代码请复制出来,放在代码块里,这是尊重提供答案的用户。
\documentclass{article}
\usepackage{xcolor}
\usepackage{ctex}
\usepackage[explicit]{titlesec}
\titleformat{\section}
{\sffamily\Large\bfseries\color{red!70!black}}
{}
{0em}
{\colorbox{red!70!black!10}{\parbox{\dimexpr\textwidth-2\fboxsep\relax }{\textcolor{red!70!black}{\thesection\quad#1}}}}
\titleformat{name=\section, numberless}
{\sffamily\Large\bfseries\color{red!70!black}}
{}
{0em}
{\colorbox{red!70!black!10}{\parbox{\dimexpr\textwidth-2\fboxsep\relax }{\textcolor{red!70!black}{#1}}}}
\begin{document}
\section{the}
\begin{thebibliography}{99}
\bibitem{Tadmor2012} Tadmor~E. A review of numerical methods for nonlinear partial differential
equations \allowbreak[J]. Bull. Amer. Math. Soc., 2012, 49(4): 507- 554.
\end{thebibliography}
\end{document}