config.tex

\usepackage[utf8]{inputenc} % Permite caracteres acentuados
\usepackage[IL2]{fontenc}
\usepackage[czech]{babel}
\usepackage[a4paper, top=2cm, left=2cm, right=2cm, bottom=2.54cm]{geometry}

\usepackage[unicode]{hyperref}
\usepackage{xfrac}
\usepackage{enumitem}

\setlist[enumerate]{itemsep=0.05\baselineskip, topsep=0cm}

\setcounter{secnumdepth}{2} % Profundidade da numeração
\setcounter{tocdepth}{1} % Profundidade do sumário

\usepackage{titlesec}

\titleformat{\chapter}[block]
{\normalfont\large\bfseries\centering}{ČÁST \thechapter.\\}{0em}{\LARGE} 
\titleclass{\chapter}{straight}

\titleformat{\section}[block]
{\normalfont\normalsize\bfseries}{}{0.5em}{Článek \thesection. } 

\titlespacing*{\chapter}
{0pt}{1cm}{1\baselineskip}

\usepackage{titletoc}%
\titlecontents{chapter}% <section-type>
  [0pt]% <left>
  {\bfseries}% <above-code>
  {\chaptername\ \thecontentslabel.\quad}% <numbered-entry-format>
  {}% <numberless-entry-format>
  {\hfill\contentspage}% <filler-page-format>

\renewcommand{\thechapter}{\Roman{chapter}}
\renewcommand{\thesection}{\arabic{section}}
%\renewcommand{\thesubsection}{\Roman{subsection}}

\setlength{\parindent}{0pt}

\usepackage{enumitem}

\makeatletter
\@removefromreset{section}{chapter}
\makeatother