% =============================================================================
% qgc.sty -- shared preamble for the Quantum-Geometric Correspondence series
% =============================================================================
% One package, loaded by every paper, holding the boilerplate that was formerly
% duplicated across ~13 per-paper preamble.tex files (packages, theorem
% environments, the key-result box, the abstract styling, and the author block).
%
% A paper's preamble.tex reduces to:
%     \documentclass[11pt,a4paper]{article}
%     \usepackage{qgc}
%     \usepackage{qgc-notation}            % optional shared physics macros
%     \hypersetup{pdftitle={...}, pdfkeywords={...}}
%     \title{...}\author{\qgcauthor}\date{\today}
%
% Designed for arXiv submission (gr-qc, quant-ph); PRD/JHEP conventions.
% =============================================================================
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{qgc}[2026/06/08 Quantum-Geometric Correspondence shared preamble]

% --- Encoding & fonts --------------------------------------------------------
\RequirePackage[utf8]{inputenc}
\RequirePackage[T1]{fontenc}
\RequirePackage{lmodern}
\RequirePackage{microtype}

% --- Page layout -------------------------------------------------------------
\RequirePackage[margin=1in,headheight=14pt]{geometry}
\RequirePackage{setspace}
\setstretch{1.15}

% --- Mathematics -------------------------------------------------------------
\RequirePackage{amsmath,amssymb,amsthm}
\RequirePackage{mathtools}
\RequirePackage{mathrsfs}
\RequirePackage{braket}

% --- Figures & tables --------------------------------------------------------
\RequirePackage{graphicx}
\RequirePackage{float}
\RequirePackage{booktabs}
\RequirePackage{array}
\RequirePackage{multirow}
\RequirePackage[font=small,labelfont={bf},textfont={it},labelsep=period,skip=8pt]{caption}

% --- Colours & links ---------------------------------------------------------
\RequirePackage[dvipsnames]{xcolor}
\RequirePackage[colorlinks=true,
            linkcolor=MidnightBlue,
            citecolor=MidnightBlue,
            urlcolor=MidnightBlue,
            pdfauthor={Marc Sperzel}]{hyperref}
% Papers set their own pdftitle / pdfsubject / pdfkeywords via \hypersetup{...}.

% --- Theorem environments ----------------------------------------------------
\theoremstyle{plain}
\newtheorem{theorem}{Theorem}[section]
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{corollary}[theorem]{Corollary}
\newtheorem{proposition}[theorem]{Proposition}
\newtheorem{conjecture}[theorem]{Conjecture}
\newtheorem{hypothesis}[theorem]{Hypothesis}

\theoremstyle{definition}
\newtheorem{definition}[theorem]{Definition}

\theoremstyle{remark}
\newtheorem{remark}{Remark}[section]
\newtheorem*{remark*}{Remark}

% --- Boxed key results -------------------------------------------------------
\RequirePackage{tcolorbox}
\tcbuselibrary{theorems,skins}
\newtcolorbox{keyresult}{
    colback=gray!5, colframe=gray!50, boxrule=0.5pt,
    arc=2pt, left=8pt, right=8pt, top=6pt, bottom=6pt
}

% --- Abstract styling --------------------------------------------------------
\renewenvironment{abstract}{%
    \small
    \begin{center}\textbf{Abstract}\end{center}
    \begin{quotation}\noindent
}{%
    \end{quotation}\vspace{1em}
}

% --- Standard author block ---------------------------------------------------
% Use \author{\qgcauthor} for the canonical byline.
\newcommand{\qgcauthor}{%
    Marc Sperzel\thanks{ORCID: \href{https://orcid.org/0009-0000-6252-3155}{0009-0000-6252-3155}.
    Email: \texttt{me@marcsperzel.com}}\\[0.3cm]
    \small\textit{Independent Researcher}%
}


% Appendix headings read "Appendix A: Title", so the reader sees where the main text ends.
% \thesection is unchanged, so "Appendix~\ref{...}" in the text still prints "Appendix A".
\let\qgc@origappendix\appendix
\renewcommand{\appendix}{%
  \qgc@origappendix
  \renewcommand{\@seccntformat}[1]{%
    \ifnum\pdfstrcmp{##1}{section}=0 Appendix~\thesection:\ \else\csname the##1\endcsname\quad\fi}%
}

\endinput