如何在校样中添加右侧栏

Question

当我使用mdframed正确的栏目是证明双线：

    \documentclass{book}
\usepackage{xpatch,amsthm,xcolor}
\usepackage{color}
\usepackage[framemethod=tikz]{mdframed}

\usepackage{polyglossia}
\usepackage[left=2cm,right=2cm,top=2cm,bottom=2cm]{geometry}
%select languages & fonts ==================================
\makeatletter
 \xpatchcmd{\@thm}{\fontseries\mddefault\upshape}{}{}{} % same font 
\xpatchcmd{\proof}{\itshape}{\bfseries\proofnameformat}{}{}

\newcommand{\proofnameformat}{}
\makeatother
\setdefaultlanguage[calendar=gregorian,locale=algeria]{arabic}
\setotherlanguage{english}
\newfontfamily\arabicfont[Script=Arabic,Scale=1.3]{Amiri}
\mdfdefinestyle{my}{
 hidealllines=true,
  rightline=true,
  innerleftmargin=10pt,
  innerrightmargin=10pt,
  innertopmargin=0pt,
 % middlelinewidth=1pt,
}
\surroundwithmdframed[style=my]{proof}% use the new theorem style
% declare a new theorem style
\newtheoremstyle{mystyle}%
{5pt}% Space above
{5pt}% Space below 
{\color{black}}% Body font\itshape
{}% Indent amount
{\bfseries\color{blue}}% Theorem head font
{.}% Punctuation after theorem head
{.5em}% Space after theorem head 
{}% Theorem head spec (can be left empty, meaning ‘normal’)

\theoremstyle{mystyle}
\newtheorem{thm}{مبرهنة}[section]
\newtheorem{prop}{خاصية}[section]
\newtheorem{exm}{مثال}
\newtheorem{rem}{ملاحظة}[section]
\begin{document}
\begin{thm}
$a$
عدد حقيقي موجب.\\
 نسمي الجذر التربيعي للعدد الحقيقي   العدد الحقيقي الموجب الذي مربعه يساوي  $ a $ ونرمزه إليه
  $ \sqrt{a}$.
\end{thm}
\begin{proof}
بلبل\\
يسي
\end{proof}
\end{document}