \LaTeX{} Template for Books}
+\subtitle{Classic Elegant\LaTeX{} Template}
+
+\author{Ethan Deng \& Liam Huang}
+\institute{Elegant\LaTeX{} Program}
+\date{March 8, 2022}
+\version{4.2}
+\bioinfo{Bio}{Information}
+
+\extrainfo{Victory won\rq t come to us unless we go to it. }
+
+\logo{logo-blue.png}
+\cover{cover.jpg}
+
+\definecolor{customcolor}{RGB}{32,178,170}
+\colorlet{coverlinecolor}{customcolor}
+
+
+\begin{document}
+
+\maketitle
+
+\frontmatter
+\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 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}
+
+Version 4.2 is the \textit{temporary} version before v4.3 which will be released when \TeX Live 2022 is ready, we add quick bug fix caused by newtx package updates, and multilingual translation \lstinline{lang=jp}. What\rq s new in this version:
+
+\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}.
+  \item \textbf{! Warnings}: Due to this `urgent' fonts bug and TOC modification, the multilingual option may cause some unexpected errors, you can report in this \href{https://github.com/ElegantLaTeX/ElegantBook/issues/170}{issue}, I will fix it after the releases of \TeX{} Live 2022.
+\end{change}
+
+
+\section{Installation and Update}
+Both portable version and installation package are available, 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{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:
+\begin{lstlisting}
+tlmgr update --self 
+tlmgr update --all
+\end{lstlisting}
+
+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 2018/2019/2020 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 2021 (default: \lstinline|C:\texlive\2021\texmf-dist\tex\latex\elegantbook| ), run \lstinline{texhash} in cmd.
+
+\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.
+
+
+\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 2021, either \hologo{pdfLaTeX} or \hologo{XeLaTeX} works fine. \hologo{XeLaTeX} is preferred for Chinese articles.
+
+\section{Languages}
+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}.
+\end{itemize}
+
+\begin{remark}
+Chinese Characters  are acceptable \textbf{ONLY} in \lstinline{lang=cn}.
+\end{remark}
+
+\section{Device Mode Option}
+The option for device (\lstinline{device}) was originally used in ElegantNote, now we include this option in ElegantBook\footnote{Pictures have to be modified accordingly.} as well. Activate iPad mode in the following way\footnote{Default size: normal, A4 paper.}:
+\begin{lstlisting}
+\documentclass[pad]{elegantbook} %or
+\documentclass[device=pad]{elegantbook}
+\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
+\begin{lstlisting}
+\documentclass[green]{elegantbook} %or
+\documentclass[color=green]{elegantbook}
+\end{lstlisting}
+
+
+\begin{table}[htbp]
+\caption{ElegantBook Themes\label{tab:color thm}}
+\centering
+\begin{tabular}{ccccccc}
+\toprule
+          & \textcolor{structure1}{green} 
+          & \textcolor{structure2}{cyan} 
+          & \textcolor{structure3}{blue}
+          & \textcolor{structure4}{gray} 
+          & \textcolor{structure5}{black} 
+          & Main Environments\\
+\midrule
+structure & \makecell{{\color{structure1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{structure2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{structure3}\rule{1cm}{1cm}}} 
+        & \makecell{{\color{structure4}\rule{1cm}{1cm}}} 
+        & \makecell{{\color{structure5}\rule{1cm}{1cm}}} 
+        & chapter  section  subsection \\
+main      & \makecell{{\color{main1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main5}\rule{1cm}{1cm}}}
+        & definition  exercise  problem  \\
+second    & \makecell{{\color{second1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second5}\rule{1cm}{1cm}}}
+        & theorem  lemma  corollary\\
+third     & \makecell{{\color{third1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third5}\rule{1cm}{1cm}}}
+        & proposition\\
+\bottomrule
+\end{tabular}
+\end{table}
+
+If you want to customize the colors, please select \lstinline{nocolor} or use \lstinline{color=none} and declare the main, second, and third colors in the preamble section as follows:
+\begin{lstlisting}[frame=single]
+\definecolor{structurecolor}{RGB}{60,113,183}
+\definecolor{main}{RGB}{0,166,82}%
+\definecolor{second}{RGB}{255,134,24}%
+\definecolor{third}{RGB}{0,174,247}% 
+\end{lstlisting}
+
+\section{Cover}
+\subsection{Customized Cover}
+From v3.10, customized cover is allowed, you can choose or hide any element as you prefer. Current optional elements are:
+\begin{itemize}
+  \item title: \lstinline{\title}
+  \item subtitle: \lstinline{\subtitle}
+  \item author: \lstinline{\author}
+  \item institute: \lstinline{\institute}
+  \item date: \lstinline{\date}
+  \item version: \lstinline{\version}
+  \item extra information: \lstinline{\extrainfo}
+  \item cover image: \lstinline{\cover}
+  \item logo: \lstinline{\logo}
+\end{itemize}
+
+Besides, an extra command \lstinline{\bioinfo} is provided with two options--caption and content. For instance, if you want to display \lstinline{Username: 111520}, just type in
+
+\begin{lstlisting}
+\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.
