I am trying to make a diary that will have a book-like page structure with side notes in A5/B5 paper size. I was able to create the style I want, but it can only be applied using an article documentclass.
The idea is to have a diary.tex in which there is Gonzalo Medina's code for caution side notes from create a framed environment for a margin note as well as Ferahfeza's code for Colored Boxed Diary Entries from Using LaTeX to keep a diary.
The diary.tex that works with a4paper and article is the following
%%%%%%%%%%%%%%~~~~~~~~~~Caution Side Note~~~~~~~~~%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage[lmargin=5cm,textwidth=15cm,marginparwidth=4cm]{geometry}
\reversemarginpar
\newsavebox\mybox
\newlength\BoxHt
\newcommand\caution[2][-2.2\baselineskip]{%
\begin{lrbox}{\mybox}
\parbox{\marginparwidth}{#2}
\end{lrbox}%
\settoheight\BoxHt{\usebox\mybox}%
\raisebox{\BoxHt}[0pt][0pt]{\marginnote{%
\begin{mdframed}[
userdefinedwidth=\marginparwidth,
innerleftmargin=3pt,
innerrightmargin=3pt,
linecolor=BrickRed,
frametitle=\colorbox{white}{\space Caution\space},
frametitlefont=\color{BrickRed}\sffamily,
innertopmargin=10pt,
frametitleaboveskip=-\ht\strutbox,
frametitlebelowskip=-\ht\strutbox,
frametitlealignment=\raggedright,
singleextra={\fill[BrickRed] let \p1=(P), \p2=(O) in
( $ (P|-0,0.5*\y2+0.5*\y1) + (0,-4pt) $ ) -- +(4pt,4pt) -- +(0,8pt) -- cycle;}
]\RaggedRight\small#2\end{mdframed}}[#1]}}
%%%%%%%%%%%%%%~~~~~~~~~~Colored Boxed Diary Entries~~~~~~~~~%%%%%%%%%%%%%%%%%%%%%%%%%%
\newlength\sidebar
\newlength\envrule
\newlength\envborder
\setlength\sidebar{1.5mm}
\setlength\envrule{0.4pt}
\setlength\envborder{2mm}
\makeatletter
\long\def\fboxs#1{%
\leavevmode
\setbox\@tempboxa\hbox{%
\color@begingroup
\kern\fboxsep{#1}\kern\fboxsep
\color@endgroup}%
\@frames@x\relax}
\def\frameboxs{%
\@ifnextchar(%)
\@framepicbox{\@ifnextchar[\@frameboxs\fboxs}}
\def\@frameboxs[#1]{%
\@ifnextchar[%]
{\@iframeboxs[#1]}%
{\@iframeboxs[#1][c]}}
\long\def\@iframeboxs[#1][#2]#3{%
\leavevmode
\@begin@tempboxa\hbox{#3}%
\setlength\@tempdima{#1}%
\setbox\@tempboxa\hb@xt@\@tempdima
{\kern\fboxsep\csname bm@#2\endcsname\kern\fboxsep}%
\@frames@x{\kern-\fboxrule}%
\@end@tempboxa}
\def\@frames@x#1{%
\@tempdima\fboxrule
\advance\@tempdima\fboxsep
\advance\@tempdima\dp\@tempboxa
\hbox{%
\lower\@tempdima\hbox{%
\vbox{%
%\hrule\@height\fboxrule
\hbox{%
\vrule\@width\fboxrule
#1%
\vbox{%
\vskip\fboxsep
\box\@tempboxa
\vskip\fboxsep}%
#1%
}%\vrule\@width\fboxrule}%
}%\hrule\@height\fboxrule}%
}%
}%
}
\def\esefcolorbox#1#{\esecolor@fbox{#1}}
\def\esecolor@fbox#1#2#3{%
\color@b@x{\fboxsep\z@\color#1{#2}\fboxs}{\color#1{#3}}}
\makeatother
\definecolor{exampleborder}{HTML}{FE642E}
\definecolor{examplebg}{HTML}{CEF6EC}
\definecolor{statementborder}{rgb}{.9,0,0}
\definecolor{statementbg}{rgb}{1,1,1}
\newenvironment{eseframed}{%
\def\FrameCommand{\fboxrule=\the\sidebar \fboxsep=\the\envborder%
\esefcolorbox{exampleborder}{examplebg}}%
\MakeFramed{\FrameRestore}}%
{\endMakeFramed}
\newcounter{diary}
\renewcommand{\thediary}{\arabic{diary}}
%%% CODE ENVIRONMENT. PUT TEXT INTO COLORED FRAME %%%
\newenvironment{diary}[2]
{\par\medskip\refstepcounter{diary}%
\hbox{%
\fboxsep=\the\sidebar\hspace{-\envborder}\hspace{-.5\sidebar}%
\colorbox{exampleborder}{%
\hspace{\envborder}\footnotesize\sffamily\bfseries%
\textcolor{white}{{#1}\ {#2}\enspace\hspace{\envborder}}
}
}
\nointerlineskip\vspace{-\topsep}%
\begin{eseframed}\noindent\ignorespaces%
}
{\end{eseframed}\vspace{-\baselineskip}\medskip}
The main.tex file is the following
\documentclass[]{article}
%\usepackage[b5paper, %paper size
%hmargin=1.0cm, %horizontal margin = 1 cm on each side
%vmargin=1.0cm, %vertical margin = 1 cm top and bottom
% tmargin=1.2cm, %top margin = 1.2 cm
% bmargin=0.8cm, %bottom margin = 0.8 cm
%]{geometry}
\usepackage[dvipsnames]{xcolor}
\usepackage{ragged2e}
\usepackage[framemethod=tikz]{mdframed}
\usepackage{marginnote}
\usetikzlibrary{calc}
\usepackage{lipsum}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage{framed}
\usepackage{datetime}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{times}
\input{diary}
\begin{document}
\begin{diary}{}{14.07.2013}
\lipsum*[3-4] \caution{\lipsum[2]} \lipsum[3-5]
\end{diary}
\begin{diary}{}{14.07.2013}
\lipsum*[3-4]\caution{\lipsum[2]}\lipsum[3-5]
\end{diary}
\begin{diary}{}{14.07.2013}
\lipsum*[3-4]\caution{\lipsum[2]}\lipsum[3-5]
\end{diary}
\begin{diary}{}{14.07.2013}
\lipsum*[3-4]\caution{\lipsum[2]}\lipsum[3-5]
\end{diary}
\end{document}
I tried to use \documentclass[a5paper]{article} and \documentclass{book} but the oupput is really ugly and messed up.

What can be done to have a nice two-sided diary(like a book) in a5/b5 size?
