我该怎么做才能修复这个问题？此代码：
\documentclass[12pt]{article}
\begin{document}
\renewcommand\labelitemi{\rule{.3in}{.1pt}}
\fbox{\begin{minipage}{3in}
\begin{itemize}
\item This looks good
\item That looks good
\item Oh no, a dim line
\end{itemize}
\end{minipage}}
\end{document}
使得：