+
+\subsection{Logo}
+Aspect ratio of the logo is 1:1 in this guide, i.e. a square picture. To replace the logo, do remember to choose the appropriate picture.
+
+\subsection{Stylized Cover}
+Want to use stylized cover?(For instance, A4-sized PDF designed by Adobe Illustrator) Please comment out \lstinline{\maketitle} and use \lstinline{pdfpages} to insert the cover. Similar for using \lstinline{titlepage}. If you would like to use the cover in version 2.x, please refer to \href{https://github.com/EthanDeng/etitlepage}{etitlepage}.
+
+\section{Chapter Title Display Styles}
+
+This template contains 2 sets of \textit{title display styles},\lstinline{hang}(default) and \lstinline{display} style. For the former, chapter title is displayed on a single line (\lstinline{hang}). For the latter, chapter title is displayed on a double line (\lstinline{display}).In this guide, we use \lstinline{hang} . To change display style, use:
+\begin{lstlisting}
+\documentclass[hang]{elegantbook} %or
+\documentclass[titlestyle=hang]{elegantbook}
+\end{lstlisting}
+
+
+\section{Introduction of Math Environments}
+We defined two sets of theorem modes, \lstinline{simple} style and \lstinline{fancy} style (default). You may change to \lstinline{simple} mode by
+
+\begin{lstlisting}
+\documentclass[simple]{elegantbook} %or
+\documentclass[mode=simple]{elegantbook}
+\end{lstlisting}
+
+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:
+   \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{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{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.
+\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 text}
+The content of theorem.
+\end{theorem}
+\end{lstlisting}
+
+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:}. 
+
+From version 4.1, you can write your theorem environments as follows:
+\begin{lstlisting}
+\begin{theorem}[theorem name]\label{thm:label text}
+  The content of theorem.
+\end{theorem}
+% or
+\begin{theorem}
+  The content of theorem.
+\end{theorem}
+\end{lstlisting}
+
+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}%
+ 
+
+\subsection{Other Customized Environments}
+The other three math environments can be called directly since there are no additional option for them, e.g. \lstinline{example}:
+\begin{lstlisting}
+\begin{example}
+This is the content of example environment.
+\end{example}
+\end{lstlisting}
+
+The effect is as follows:
+
+\begin{example}
+This is the content of example environment.
+\end{example}
+
+These are all similar environments with slight differences lies in:
+
+\begin{itemize}
+   \item Example, exercise, problem environments number within chapter;
+   \item Note begins with introductory symbol and proof ends with ending symbol;
+   \item Conclusion and other environments are normal paragraph environments with boldfaced introductory words.
+\end{itemize}
+
+
+\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]
+\begin{minipage}[b]{0.49\textwidth}
+\begin{itemize}
+   \item first item of nesti;
+   \item second item of nesti;
+   \begin{itemize}
+      \item first item of nestii;
+      \item second item of nestii;
+      \begin{itemize}
+         \item first item of nestiii;
+         \item second item of nestiii.
+      \end{itemize}   
+   \end{itemize}
+\end{itemize}
+\end{minipage}
+\begin{minipage}[b]{0.49\textwidth}
+\begin{enumerate}
+   \item first item of nesti;
+   \item second item of nesti;
+   \begin{enumerate}
+      \item first item of nestii;
+      \item second item of nestii;
+      \begin{enumerate}
+         \item first item of nestiii;
+         \item second item of nestiii.
+      \end{enumerate}   
+   \end{enumerate}
+\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}
+\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}
+
+\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 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 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.
+
+
+To change the bibliography style, this version introduces \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[citestyle=numeric-comp, bibstyle=authoryear]{elegantbook} 
+\end{lstlisting}
+
+\section{Preface}
+
+If you want to add a preface before the first chapter with the number of chapter unchanged, please add the preface in the following way:
+\begin{lstlisting}
+\chapter*{Introduction}
+\markboth{Introduction}{Introduction}
+The content of introduction.
