答案1
你可以使用背景。您没有给出最小的例子,因此您的公里数可能会有所不同:
\documentclass[a4paper]{article}
\usepackage{geometry,tikz}
\usetikzlibrary{calc}
\usepackage[placement=bottom,scale=1,opacity=1]{background}
\backgroundsetup{contents={%
\begin{tikzpicture}
\fill [red] (current page.north west) rectangle ($(current page.north east)!.2!(current page.south east)$) coordinate (a);
\fill [yellow] (current page.south west) rectangle (a);
\end{tikzpicture}}}
\usepackage{kantlipsum}
\begin{document}
\kant[1-5]
\end{document}