\documentclass{article}
\usepackage{tikz}
\usepackage{ifthen}
\usepackage{xcolor}
\usetikzlibrary{shadows.blur}

\newlength{\forkmeoffset}
\setlength{\forkmeoffset}{12em}
\definecolor{forkmebg}{HTML}{CC0000}
\definecolor{forkmefg}{HTML}{EEEEEE}

\newcommand{\forkme}[1][west]{
	\ifthenelse{\equal{#1}{east}}{%
		\tikzset{forkmerot/.style={rotate=-45}}
	}{%
		\tikzset{forkmerot/.style={rotate=45}}
	}
	\begin{tikzpicture}[remember picture, overlay]
	\node[forkmerot, shift={(0, -\forkmeoffset)}] at (current page.north #1) {
		\begin{tikzpicture}[remember picture, overlay]
		\node[fill=forkmebg, text centered, minimum width=50em, minimum height=3.0em, blur shadow, shadow yshift=0pt, shadow xshift=0pt, shadow blur radius=.4em, shadow opacity=50, text=forkmefg](fmogh) at (0pt, 0pt) {   \fontfamily{phv}\selectfont\bfseries Fork me on GitHub};
		\draw[forkmefg!60, dashed, line width=.08em, dash pattern=on .5em off 1.5\pgflinewidth] (-25em,1.2em) rectangle (25em,-1.2em);
		\end{tikzpicture}
	};
	\end{tikzpicture}
}

\begin{document}
\forkme[west]
{\LARGE\colorlet{forkmebg}{blue} \setlength{\forkmeoffset}{8cm} \forkme[east]}

    Variables include:
    \begin{itemize}
		\item \texttt{{\textbackslash}forkme[west]} vs \texttt{{\textbackslash}forkme[east]}
		\item shift offset (length: \texttt{{\textbackslash}forkmeoffset})
		\item node fill color (color: \texttt{forkmebg})
		\item text and line color (color: \texttt{forkmefg})
		\item text size: inherited from surrounding context
	\end{itemize}
\end{document}