+\end{lstlisting}
+
+\section{Content Option and Depth}
+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 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:
+\begin{lstlisting}
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+\end{lstlisting}
+And you will get:
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+
+You can change the title of this environment by modifying the optional argument of this environment:
+\begin{lstlisting}
+\begin{introduction}[Brief Introduction]
+...
+\end{introduction}
+\end{lstlisting}
+
+%\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}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+\end{problemset}
+\end{lstlisting}
+And you will get:
+\begin{problemset}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+  \item math equation test:
+  \begin{equation}
+  a^2+b^2=c_{2_{i}} (1,2) [1,23]
+  \end{equation}
+\end{problemset}
+\begin{remark}
+If you want to customize the title of \lstinline{problemset}, please change the optional argument like in introduction environment. In this version the \lstinline{problemset} environment automatically appears in the table of contents but not in the header or footer(to be fixed).
+\end{remark}
+
+\begin{solution}
+  If you want to customize the title of \lstinline{problemset}, please change the optional argument like in introduction environment. In this version the \lstinline{problemset} environment automatically appears in the table of contents but not in the header or footer(to be fixed).
+\end{solution}
+
+\section{Margin Notes}
+In 3.08, we introduced \lstinline{marginpar=margintrue} and \lstinline{\elegantpar} (Beta) with piles of bugs. Hence we decide to remove them in 3.09 and will suspend the options till revolutionary optimization. Sorry for all the bugs! However, we retain the option \lstinline{marginpar} for users to get margin motes by activating \lstinline{marginpar=margintrue} and using \lstinline{\marginpar} or \lstinline{marginnote} packages.
+
+\begin{remark}
+Note that text and equation are both available in the margin notes.
+\begin{lstlisting}
+% text
+\marginpar{margin paragraph text}
+
+% equation
+\marginpar{
+\begin{equation}
+  a^2 + b^2 = c^2
+\end{equation}
+}
+\end{lstlisting}
+
+For tables and figures, note that floating environment is not allowed. You have to use \lstinline{includegraphics} or \lstinline{table} and use \lstinline{\captionof} to name it. To get centralized figures or tables, use \lstinline{\centerline} or \lstinline{center}. To learn more, please refer to \href{https://tex.stackexchange.com/questions/5583/caption-of-figure-in-marginpar-and-caption-of-wrapfigure-in-margin}{Caption of Figure in Marginpar}.
+
+\begin{lstlisting}
+% graph with centerline command
+\marginpar{
+  \centerline{
+    \includegraphics[width=0.2\textwidth]{logo.png}
+  }
+  \captionof{figure}{your figure caption}
+}
+
+% graph with center environment
+\marginpar{
+  \begin{center}
+    \includegraphics[width=0.2\textwidth]{logo.png}
+    \captionof{figure}{your figure caption}
+  \end{center}
+}
+\end{lstlisting}
+
+\end{remark}
+
+
+
+\chapter{ElegantBook Writing Sample}
+
+\begin{introduction}
+\item Theorem Class Envrionments
+\item Cross Reference
+\item Math Environments
+\item List Environments
+\item Logo and Base 
+\item $a^2+b^2=c^2$
+\end{introduction}
+
+
+\lipsum[1]
+% source: https://www.maths.tcd.ie/~dwilkins/LaTeXPrimer/Theorems.html
+
+\section{Writing Sample}
+
+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 $Hx = \{ hx : h \in H \}$ $\hbar$
+\end{definition}
+
+\begin{note}
+Note that a subgroup~$H$ of a group $G$ is itself a left coset of $H$ in $G$.
+\end{note}
+
+\lipsum[2]
+
+\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}
+
+\ref{thm:lg}
+\lipsum[3]
+
+   
+\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. 
+\end{proof}
+
+\begin{figure}[htbp]
+  \centering
+  \includegraphics[width=0.6\textwidth]{scatter.jpg}
+  \caption{Matplotlib: Scatter Plot Example\label{fig:scatter}}
+\end{figure}
+
+Regression analysis is a powerful statistical method that allows you to examine the relationship between two or more variables of interest. While there are many types of regression analysis, at their core they all examine the influence of one or more independent variables on a dependent variable. The process of performing a regression allows you to confidently determine which factors matter most, which factors can be ignored, and how these factors influence each other.
