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\addtolength{\voffset}{+6.0cm}
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\begin{document}
\begin{center}

    {\Huge \bf Certyfikat Uczestnictwa}

\vspace{1.0cm}

{\huge \emph{FILLER_NAME}}

\vspace{0.75cm}


\linespread{1.2}
{\Large
FILLER_TAKE udział w \\ {\bf Wakacyjnych Warsztatach Informatycznych 2023}\\
}
\end{center}

\vspace{1.5cm}
\noindent
\begin{minipage}{0.4999\textwidth}
    \centering
\large Kierownik obozu
\end{minipage}
\begin{minipage}{0.4999\textwidth}
    \centering
\large Kadra WWI
\end{minipage}

\vspace{7.75cm}
\begin{center}
{\Huge Lublin 2023}
\end{center}

\pagebreak

\end{document}