% Double-line for start and end of epigraph.
newcommand{epiline}{hrule vskip -.2em hrule}
% Massively humongous opening quotation mark.
newcommand{hugequote}{%
  fontsize{42}{48}selectfontcolor{quotationmarkcolour}textbf{``}%
  vskip -.5em%
}

% Make the box around quotations fit snugly to the epilines.
setlengthfboxrule{0pt}
setlengthfboxsep{0pt}

% Beautify quotations.
newcommand{epigraph}[2]{%
  vskip -1.5em%
  colorbox{quotationcolour}{%
    begin{minipage}{linewidth}%
    hangindent 1.1em%
    epiline vskip 1em {hugequote} vskip -.5em%
    parindent 2.2em%
    setlengthmarginparsep{-1.1em}%
    #1begin{flushright}color{quotationmarkcolour}textsc{#2}hspace*{1em} ~end{flushright}%
    epiline%
    end{minipage}%
  }%
  bigskip
}

newcommand{epigraph}[2]{%
  vskip -1.5em%
  colorbox{quotationcolour}{%
    begin{minipage}{linewidth}%
    dimen0linewidth
    advancedimen0 by -3.3em
    hangindent 1.1em%
    epiline vskip 1em hspace{1.1em}{hugequote} vskip -.5em%
    hspace{1.1em}
    parbox{thedimen0}{
        parindent 2.2em%
        setlengthmarginparsep{-1.1em}%
        #1}%
    begin{flushright}color{quotationmarkcolour}textsc{#2}hspace*{1em} ~end{flushright}%
    epiline%
    end{minipage}%
  }%
  bigskip
}

begin{minipage}{linewidth-6pt}%