+
+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
+  \centering
+  \caption{Auto MPG and Price \label{tab:reg}}
+    \begin{tabular}{lcc}
+    \toprule
+                    &       (1)         &        (2)      \\
+    \midrule
+    mpg             &    -238.90***     &      -49.51     \\
+                    &     (53.08)       &      (86.16)    \\
+    weight          &                   &      1.75***    \\
+                    &                   &      (0.641)    \\
+    constant        &     11,253***     &       1,946     \\
+                    &     (1,171)       &      (3,597)   \\
+    obs             &        74         &         74     \\
+    $R^2$           &      0.220        &       0.293    \\
+    \bottomrule
+    \multicolumn{3}{l}{\scriptsize Standard errors in parentheses} \\
+    \multicolumn{3}{l}{\scriptsize *** p<0.01, ** p<0.05, * p<0.1} \\
+    \end{tabular}%
+\end{table}%
+
+\lipsum[1-2]
+
+\begin{itemize}
+  \item Routing and resource discovery;
+       \begin{itemize} 
+             \item Language Models
+            \item Vector Space Models
+         \end{itemize}
+  \item Resilient and scalable computer networks;
+  \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 slope of the line $5x - 5y = 7$.
+\end{problemset}
+
+
+\chapter{FAQ}
+We list some FAQs for users to refer to:
+\begin{enumerate}
+  \item \question{Why option numbers for natbib fail to take effect in v3.07?}
+  In v3.07, when \lstinline{gbt7714} is introduced, option \lstinline{authoryear} is incompatible with \lstinline{natbib}. In v3.08 and 3.09, \lstinline{numbers}, \lstinline{numbers}, \lstinline{super} and \lstinline{authoryear} are introduced.
+  \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 2021.
+  \item \question{Which editor should I choose?}
+  You can use \TeX{} Live 2021 built-in \TeX works or \TeX Studio. You may refer to \href{https://github.com/EthanDeng/texworks-autocomplete}{\TeX{}works autocomplete}. \TeX{} Live 2021 + \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}.
+  \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.
+  \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}, 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 17 releases on GitHub since uploaded.
+
+\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}.
+  \item \textbf{! Warnings}: Due to this `urgent' fonts bug and TOC modification, the multilingual option may cause some unexpected errors, you can report in this \href{https://github.com/ElegantLaTeX/ElegantBook/issues/170}{issue}, I will fix it after the releases of \TeX{} Live 2022.
+\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}
+
+\begin{change}
+  \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{change}
+
+\datechange{2019/08/18}{release of v3.09}
+
+\begin{change}
+  \item Remove \lstinline{\elegantpar} temporary and remind users to use \lstinline{\marginnote} and \lstinline{\marginpar} instead.
