use custom fonts. seems good

.latexmkrc

@@ -1,5 +0,0 @@
-$pdf_mode = 1;              # 生成PDF
-$latex = 'xelatex %O %S';   # 用 xelatex 替代 latex
-$pdflatex = 'xelatex %O %S'; # 用 xelatex 替代 pdflatex
-$dvi_mode = 0;              # 禁用DVI输出
-$postscript_mode = 0;       # 禁用PS输出

beamerthemeSimple.sty

@@ -1,19 +1,13 @@
-% !TEX program = xelatex
-% !TEX TS-program = xelatex
-% fonts
-\RequirePackage[sfdefault]{FiraSans}
-\RequirePackage{FiraMono} 
-\renewcommand{\rmfamily}{\sffamily}
-\RequirePackage[fakebold]{firamath-otf}
-\RequirePackage{xeCJK}
-\setCJKmainfont{Source Han Sans SC}
-
-\RequirePackage[english]{babel}
+% Copyright 2018 by Zhibo Wang
+%
+% This file may be distributed and/or modified
+% under the LaTeX Project Public License
+\usepackage{libertine}
+\RequirePackage[chinese, provide=*]{babel}
 \RequirePackage{fancyhdr}        % header footer
-\RequirePackage[dvipsnames]{xcolor}
+\RequirePackage{xcolor}
 \RequirePackage{bookmark}
 \RequirePackage{hyperref}[colorlinks=true,urlcolor=Blue,citecolor=Green,linkcolor=BrickRed,unicode]
-\RequirePackage{natbib}
 \RequirePackage{graphicx} % Allows including images
 \RequirePackage{booktabs} % Allows the use of \toprule, \midrule and \bottomrule in tables
 % \RequirePackage{tikz}
@@ -29,7 +23,29 @@
 % \RequirePackage[utf8]{inputenc}
 % \RequirePackage{CJKutf8}
 % \def\zh#1{\begin{CJK}{UTF8}{gbsn}#1\end{CJK}}
-\RequirePackage{aliascnt}
+% \RequirePackage{aliascnt}
+\RequirePackage{ctex}
+\RequirePackage{fontspec}
+\RequirePackage{xeCJK}
+% infact italic and BoldItalic fonts are missing
+\setCJKmainfont{LXGWNeoZhiSong}[
+  Path=./fonts/,
+  Extension = .ttf,
+  UprightFont=*,
+  BoldFont=*,
+  ItalicFont=*,
+  BoldItalicFont=*
+]
+\setCJKsansfont{LXGWWenKai}[
+  Path=./fonts/,
+  Extension = .ttf,
+  UprightFont=*-Regular,
+  BoldFont=*-Bold,
+  ItalicFont=*-Regular,
+  BoldItalicFont=*-Regular,
+]
+\XeTeXlinebreaklocale "zh" 
+\XeTeXlinebreakskip = 0pt plus 1pt 
 
 % a color box
 \RequirePackage[breakable, theorems, skins]{tcolorbox}
@@ -131,7 +147,7 @@
 \setbeamercolor{alerted text}{fg=beamer@simple@color}
 \setbeamerfont{block title alerted}{series=\mdseries}
 \setbeamerfont{alerted text}{series=\bfseries\boldmath}
-\hypersetup{colorlinks=true,linkcolor=,citecolor=Green,urlcolor=oliver}
+\hypersetup{colorlinks,linkcolor=,urlcolor=oliver}
 % \usefonttheme[onlymath]{serif}
 \setbeamerfont{frametitle}{series=\bfseries\boldmath}
 \setbeamerfont{block title}{series=\bfseries\boldmath}
@@ -141,14 +157,15 @@
 % theorem env
 \setbeamertemplate{theorem begin}{%
 {
-  \vspace{5pt}%
+  \vspace{5pt}
   \usebeamerfont*{block title}%
-  \selectfont%
+  \selectfont
   \usebeamercolor[fg]{block title}%
-  \textbf{%
+  \textbf{
   \inserttheoremname
-  \inserttheoremnumber
+  % \inserttheoremnumber
   \ifx \inserttheoremaddition \empty \else\ [\inserttheoremaddition]\fi
+  \inserttheorempunctuation
   }
 }
 }
@@ -157,7 +174,7 @@
 \setbeamertemplate{proof begin}{%
 {\vspace{5pt}
 \usebeamercolor[fg]{block title}
-\textit{\textbf{Proof:}}}
+\textit{Proof.}}
 }
 \setbeamertemplate{proof end}{
 \qedhere

main.tex

@@ -1,6 +1,6 @@
 \documentclass{beamer}
 
-\title[template example]{Minimizing the Sum of Piecewise Linear Convex Functions}
+\title[中文测试]{Minimizing the Sum of Piecewise Linear Convex Functions - 这是很长很长很长很长的兼有中文和英文的标题}
 \date{\today}
 \author{丛宇}
 % \AtBeginSection[]{
@@ -17,13 +17,13 @@
     \titlepage
 \end{frame}
 
-\begin{frame}[plain]{Plan}
+\begin{frame}[plain]{计划}
     \tableofcontents
 \end{frame}
 
-\section{Problems \& Definitions}
-\begin{frame}{$\min \sum f_i(a_i\cdot x-b_i)$}
-\begin{problem}
+\section{Problems \& Definitions 问题定义}
+\begin{frame}{$\min \sum f_i(a_i\cdot x-b_i)$ 中文测试}
+\begin{problem} regular 中文 jjjfff
     Given $n$ piecewise linear convex functions $f_1,...,f_n:\R \to \R$ of total $m$ breakpoints, and $n$ linear functions $a_i\cdot x-b_i:\R^d\to \R$, find $\min_x \sum_i f_i(a_i\cdot x-b_i)$.
 \end{problem}
 \begin{figure}