\documentclass[12pt,landscape]{article}
\usepackage[a4paper,margin=1.5cm]{geometry}
\usepackage{fontspec}
\usepackage{xcolor,tikz}
\pagestyle{empty}
\definecolor{navy}{HTML}{132B62}
\begin{document}
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\begin{center}
\vspace*{1.5cm}
{\Huge\bfseries\color{navy} Certificate of Achievement}\\[1.2cm]
{\Large This certificate is presented to}\\[6mm]
{\huge\bfseries Samira Ahmed}\\[8mm]
{\Large for successfully completing the LatexDesk Workshop}\\[1.2cm]
\begin{tabular}{c@{\hspace{4cm}}c}
1 September 2026 & Program Director\\[-1mm]
\rule{5cm}{0.4pt} & \rule{5cm}{0.4pt}
\end{tabular}
\end{center}
\end{document}