+  \item Use \lstinline{esint} to display integral operator.
+  \item Add new command \lstinline{toc}, with options  \lstinline{onecol} and \lstinline{twocol}.
+  \item Add new option \lstinline{cite} \lstinline{super} for superscript-displayed citation.
+  \item Revise \lstinline{problemset}.
+\end{change}
+
+\nocite{en2,en3}
+
+\printbibliography[heading=bibintoc, title=\ebibname]
+
+\appendix
+% \renewcommand\chaptername{\eappendix \thechapter}
+
+\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.
+
+\section{Summation Operator and Description Statistics}
+
+\textbf{Summation Operator} is an abbreviation used to express the summation of numbers, it plays an important role in statistics and econometrics analysis. If $\{x_i: i=1, 2, \ldots, n\}$ is a sequence of $n$ numbers, the summation of the $n$ numbers is:
+
+\begin{equation}
+\sum_{i=1}^n x_i \equiv x_1 + x_2 +\cdots + x_n
+\end{equation}
+
+
+\end{document}

guide.tex

@@ -1,266 +0,0 @@
-%!TEX program = xelatex
-\documentclass[mathpazo,titlestyle=hang,11pt]{elegantbook}
-
-\author{ddswhu \& LiamHuang0205}
-\email{ddswhu@outlook.com}
-
-\zhtitle{优美的\LaTeX{} 书籍}
-\zhend{模板}
-\entitle{Elegant\LaTeX{} Book}
-\enend{Template}
-\version{2.30}
-\myquote{Victory won\rq t come to us unless we go to it.}
-\logo{logo.pdf}
-\cover{cover.pdf}
-
-%green color
-   \definecolor{main1}{RGB}{0,120,2}
-   \definecolor{seco1}{RGB}{230,90,7}
-   \definecolor{thid1}{RGB}{0,160,152}
-%cyan color
-   \definecolor{main2}{RGB}{0,175,152}
-   \definecolor{seco2}{RGB}{239,126,30}
-   \definecolor{thid2}{RGB}{120,8,13}
-%blue color
-   \definecolor{main3}{RGB}{20,50,104}
-   \definecolor{seco3}{RGB}{180,50,131}
-   \definecolor{thid3}{RGB}{7,127,128}
-
-\usepackage{makecell}
-\usepackage{lipsum}
-\usepackage{texnames}
-
-
-\begin{document}
-\maketitle
-\tableofcontents
-\mainmatter
-\chapter{ElegantBook 模板的由来}
-
-只有当自己想去做一件事的时候才能把事情做好！
-
-
-\section{ElegantNote 的前世今生}
-
-写 ElegantNote 模板的初衷是为了简化我在写笔记中的工作，因为我不会写类文件和包文件，所以，最当初是想拜托小L做出一个华丽，清爽的 \LaTeX{} 模板，最好是类文件，而且因为这样可以简化导言区复杂的内容。后来，和小L一拍即合，遂开始一起做Elegant\LaTeX{}的设计。
-
-在学校的时候，搞定了定理环境样式的代码。因为不想重复 China\TeX{} 那个经典的页眉页脚，我找到了计量书上的一个图案，小L拿 Ti\emph{k}Z 一点一点把那个画出来了，不过我最后还是用的截取的方式得到的图案。慢慢地，我们把初步的样子做出来了。
-
-2013年的暑假开始后，我对那个初步的模板做了一点改动，然后用它写了Dynamic Programing 的笔记，并且，在写的过程中，对模板加了封面，也就是模板现在的封面（logo 在Version 2.00中已经改了）。至此，模板的大致样子终于出来了，不过当时也在写笔记的过程中知道了某些不足，比如
-\begin{enumerate}
-\item 定理类的环境在我们这个模板中不能浮动，也不能跨页，在Version 2.00 版本中已经添加。
-\item 某些环境不足，比如例子、假设、性质、结论等环境，在1.00版本中已经增加了这几个环境，在2.00版本中，环境设置更加全面。
-\item 一些我们不可预知的错误将会不期而遇。
-\item 一些我们目前没有需求，但是可以继续改进的地方，比如表格样式，比如抄录样式等。
-\end{enumerate}
-
-写完那个笔记之后越发让我对 Elegant\LaTeX{} 模板的制作更有激情，在和小L相互讨论的几天里，我们终于得到了1.00 版本的 ElegantNote 模板。
-
-\section{ElegantBook 的诞生}
-
-在实际应用中，我们发现了一个比较重要的问题，因为在一般的笔记中，定义、定理经常一起出现，和课本区别比较大的是，通常是一堆定义之后，出现一堆性质或者定理。如果出现这种情况，使用 ElegantNote 模板会导致分块很严重，影响排版质量和美观。思前想后，我们决定将 ElegantNote 模板更新为 ElegantBook 模板，并在未来重新设计一个简洁版本的 ElegantNote。 至此ElegantBook 才横空出世，由于更名原因，ElegantBook 1.00 版本也即原来的 ElegantNote， 而ElegantBook 2.00 为目前的正式版本。
