\documentclass{article}
\usepackage[most]{tcolorbox}
%-----------
\usepackage{fontspec}
\usepackage{xltxtra}
\defaultfontfeatures{Mapping=tex-text}
\XeTeXlinebreaklocale "khm"
\XeTeXlinebreakskip = 0pt plus 1pt minus 1pt
%-----------------------
\setmainfont{Khmer OS Siemreap}
\newcommand{\NK}{\fontspec[Scale=1,Script=Khmer]{Neadaka}\selectfont}
%-----------------font
%
https://t.me/tk_type/31
%-------លេខខ្មែរ--និង អក្សរខ្មែរ--------------------------
\usepackage{titletoc}
\contentsmargin{1.5cm}
\usepackage{enumerate}
\usepackage{enumitem}
\makeatletter %khmer list
\def\@khmernum#1{\expandafter\@@khmernum\number#1\@nil}
\def\@@khmernum#1{%
\ifx#1\@nil
\else
\char\numexpr#1+"17E0\relax
\expandafter\@@khmernum\fi
}
\def\knum#1{\expandafter\@khmernum\csname c@#1\endcsname}
\def\khmernumeral#1{\@@khmernum#1\@nil}
\AddEnumerateCounter{\knum}{\@knum}{}
\makeatother
\makeatletter
\newcommand*{\kalph}[1]{%
\expandafter\@kalph\csname c@#1\endcsname%
}
\newcommand*{\@kalph}[1]{%
\ifcase#1\or ក\or ខ\or គ\or ឃ\or ង\or ច\or ឆ\or ជ\or ឈ\or ញ\or ដ\or ឋ\or ឌ%
\or ឍ\or ណ\or ត\or ថ\or ទ\or ធ\or ន\or ប\or ផ\or ព\or ភ\or ម\or យ\or រ\or ល%
\or វ\or ស\or ហ\or ឡ\or អ%
\else\@ctrerr\fi%
}
\AddEnumerateCounter{\kalph}{\@kalph}{}
\makeatother
%----------------------------------------------------ទំព័រលេខខ្មែរ---------------------------------------------------------------
\makeatletter
\def\@khmernum#1{\expandafter\@@khmernum\number#1\@nil}
\def\@@khmernum#1{%
\ifx#1\@nil
\else
\char\numexpr#1+"17E0\relax
\expandafter\@@khmernum\fi
}
%\def\khmercounter#1{\expandafter\@khmernum\csname c@#1\endcsname}
\renewcommand\@arabic{\@khmernum}% to reset number in \arabic to \khmernum
%---------------
\newtcolorbox{KP}[2]{title=#1,breakable,
,enhanced, before skip=2mm,after skip=3mm,
boxrule=0.4pt,left=5mm,right=2mm,top=.7cm,bottom=1mm,
colback=white,
colframe=#2!80!black,boxed title style={right=3pt, bottom=3pt,, overlay={
\draw[draw=#2, fill=#2!50!teal, line join=round]
(frame.south west) -- (frame.north west) -- (frame.north east) --
(frame.south east);
\draw[draw=#2!50, fill=#2!50!gray, line join=round]
(frame.south west) -- (frame.north west) -- (frame.north east) --
(frame.south east) -- ++(-.2, 0) -- ++(-.2, -4pt) --
++(-.2, 4pt);
} ,
},
sharp corners,rounded corners=southeast,arc is angular,arc=3mm,
underlay={%
\path[fill=#2!50!black] ([yshift=3mm]interior.south east)--++(-0.4,-0.1)--++(0.1,-0.2);
\path[draw=#2!80!black,shorten <=-0.05mm,shorten >=-0.05mm] ([yshift=3mm]interior.south east)--++(-0.4,-0.1)--++(0.1,-0.2);
},
colbacktitle=white,
attach boxed title to top left={xshift=8mm,yshift=-.4cm},
,drop fuzzy shadow=#2!80!black}
\begin{document}
\begin{KP}{\NK ទ្រឹស្តីបទទី ១.១១}{red}
content...
\end{KP}
\begin{KP}{\NK ចំណាំ}{blue}
លំហាត់
\begin{enumerate}[label=\NK\kalph*.]
\item
\item
\item
\item
\item
\item
\item
\end{enumerate}
\end{KP}
\begin{KP}{\NK លំហាត់សម្រាប់អនុវត្តន៍}{red}
លំហាត់
\begin{enumerate}[label=\NK\kalph*.]
\item
\item
\end{enumerate}
\end{KP}
\end{document}