%! TEX program = xelatex
% vim: set spell spelllang=de:
\documentclass{scrreprt}

\KOMAoptions{
 % layout
 DIV=11,
 usegeometry,
 % fonts
 fontsize=12pt,
 parskip=half,
 % structure
 bibliography=totoc, % add bibliography to toc
}

% hyphenation
\usepackage[ngerman]{babel}

% hyperlinks and pdf toc
\usepackage[unicode, hidelinks]{hyperref}
\usepackage{bookmark}

% cretion of nice dates from numbers
\usepackage[useregional]{datetime2}

% dummy text
\usepackage{lipsum}

% roman font for title
%\addtokomafont{disposition}{\rmfamily}

% line height
\usepackage{setspace}

% specified page margins
\usepackage[left=25mm, right=35mm]{geometry}

% bibliography
\usepackage{csquotes}
\usepackage[
 style=geschichtsfrkl, % implements my citation requirements almost perfectly
]{biblatex}
\addbibresource{bibliography.bib}

\subject{Seminararbeit}
\title{Albert Göring: Der gute Göring?}
\subtitle{Untertitel}
\author{Simon Bruder}
\date{\DTMdisplaydate{2021}{01}{01}{-1}}

\begin{document}
\maketitle

% toc
\phantomsection

% no page numbers on toc pages
\pagestyle{empty}
\renewcommand*{\chapterpagestyle}{empty}
\tableofcontents
\clearpage
\pagestyle{plain}
\renewcommand*{\chapterpagestyle}{plain}

% main
\onehalfspacing

\chapter{Einleitung}

\lipsum

\chapter{Hauptteil}

\section{lol}

\lipsum\cite[17]{latexcompanion}
\lipsum\cite[vgl.][43f.]{latexcompanion}

\section{foo}

\lipsum

\chapter{Schluss}

\lipsum

% appendix
\appendix
\singlespacing

% bibliography
\printbibliography

\chapter*{Eigenständigkeitserklärung}
\addcontentsline{toc}{chapter}{Eigenständigkeitserklärung}

\lipsum

\end{document}