-
-\section{一张白纸折腾出的一个模板}
-
-我以前从未写过类文件，所以，写这个模板的过程必然是折腾的过程，在写模板的过程中，最主要参考了《写给\LaTeXe{} 类与宏包的作者》\cite{packagewriter}、moderncv.cls 文件、\href{http://aff.whu.edu.cn/huangzh/}{武汉大学黄正华老师的论文模板}、《\LaTeXe{} 完全学习手册》\cite{complete}、{\itshape The Not So Short Introduction to \LaTeXe{}}\cite{oetiker2010not}以及各大\LaTeX{} 疑问解答网站，在此为无私奉献的组织和个人表示感谢！
-
-{\color{thid}忍不住插个图！}
-
-\begin{figure}[!hbtp]
-\includegraphics[width=0.8\textwidth]{happy.jpg}
-\caption{Happiness,we have it!\label{figur:happy}}
-\end{figure}
-
-\chapter{ElegantBook 开服说明}
-\section{关于我们}
- 我们目前都是学生，接触 \LaTeX{} 的时间也不是很长，因此，对于此模板的错误还请多多包涵！ 目前，模板的拓展性或者可移植性有待完善，所以，我们强烈建议用户不要大幅修改模板文件，我们的初衷是提供一套模板，让初学者能够使用一些比较美观，优雅的模板。如果在使用过程中，想修改一些简单的东西需要帮忙，请联系我们，我们的邮箱是：\href{elegantlatex2e@gmail.com}{elegantlatex2e@gmail.com}。我们将竭尽全力提供帮助！
-
-值此版本发行之际，我们 Elegant\LaTeX{} 项目组向大家重新介绍一下我们的工作，我们的主页是 \href{http://elegantlatex.org}{http://elegantlatex.org}，我们这个项目致力于打造一系列美观、优雅、简便的模板方便使用者记录学习历史。其中目前在实施或者在规划中的子项目有 书籍模板ElegantBook、笔记模板ElegantNote、幻灯片模板 ElegantSlide。这些子项目的名词是一体的，请在使用这些名词的时候不要将其断开（如 Elegant Note是不正确的写法）。并且，Elegant\LaTeX{}  Book 指的即是 ElegantBook。
-
-如果您在使用此模板，方便的话，是否可以把您使用此模板制作的成品发一份给我们，谢谢！
-
-\section{关于字体}
-
-基于本模板追求视觉上的美观的角度，强烈建议使用者安装./fonts/文件夹下的字体。出于版权的考虑，务必不能将此模板用于涉及盈利目的的商业行为，否则，后果自负，本模板带的字体仅供学习使用，如果您喜欢某种字体，请自行购买正版。本文主要使用的字体如下
-
-\begin{itemize}
-\itemsep=3pt
-\parskip=0pt
-\item Adobe Garamond Pro
-\item 方正苏新诗柳楷简体
-\item 方正启体简体
-\end{itemize}
-
-\begin{note}
-虽然我们模板更新到了 2.30 了（主要是字体删除，交叉引用的紧急修复），但是使用文档部分并没有更新（仍然是 2.00），在使用过程中，请尽量参考文档说明，如果有问题，可以联系我们。
-
-如果系统内安装了Adobe 字体，大家可以把模板中使用到的黑体，楷体，宋体等字替换成 Adobe 字体，这样可以达到最佳效果。
-\end{note}
-
-\section{文档说明}
-\subsection{编译方式}
-本模板基于book文类，所以book的选项对于本模板也是有效的。但是，只支持 \XeLaTeX{}，编码为 UTF-8，推荐使用 \TeX{}live编译。作者编写环境为Win8.1(64bit)+\TeX{}live 2013，由于使用了参考文献，所以，编译顺序为\XeLaTeX->\BibTeX->\XeLaTeX->\XeLaTeX。
-
-本文特殊选项设置共有3类，分为{\color{main}颜色} 、{\color{main} 数学字体 }以及{\color{main} 章标题显示风格}。
-
-\subsection{选项设置}
-第一类为{\color{main}颜色}主题设置，内置 3 组颜色主题，分别为 \verb|green|（默认），\verb|cyan|，\verb|blue|，另外还有一个自定义的选项 \verb|nocolor|，用户\textbf{必须}在使用模板的时候选择某个颜色主题或选择 \verb|nocolor|选项。调用颜色主题 \verb|green| 的方法为\verb|\documentclass[green]{elegantbook}|或者使用\verb|\documentclass[color=green]{elegantbook}|。需要改变颜色的话请选择 \verb|nocolor|选项或者使用 \verb|color=none|，然后在导言区定义main、seco、thid颜色，具体的方法如下：
-\begin{verbatim}
-\definecolor{main}{RGB}{70,70,70}    %定义main颜色值
-\definecolor{seco}{RGB}{115,45,2}    %定义seco颜色值
-\definecolor{thid}{RGB}{0,80,80}     %定义thid颜色值
-\end{verbatim}
-
-第二类为{\color{main}数学字体}设置，有两个可选项，分别是 mathpazo（默认） 和 mtpro2 字体，调用mathpazo 字体使用 \verb|\documentclass[mathpazo]{elegantbook}|，调用 mtpro2 字体时需要把 \verb|mathpazo|换成 \verb|mtpro|，mathpazo 不需要用户自己安装字体，mtpro2 的字体需要自己安装。
-
-\begin{table}[htp]
-\centering
-\begin{tabular}{ccccc}
-\toprule
-	  & green & cyan & blue & 主要使用的环境\\
-\midrule
-main & \makecell{{\color{main1}\rule{1cm}{1cm}}}& \makecell{{\color{main2}\rule{1cm}{1cm}}}&\makecell{ {\color{main3}\rule{1cm}{1cm}}}& newthem \ newlemma \ newcorol\\
