\documentclass{article}
\usepackage{web}
\margins{0pt}{0pt}{0pt}{0pt}   %% Kein Seitenrand
\screensize{100mm}{150mm}      %% Dimensionen: H\"{o}he, Breite des Dokuments

\parindent0pt

\usepackage{pstricks,pstricks-add}

\definecolor{romaniaBlue}{RGB}{0 43 127}
\definecolor{romaniaYellow}{RGB}{252 209 22}
\definecolor{romaniaRed}{RGB}{206 17 38}

\begin{document}

\thispagestyle{empty}

\begin{pspicture}(0,0)(15,10)
%% Flagge (Verh\"{a}ltnis 3 Breite : 2 H\"{o}he)
\psframe[linecolor=romaniaBlue,fillstyle=solid,fillcolor=romaniaBlue](0,0)(5,10)
\psframe[linecolor=romaniaYellow,fillstyle=solid,fillcolor=romaniaYellow](5,0)(10,10)
\psframe[linecolor=romaniaRed,fillstyle=solid,fillcolor=romaniaRed](10,0)(15,10)
\end{pspicture}
\end{document}
