\documentclass{scrbook}
\usepackage{CJKutf8}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{microtype}
\usepackage{colortbl}
\usepackage{tcolorbox}
\usepackage{graphics}
\usepackage{tabularx}

\newcommand{\jp}[1]{\begin{CJK*}{UTF8}{min}#1\end{CJK*}}
\newcommand{\bul}[1]{\underline{\textbf{#1}}}
\newcommand{\rarr}{$\rightarrow$}
\definecolor{ForestPrimary}{HTML}{2E5339}
\definecolor{ForestLight}{HTML}{EAF2EB}
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  left=6pt, right=6pt, top=4pt, bottom=4pt, breakable,
  fonttitle=\bfseries, title={#1}
}
\title{Letteratura Giapponese \roman{1}}
\author{Marianna}
\begin{document}
\chapter{Lezione 1}
\input{./chapt/lezione1.tex}
\end{document}