-
-seco &\makecell{ {\color{seco1}\rule{1cm}{1cm}}}& \makecell{{\color{seco2}\rule{1cm}{1cm}}}&\makecell{ {\color{seco3}\rule{1cm}{1cm}}}&newdef\\
-
-thid &\makecell{ {\color{thid1}\rule{1cm}{1cm}}}& \makecell{{\color{thid2}\rule{1cm}{1cm}}}&\makecell{ {\color{thid3}\rule{1cm}{1cm}}}&newprop\\
-\bottomrule
-\end{tabular}
-\caption{ElegantBook 模板中的三套颜色主题\label{tab:color thm}}
-\end{table}
-
-第三类为{\color{main} 章标题显示风格}，包含 \verb|hang|（默认）与 \verb|display|两种风格，区别在于章标题单行显示（\verb|hang|）与双行显示（\verb|display|），本说明使用了 \verb|hang|。调用方式为 \verb|\documentclass[hang]{elegantbook}|或者 \verb|\documentclass[titlestyle=hang]{elegantbook}|。
-
-综合起来，同时调用三个选项使用 \verb|\documentclass[color=X,Y,titlestyle=Z]{elegantbook}|。其中 \verb|X| 可以选择 \verb|green|,\verb|cyan|,\verb|blue|,\verb|none|；\verb|Y| 可以选择 \verb|mathpazo|或者 \verb|mtpro|；\verb|Z|可以选择 \verb|hang| 或者 \verb|display|。
-
-\subsection{数学环境简介}
-在我们这个模板中，定义了三大类环境
-\begin{enumerate}
-\item 定理类环境，包含标题和内容两部分。根据格式的不同分为3种
-\begin{itemize}
-\item {\color{main} newthem、newlemma、newcorol} 环境，颜色为主颜色main，三者编号均以章节为单位；
-\item {\color{main} newdef} 环境，含有一个可选项，编号以章节为单位，颜色为seco；
-\item {\color{main} newprop} 环境，含有一个可选项，编号以章节为单位，颜色为thid。
-\end{itemize}
-\item 证明类环境，有  {\color{main} newproof、note、remark、solution} 环境，特点是，有引导符和引导词，并且 newproof、solution 环境有结束标志。
-\item 结论类环境，有 {\color{main}  conclusion、assumption、property} 环境，三者均以粗体的引导词为开头，和普通段落格式一致。
-\item 示例类环境--- {\color{main} example、exercise}环境，编号以章节为单位，其中exercise环境有引导符。
-\item 自定义环境--- {\color{main} custom}，带一个必选参数，格式与conclusion 环境很类似。
-\end{enumerate}
-
-\subsection{可编辑的字段}
-在模板中，可以编辑的字段分别为作者\verb|\author|、\verb|\email|、\verb|\zhtitle|、\verb|\zhend|、\verb|\entitle|、\verb|\enend|、\verb|\version|。并且，可以根据自己的喜好把封面水印效果的\verb|cover.pdf|替换掉，以及封面中用到的\verb|logo.pdf|。
-
-\chapter{ElegantBook 写作示例}
-
-\section{灵魂不随便出卖，代码也不随便瞎写}
-\lipsum[3]
-考虑如下的随机动态规划问题
-\begin{align*}
-&\max(\min)\quad \mathbb{E}\int_{t_0}^{t_1}f(t,x,u)\,dt\\
-&\quad\mbox{s.t.} \quad dx=g(t,x,u)dt+\sigma(t,x,u)dz\\
-&\quad \hspace{2.em} k(0)=k_0\;\text{given}
-\end{align*}
-
-where $z$ is stochastic process or white noise or wiener process.
-
-\begin{newdef}[Wiener Process]
-If $z$ is wiener process, then for any partition $t_0,t_1,t_2,\ldots$ of time interval, the random variables $z(t_1)-z(t_0),z(t_2)-z(t_1),\ldots$ are independently and normally distributed with zero means and variance $t_1-t_0,t_2-t_1,\ldots$
-\end{newdef}
-
-\lipsum[5]
-
-\begin{example}
-$E$ and $F$ be two events such that $\mbf{P}(E)=\mbf{P}(F)=1/2$, and $\mbf{P}(E\cap F)=1/3$, let $\mathscr{F}=\sigma(Y)$,  $X$ and $Y$ be the indicate function of $E$ and $F$ respectively. How to compute $\mathbb{E}[ X\mid \mathscr{F} ]$?
-\end{example}
-\lipsum[4]
-\begin{exercise}
-let $S=l^\infty=\big\{(x_n)\mid \exists\, M \text{ such that } \forall n, |x_n|\leq M,x_n\in \mathbb{R}\big\}$, $\rho_{\infty}(x,y)=\sup\limits_{n\geq 1}|x_n-y_n|$, show that $\big(l^\infty,\rho_{\infty}\big)$ is complete.
