改变展示框的颜色、间距、线条样式（几何包）

Question

如何改变geometry包showframe选项生成的规则的颜色、间距、线条样式等？

Answer 1

编译并阅读此 MWE：

\documentclass[a4paper]{scrartcl}
\usepackage{xcolor}
\usepackage[showframe]{geometry}
\usepackage{microtype} 
\usepackage{lipsum}
\makeatletter
\def\Gm@hrule{\color{red!20}\hrule height 4pt depth\z@ width\textwidth}%
\def\Gm@vrule{\color{red!20}\vrule width 4pt height\textheight depth\z@}%
\def\Gm@hruled{\color{red!20}\hrule height\z@ depth4pt width\textwidth}%

\makeatother

\title{How to change the color of \texttt{showframe}}
\author{Fran}
\date{\today}
\begin{document}
\maketitle

\section{Introduction}

You need change the rules. Not all those of the society, but only the three
defined in \verb|geometry.sty| with the macros 
\verb|\Gm@vrule|  \verb|\Gm@hrule| and  \verb|\Gm@hruled|. 
Thus, simply define again these rules in your preamble, adding some color. 
Of course, include before the  \verb|color| or \verb|xcolor| package.

As these commands contain the character @, remember that you need put 
these definitions in a  \verb|\makeatletter| \dots  \verb|\makeatother| group.

The rest of this the \verb|lipsum| dummy text of any decent 
minimal  working example. 
You do not need read the following text.  \lipsum[1]

\lipsum[2-3]

\end{document}

Answer 2

内部宏\Gm@pageframes设置框架，因此可以扩展以添加颜色：

\documentclass{article}
\usepackage{lipsum,microtype}
\usepackage[a6paper,showframe]{geometry}
\usepackage{xcolor}

\colorlet{showframe}{red}
\makeatletter
\let\org@Gm@pageframes\Gm@pageframes
\renewcommand*{\Gm@pageframes}{%
  \begingroup
    \color{showframe}%
    \org@Gm@pageframes
  \endgroup
}
\makeatother

\begin{document}
\section{Hello World}
\lipsum[2]
\end{document}