테이블의 회색 셀에 수직선이 표시되도록 하려면 어떻게 해야 합니까?
\begin{table}[ht!]
\renewcommand{\arraystretch}{1}
\normalsize
\doublespacing
\centering
\caption{Interaction between \emph{Import Industry} and \emph{Neutral Sentiment}.}
\begin{tabular}{|c|c|c|c|}
\hline
& DV=\emph{Bad Self Impact} & DV=\emph{Bad US Impact} & DV=\emph{Tariff Support}\\ \hline
\emph{Import Industry} & 0.119 & 0.002 & 0.250 \\
& (0.342) & (0.985) & (0.011)\\ \hline
\emph{Neutral Sentiment} & 0.045 & -0.008 & -0.064 \\
& (0.688) & (0.942) & (0.481)\\ \hline
\cellcolor[gray]{0.8}\emph{Import Industry*} & \cellcolor[gray]{0.8}0.470 & \cellcolor[gray]{0.8}0.500 & 0.267\\
\cellcolor[gray]{0.8}\emph{Neutral Sentiment} & \cellcolor[gray]{0.8}{0.024} & \cellcolor[gray]{0.8}{0.014} & 0.130\\ \hline
\end{tabular}\\
\end{table}