-\end{exercise}
-
-\begin{newthem}[勾股定理]\label{thm:31}
-勾股定理的数学表达（Expression）为
-\[a^2+b^2=c^2\]
-其中$a,b$为直角三角形的两条直角边长，$c$为直角三角形斜边长。
-\end{newthem}
-
-\begin{note}
-在本模板中，引理（lemma），推论（corollary ）的样式和定理的样式一致，包括颜色，仅仅只有计数器的设置不一样。在这个例稿中，我们将不给出引理推论的例子。
-\end{note}
-
-
-\lipsum[4]
-
-\begin{newprop}[最优性原理]
-如果$u^*$在$[s,T]$上为最优解，则$u^*$在$[s,T]$任意子区间都是最优解，假设区间为$[t_0,t_1]$的最优解为$u^*$，则$u(t_0)=u^{*}(t_0)$，即初始条件必须还是在$u^*$上。
-\end{newprop}
-
-\lipsum[5-6]
-\begin{newcorol}
-假设$V(\cdot,\cdot)$为值函数，则跟据最大值原理~\ref{thm:31}，有如下推论
-\[
-V(k,z)=\max\Big\{u\big(zf(k)-y\big)+\beta \mathbb{E}V(y,z^\prime)\Big\}
-\]
-\end{newcorol}
-
-\begin{newproof}
-因为 $y^*=\alpha\beta z k^\alpha$，$V(k,z)=\alpha/1-\alpha\beta\ln k_0+1/1-\alpha\beta \ln z_0+\Delta$。
-\begin{align*}
-\text{右边}&=\Big\{u\big(zf(k)-y\big)+\beta \mathbb{E}V(y,z^\prime)\Big\}\\
-&=\ln(zk^\alpha-\alpha\beta zk^\alpha)+\beta\mathbb{E}\Big[\frac{\alpha}{1-\alpha\beta}\ln y+\frac{1}{1-\alpha\beta}\ln z^\prime+\Delta\Big]\\
-&=\ln(1-\alpha\beta)zk^\alpha+\beta\Big\{\mathbb{E}\big[\frac{\alpha}{1-\alpha\beta}\ln \alpha\beta z k^\alpha\big]+\frac{1}{1-\alpha\beta}\mathbb{E}[\ln z^\prime]+\Delta\Big\}
-\end{align*}
-利用$\mathbb{E}[\ln z^\prime]=0$，并将对数展开得
-\begin{align*}
-\text{右边}&=\ln (1-\alpha\beta)+\ln z+\alpha\ln k+\frac{\alpha\beta}{1-\alpha\beta}\big[\ln \alpha\beta+\ln z+\alpha\ln k\big]+\frac{\beta}{1-\alpha\beta}\mu+\beta \Delta\\
-&=\frac{\alpha}{1-\alpha\beta}\ln k+\frac{1}{1-\alpha\beta}\ln z+\Delta
-\end{align*}
-所以$\text{左边}=\text{右边}$，证毕。
-\end{newproof}
-
-
-
-\begin{property}
-Properties of Cauchy Sequence
-\begin{enumerate}\parskip=0pt \itemsep=0pt
-\item $\{x_k\}$ is cauchy sequence then $\{x_k^i\}$ is cauchy sequence.
-\item $x_k\in \mathbb{R}^n$, $\rho(x,y)$ is Euclidean, then cauchy is equivalent to convergent, $(\mathbb{R}^n,\rho)$ metric space is complete.
-\end{enumerate}
-\end{property}
-
-
-\lipsum[7]
-
-\begin{custom}{Application}
-This is one example of the custom environment, the key word is given by the option of custom environment.
-\end{custom}
-
-
-\lipsum[6]
-\begin{newdef}[Contraction mapping]
-$(S,\rho)$ is the metric space, $T: S\to S$, If there exists $\alpha\in(0,1)$ such that for any $x$ and $y\in S$, the distance
-\begin{equation}
-\rho(Tx,Ty)\leq \alpha\rho(x,y)
-\end{equation}
-Then $T$ is a {\color{main} contraction mapping}.
-\end{newdef}
-
-\begin{remark}
-\begin{enumerate}
-\parskip=0pt \itemsep=0pt
-\item $T:S\to S$, where $S$ is a metric space, if  for any $x,y\in S$, $\rho(Tx,Ty)<\rho(x,y)$ is not contraction mapping.
-\item Contraction mapping is continuous map.
-\end{enumerate}
-\end{remark}
-
-
-\begin{conclusion}
-看到一则小幽默，是这样说的：{\color{main} 别人都关心你飞的有多高，只有我关心你的翅膀好不好吃！}说多了都是泪啊！
-\end{conclusion}
-
-
-\bibliographystyle{ieeetr}
-\bibliography{reference}
-\addcontentsline{toc}{chapter}{参考文献}
-
-\end{document}

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