References & Bibliography in Beamer with different colors

Question

How can I change the color of \footfullcite in beamer? The example citation below is blue and black but I need everything in white (because I have a black background).

For the minimal example I took the solution of the question References & Bibliography in Beamer. However, biber did't worked for my, I used bibtex. But this is not the question.

Because of the fact that I use a black background for my presentation and a white one for the handout, I need different colors for the citation itself.

The following example can be compiled with pdflatex, bibtex, 2x pdflatex

\documentclass[10pt,handout,english]{beamer}
\usepackage[english]{babel}
\usepackage[backend=bibtex,style=authoryear]{biblatex}
\usepackage{filecontents}
\begin{filecontents}{bib2.bib}
@book{knuth,
  author       = {Knuth, Donald E.},
  title        = {The {\TeX} book},
  date         = 1984,
  maintitle    = {Computers & Typesetting},
  volume       = {A},
  publisher    = {Addison-Wesley},
  location     = {Reading, Mass.},
  langid       = {english},
  langidopts   = {variant=american},
  sortyear     = {1984-1},
  sorttitle    = {Computers & Typesetting A},
  indexsorttitle= {The TeXbook},
  indextitle   = {\protect\TeX book, The},
  shorttitle   = {\TeX book}
}
\end{filecontents}
\addbibresource{bib2.bib}
\begin{document}
\begin{frame}
\frametitle{Title}
 A reference\footfullcite{knuth}, with refbib an item of the .bib file.
\end{frame}
\begin{frame}[allowframebreaks]
        \frametitle{References}
\printbibliography
\end{frame}
\end{document}