What package is used here to produce the beautiful summary?

Question

I have already finished writing a book and I would like to produce this kind of table of contents as a summary.

Answer 1

Here's the code fragment for the table of contents of the pas-math package, available on this page of the author's site.

\begin{tcolorbox}[toc]
\makeatletter
\@starttoc{toc}
\makeatother
\end{tcolorbox}