# How to create this section style?

I want to have a section style like in the below picture.

The size of corners should be flexible with the length of the section title.

• what you try so far? – Zarko Mar 26 '17 at 19:34

You can use tikz to draw the corners and titlesec to customize the format of headings:

\documentclass{article}
\usepackage{tikz}
\usepackage{titlesec}

\newcommand{\sectionformat}[1]{%
\begin{tikzpicture}[baseline=(title.base)]
\node (title) {\thesection\hspace{1em}#1};
\draw[double] (title.west) |- (title.south) (title.north) -| (title.east);
\end{tikzpicture}
}

% default values copied from titlesec documentation page 23
% parameters of \titleformat command are explained on page 4
\titleformat%
{\section}% <command> is the sectioning command to be redefined, i. e., \part, \chapter, \section, \subsection, \subsubsection, \paragraph or \subparagraph.
{\normalfont\Large\bfseries}% <format>
{}% <label> the number
{0em}% <sep> length. horizontal separation between label and title body
{\sectionformat}% code preceding the title body  (title body is taken as argument)

\usepackage{blindtext}
\begin{document}
\Blinddocument
\end{document}


Edit: Please note that long headings will not break automatically. If you add a [align=left] after the \node you can insert line breaks by hand with \\.