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 # BeamerTheme
-define a simple beamer theme
+
+## Introduction
+
+This project include two themes, long and short version. When you are making a long slide, a sidebar with table of content and the current section you are talking about is necessary. Then, you can write your file based on `template_long.tex`, otherwise `template_short.tex`.
+
+`.pdf` files and demos below show the baisc style of this beamer theme. 
+
+## Usage
+
+You can just input one of the template files and define colors you like to inherit this theme. Just like what `example_*.tex`s do.
+
+For example
+
+```
+\documentclass[aspectratio=169]{beamer}
+
+\input{template_long.tex}
+
+\colorlet{main}{green!50!black}
+
+%-------------------main body-------------------------%
+\author{Your Name}
+\title{Presentation Title}
+\begin{document}
+
+
+\end{document}
+```
+
+(Hint: Make sure that template_long.tex and your tex file is in the same folder.)
+
+Of course, you cna modify the theme based on the two template files to extend new styles. For each element you want to modify, just google it! There are a lot of answers to help you.
+
+## Demos
+
+![long green version](long_green.jpg)
+
+![long red version](long_red.jpg)
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diff --git a/example_long.tex b/example_long.tex
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+\documentclass[aspectratio=169]{beamer}
+
+\input{template_long.tex}
+
+\colorlet{main}{green!50!black}
+% \colorlet{main}{red!50!black}
+% \colorlet{main}{purple}
+
+%-------------------main body-------------------------%
+
+\author{Your Name}
+\title{Presentation Title}
+\date{January 1, 2018}
+
+\begin{document}
+
+\frame[plain]{\titlepage}
+
+\begin{frame}
+\frametitle{Outline}
+\tableofcontents
+\end{frame}
+
+\section{Page Title}
+
+\frame{\frametitle{Outline}\tableofcontents[currentsection]}
+
+\begin{frame}
+\frametitle{Page Title}
+
+TeX - LaTeX Stack Exchange is a question and answer site for users of TeX, LaTeX, ConTeXt, and related typesetting systems.
+
+\vspace{0.4cm}
+
+unordered list below
+
+\begin{itemize}
+\item The first item
+\item The second item
+\item The third item
+\item The fourth item
+\end{itemize}
+
+\end{frame}
+
+\section{Display Theorem}
+
+\frame{\frametitle{Outline}\tableofcontents[currentsection]}
+
+\subsection{first subsection}
+
+\subsection{second subsection}
+
+\begin{frame}
+  \frametitle{Display Theorem}
+  \begin{theorem}
+    $1 + 2 = 3$
+  \end{theorem}
+  \begin{proof}
+    $$1 + 1 = 2$$
+    $$1 + 1 + 1 = 3$$
+  \end{proof}
+\end{frame}
+
+\section{Sample frame title}
+
+\frame{\frametitle{Outline}\tableofcontents[currentsection]}
+
+\begin{frame}
+\frametitle{Sample frame title}
+This is a text in second frame.
+For the sake of showing an example.
+
+\begin{itemize}
+ \item Text visible on slide 1
+ \item Text visible on slide 2
+ \item Text visible on slide 3
+\end{itemize}
+
+\vspace{0.3cm}
+
+another example
+
+\begin{itemize}\itemsep0em
+ \item Text visible on slide 1
+ \item Text visible on slide 2
+ \item Text visible on slide 3
+\end{itemize}
+\end{frame}
+
+\begin{frame}
+  \begin{proof}
+    $$
+ \frac{1}{\displaystyle 1+
+   \frac{1}{\displaystyle 2+
+   \frac{1}{\displaystyle 3+x}}} +
+ \frac{1}{1+\frac{1}{2+\frac{1}{3+x}}}
+$$
+$$\int_0^\infty e^{-x^2} dx=\frac{\sqrt{\pi}}{2}$$
+\begin{equation} x=y+3 \label{eq:xdef}
+\end{equation}
+In equation (\ref{eq:xdef}) we saw $\dots$
+  \end{proof}
+\end{frame}
+
+
+\end{document} 
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diff --git a/template_long.tex b/template_long.tex
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+% This file contains some settings , it need to be input by your tex file.
+
+\usepackage[english]{babel}
+% add sidebar on the right
+\useoutertheme[width=3\baselineskip,right]{sidebar}
+% TOC(table of content) using ordered list 
+\setbeamertemplate{section in toc}[sections numbered]
+% unordered list using solid point
+\setbeamertemplate{itemize item}{$\bullet$}
+% set frame title for each page
+\setbeamertemplate{frametitle}
+  {\vspace{-0.5cm}
+   \insertframetitle
+   \vspace{-0.5cm}}
+% delete original navigation
+\setbeamertemplate{navigation symbols}{}
+% set footline
+\makeatother
+\setbeamertemplate{footline}
+{
+  \leavevmode%
+  \hbox{%
+  \begin{beamercolorbox}[wd=.4\paperwidth,ht=2.25ex,dp=1ex,center]{author in head/foot}%
+    \usebeamerfont{author in head/foot}\insertshortauthor
+  \end{beamercolorbox}
+
+  \begin{beamercolorbox}[wd=.6\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
+    \usebeamerfont{title in head/foot}\insertshorttitle\hspace*{13em}
+    \insertframenumber{} / \inserttotalframenumber\hspace*{0ex}
+  \end{beamercolorbox}}
+
+  \vskip0pt%
+}
+\makeatletter
+
+
+% define color
+%\definecolor{alizarin}{rgb}{0.82, 0.1, 0.26} % a kind of red
+%\definecolor{DarkFern}{HTML}{407428} % a kind of green
+%\colorlet{main}{DarkFern!100!white} % first setting way(with color newly defined)
+%\colorlet{main}{red!70!black} % second setting way(with internal color by setting gradient)
+\definecolor{bistre}{rgb}{0.24, 0.17, 0.12} % a kind of black
+\definecolor{mygrey}{rgb}{0.52, 0.52, 0.51} % a kind of grey
+\colorlet{text}{bistre!100!white} % from now on, `text` implies the color defined
+
+% set colors to elements, fg is the color itself, bg is the background color, !num! implies gradient
+\setbeamercolor{title}{fg=main}
+\setbeamercolor{frametitle}{fg=main}
+\setbeamercolor{section in toc}{fg=text}
+\setbeamercolor{normal text}{fg=text}
+\setbeamercolor{block title}{fg=main,bg=mygrey!14!white}
+\setbeamercolor{block body}{fg=black,bg=mygrey!10!white}
+\setbeamercolor{qed symbol}{fg=main} % frame after proof
+\setbeamercolor{math text}{fg=black}
+% footline color
+\setbeamercolor{author in head/foot}{fg=black, bg=mygrey!5!white}
+\setbeamercolor{title in head/foot}{fg=black, bg=mygrey!5!white}
+\setbeamercolor{structure}{fg=main, bg=mygrey!10!white} % 设置sidebar颜色
+
+% margin left and right, and fontsize of sidebar
+\def\swidth{2.3cm}
+\setbeamersize{sidebar width right=\swidth}
+\setbeamersize{sidebar width left=\swidth}
+\setbeamerfont{title in sidebar}{size=\scriptsize}
+\setbeamerfont{section in sidebar}{size=\tiny}