我在使用 tcolorbox 的框内使用两列布局列表时遇到了一些困难。我需要像附图一样的输出。请建议如何修复此问题，我的 TeX 编码如下：
梅威瑟：
\documentclass{book}
\usepackage[most,raster]{tcolorbox}
\tcbuselibrary{breakable,hooks,skins}
\usepackage{eso-pic,graphicx,transparent}
\usepackage{multicol}
\newtcolorbox{QandPbox} {breakable,enhanced,raster columns=2,width=600pt, underlay last={\node[anchor=north east] at ([yshift=0mm]frame.north east) {};}, arc=0pt,outer arc=0pt,boxrule=0pt,boxsep=0pt,top=9pt,left=62.8pt,right=67pt,bottom=39pt,middle=0pt,enlarge left by=-100pt,enlarge right by=180pt, colback=black!30% , colbacktitle=black!30, colframe=black!30, }
\newenvironment{QandP} {\begin{QandPbox}\begin{multicols}{2}}{\end{multicols}\end{QandPbox}}
\begin{document}
\begin{QandP}
\begin{enumerate} \item{} Our book is intended for senior undergraduate students of modern abstract algebra. Those more gifted in mathematics can well profit from it sooner.
\item{}Beginning graduate students who need a refresher could find it useful as well.
\item{} For pairs of small integers, their greatest common divisor can be seen by inspection.
\item{} For instance, gcd(42; 30) = 6. When the integers become large, there is an efficient technique for finding their greatest common divisor, based on repeated use of Euclidean division.
\end{enumerate}
\end{QandP}
\end{document}
