The document reproduced below has a problem with the margin note going outside the page. If I remove the package classicthesis then the problem solves: the note stays inside the page. So there is a problem of interaction with classicthesis (I had many, but I like so much the style of classicthesis and I would like to keep it). If I experiment with the file classicthesis.sty (see http://ctan.mirror.garr.it/mirrors/CTAN/macros/latex/contrib/classicthesis/classicthesis.sty) I find that the problem is caused by the lines
\setlength{\marginparwidth}{...}%
\setlength{\marginparsep}{...}%
which redefine the dimensions of the margin. If I remove all these lines (there are many "if" branches and I'm not sure which is executed) the problem solves.
What is the best way to fix this problem? Maybe I should redefine these length to the default value, but how I find what is the default value? Maybe I can customize the file classicthesis, but I don't feel comfortable with this option. Any suggestion would be appreciated.
added: the problem is maybe also caused by the interaction with the geometry package. I need custom page size and I'm not sure what is the correct way to provide it: after many iterations I find as the only solution to load the geometry package after classicthesis. Not sure if it is the correct way to go.
\documentclass[italian,twoside,headinclude]{scrbook}
\usepackage{amsmath,amssymb,amsthm,thmtools}
\usepackage{babel}
\usepackage[nochapters,pdfspacing]{classicthesis}
\usepackage[paperwidth=7in,paperheight=10in,bindingoffset=0.625in]{geometry}
\usepackage[utf8]{inputenc}
\usepackage{sidenotes}
\usepackage{marginnote}
\usepackage{mparhack} % fix margin notes (otherwise sometime they go to wrong margin!)
\newcommand{\mymark}[1]{\reversemarginpar\marginnote{#1}\normalmarginpar}
\newcommand{\mynote}[1]{\marginnote{{\footnotesize #1}}}
\newcommand{\mymargin}[1]{\mynote{#1}\index{#1}}
\newcommand{\myemph}[1]{\emph{#1}\mynote{#1}\index{#1}}
\declaretheoremstyle[
spaceabove=6pt, spacebelow=6pt,
headfont=\normalfont\bfseries\itshape,
notefont=\mdseries, notebraces={(}{)},
bodyfont=\normalfont,
postheadspace=1em,
qed=,
%shaded={rulecolor=pink!30,rulewidth=1pt,bgcolor=pink!10}
]{exercise_style}
\declaretheoremstyle[
spaceabove=6pt, spacebelow=6pt,
postheadspace=1em,
qed=,
%shaded={rulecolor=yellow!50,rulewidth=1pt,bgcolor=yellow!5}
]{axiom_style}
\declaretheorem[name=Teorema,numberwithin=chapter]{theorem}
\declaretheorem[style=axiom_style,name=Assioma,sibling=theorem]{axiom}
\begin{document}
\begin{axiom}[campo ordinato]
\mynote{campo ordinato}
\index{campo!ordinato}
Le operazioni di campo e l'ordinamento sono compatibili nel senso che
valgono le seguenti proprietà:
\begin{enumerate}
\item positività: se $x\ge 0$ e $y \ge 0$ allora $x+y \ge 0$ e $x\cdot y\ge 0$;
\item monotonia: se $x \ge y$ allora $x+z \ge y+z$.
\end{enumerate}
\end{axiom}
\end{document}