答案1
这可能是一个开始。
\documentclass{article}
\usepackage{tikzpagenodes}
\usetikzlibrary{calc}
\usepackage[explicit]{titlesec}
\definecolor{myblue}{RGB}{91,134,199}
\titleformat{\section}{}{}{0em}{%
\tikz[baseline={(sec-\number\value{section}.base)},myblue,remember picture]{
\node(sec-\number\value{section}) {\LARGE\bfseries\sffamily\MakeUppercase{#1}};
\fill[overlay] let \p1=($(sec-\number\value{section}.north)-(sec-\number\value{section}.south)$)
in ([yshift=3pt]sec-\number\value{section}.south east) --
([yshift=3pt]sec-\number\value{section}.south-|current page text area.east)
arc[start angle=0,end angle=90,radius=\y1-6pt] -| cycle;
}}
\begin{document}
\section{Introduction}
Pft pft.
\section{Another section}
Pft pft pft.
\end{document}