\color{cyan}{\foreach \n in {a,b,c,d,e,f,g,h,i,j,k,l,m}{ \foreach \i in {a,b,c,d,e,f,g,h,i,j,k,l,m}{\!\!\rule[0pt]{\baselineskip}{0.5pt} \begin{rotate}{90}\rule[15pt]{\baselineskip}{0.5pt}\end{rotate}}\\} }