When I try to make the checkmark black using the following code, it doesn't work; the checkmark shows up red. How do I make it black?
\documentclass{beamer}
\usepackage{amsmath, amsthm, amssymb, amsfonts}
\usepackage{color, xcolor, graphicx}
\usepackage[english]{babel}
\usetheme{Warsaw}
\usecolortheme{beaver}
\setbeamercolor{math text}{fg=darkred!70!black}
\begin{document}
\begin{frame}{Title}
\begin{block}{Example}
Let $G = <a, b, c \mid [ab], [bc]>$, $w_1 = c$, and $w_2 = ab$.
Shortest? \pause \textcolor{black}{\checkmark}
\end{block}
\end{frame}
\end{document}
$...$
:$\textcolor{black}{\checkmark}$