# Grey (not black) shadow box?

I would like to change the default color of a shadowbox to grey. How to do that with no problem of equation "style"/"management" inside the shadowbox ?

Thank you very much

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Please add a fully compilable minimal working example (MWE) that illustrates your problem. – canaaerus Aug 2 '12 at 12:35

Here's one possibility defining commands \Cshadowbox and \@Cshadowbox analogously to \shadowbox and \@shadowbox as implemented in fancybox.sty; the color can be changed using ShadowColor:

\documentclass{article}
\usepackage{xcolor}
\usepackage{fancybox}

\makeatletter
\setbox\@fancybox\hbox{\fbox{#1}}%
\leavevmode\vbox{%
\offinterlineskip
\vskip\dimexpr-\dimen@+0.5\fboxrule\relax
\makeatother

\begin{document}

\shadowbox{$a=b$}

\Cshadowbox{$a=b$}

\Cshadowbox{$a=b$}
\Cshadowbox{$a=b$}