Fix title page color related error with pdflatex

eisvogel.latex

@@ -501,7 +501,7 @@ $endif$
 \begin{flushleft}
 \noindent
 \\[-1em]
-\color[HTML]{$if(titlepage-text-color)$$titlepage-text-color$$else$5f5f5f$endif$}
+\color[HTML]{$if(titlepage-text-color)$$titlepage-text-color$$else$5F5F5F$endif$}
 \makebox[0pt][l]{\colorRule[$if(titlepage-rule-color)$$titlepage-rule-color$$else$435488$endif$]{1.3\textwidth}{$if(titlepage-rule-height)$$titlepage-rule-height$$else$4$endif$pt}}
 \par
 \noindent
@@ -578,4 +578,4 @@ $for(include-after)$
 $include-after$
 
 $endfor$
-\end{document}
+\end{document}