main.tex

\documentclass[a4paper, english]{book}

\usepackage{geometry} % Title page needs its own margins.

%\usepackage[english]{babel} % Hyphenation rules, date format, etc. in English
\usepackage[main=english, ngerman]{babel}
%\usepackage[german]{babel} % Hyphenation rules, date format, etc. in English
\usepackage[T1,EU1]{fontenc}
%\usepackage{fontspec}
\usepackage{polyglossia}
%\setmainlanguage[babelshorthands=true]{english}
\setmainlanguage{english}
%\usepackage[T1]{fontenc}    % European character set (special characters, etc.)
\usepackage[bitstream-charter]{mathdesign} % Modern, serif, and objective font
%\usepackage[utf8]{inputenc} % UTF-8 input character set
\usepackage[section]{placeins}
\usepackage{xstring}        % Test/compare (sub)strings

\usepackage{totcount}       % Count page numbers, figures, etc.

\usepackage{siunitx}        % SI units
%\usepackage{natbib}         % Scientific citations
\usepackage[printonlyused]{acronym} % Abbreviations + abbreviation directory
\usepackage{blindtext}      % Filler text for testing

\usepackage[language=english, sorting=none, backend=biber, style=numeric, maxnames=99]{biblatex}
\addbibresource{bibliography/bibliography.bib}

\usepackage{pdfpages}       % Include PDFs

%% Custom Macros
\input{config/config}
\input{macros/InOderAm}
\input{macros/HideIfZero}
\input{macros/citenumCounter}
\input{macros/totalfiguresCounter}
\input{macros/totalappendixCounter}
\usepackage{amsmath}
\usepackage{booktabs}
\usepackage{bm}
\usepackage{textcomp}
\usepackage[x11names]{xcolor} % For color options
\usepackage{graphicx}
\usepackage{caption}
\usepackage{subcaption}
\usepackage{subfig}
\usepackage{svg}

\usepackage{etoolbox}
\usepackage{gensymb}
\begin{document}
%% Document
%\begin{document}

%% Title Page
\input{official/titelblatt_pretty}

%% Line number for the table of contents, etc.
%\pagenumbering{Roman}

% Modify the \frontmatter to not number any headings
\apptocmd{\frontmatter}{%
    \setcounter{secnumdepth}{-1}%
}{}{}
% Modify the \mainmatter to reset that
\apptocmd{\mainmatter}{%
    \setcounter{secnumdepth}{2}%
}{}{}

%% TOC
\tableofcontents
\newpage

%\pagenumbering{arabic}
%% Bibliographic Description
\frontmatter
\input{content/head/bibliographische_beschreibung}
\input{content/head/abkuerzungsverzeichnis}
\newpage

\setcounter{page}{1}
\mainmatter
%% Main Part
\input{content/main/main}

%% Final Part

%% Summary
\input{content/tail/zusammenfassung}
%% Bibliography
\input{content/tail/literaturverzeichnis}
%% Appendix
\input{content/tail/appendix}
\end{document}