homework.sty

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{homework}

\usepackage[margin=1in]{geometry}

\usepackage[usenames,dvipsnames]{xcolor}
\usepackage[many]{tcolorbox}

\usepackage{mathtools,amsthm,amssymb,amsfonts,bm}
\usepackage{thmtools,amsmath}
\usepackage{marginnote,sidenotes}
\usepackage{fancyhdr}   
\usepackage{titlesec}
\usepackage{setspace}
\usepackage{enumitem}
\usepackage{graphicx, svg}

\usepackage[bookmarks=true]{hyperref} 
\usepackage{bookmark}

%% Constants %%

    % Making epsilons look like epsilons...
    \renewcommand{\epsilon}{\varepsilon}

    \newcommand{\eps}{\epsilon}
    \newcommand{\A}{\forall}
    \newcommand{\E}{\exists}
    \newcommand{\N}{\mathbb{N}}
    \newcommand{\Q}{\mathbb{Q}}
    \newcommand{\R}{\mathbb{R}}
    \newcommand{\Z}{\mathbb{Z}}
    
%% Frequently-used snippets %%

    \newcommand{\abs}[1]{\left| #1 \right|}
    \newcommand{\absle}[1]{\abs{#1} < \eps}
    \newcommand{\absld}[1]{\abs{#1} < \delta}
    
    \newcommand{\integral}[2]{\int_{#1}^{#2}}
    \newcommand{\intab}{\integral{a}{b}}
    
    \newcommand{\func}[2][f]{#1 \colon #2 \to \R}
    \newcommand{\fabr}{\func[f]{[a,b]}}
    \newcommand{\fog}{f \circ g}
    \newcommand{\gof}{g \circ f}
    
    \newcommand{\set}[1]{\left\{ #1 \right\}}
    \newcommand{\partition}[1][P]{#1 = \set{x_0,x_1,\ldots,x_n}}
    
    \newcommand{\deltaxi}{\Delta x_{i}}
    \newcommand{\deltaxk}{\Delta x_{k}}
    \newcommand{\lowersum}[1][f]{L(#1,P) = \sum^n_{i=1} m_i\deltaxi}
    \newcommand{\uppersum}[1][f]{U(#1,P) = \sum^n_{i=1} M_i\deltaxi}

%% Convenience Wrappers %%

    \newcommand{\hint}[1]{
        \begin{tcolorbox}[title=Hint]
            #1
        \end{tcolorbox}
    }

%% Document Setup %%

    \makeatletter
    \let\Title\@title
    \let\Author\@author
    \let\Date\@date
    \makeatother
    
%% \usepackage{graphicx, svg} %%

    \graphicspath{{images/}}
    \svgpath{{images/}}

%% \usepackage{fancyhdr} %%

    \pagestyle{fancy}
    \setlength{\headheight}{25pt}
    \lhead{\Title}
    \rhead{\Author}

%% \usepackage{hyperref} %%

    \hypersetup{
        pdfauthor={\Author},
        pdftitle={\Title},
        linktoc={all}
    }

%% \usepackage{titlesec} %%

    \titleformat{\subsection} % command
        [runin] % shape
        {\normalfont\bfseries} % format
        {\thesubsection} % label
        {1em} % sep
        {}
        
    \titleformat{\subsubsection} % command
        [runin] % shape
        {\normalfont\bfseries} % format
        {\thesubsubsection} % label
        {1em} % sep
        {}
        
%% Spacing/Formatting %%

    \setstretch{1.3}
    \newcommand{\resetpar}{
        \setlength{\parskip}{0.5em}
    }

%% tcolorbox Environments %%

    \renewenvironment{proof}
        {{\sffamily\bfseries Proof. }\resetpar}
        {\qed}

    \tcbset{
        boxrule=0pt,
        sharp corners,
        enhanced jigsaw,
        drop fuzzy shadow,
        breakable
    }
    
    \newtcolorbox{answer}{
        beforeafter skip balanced=25pt,
        colback={White!90!CornflowerBlue},
        borderline west={3pt}{0pt}{NavyBlue!80!white}
    }
        
    \tcolorboxenvironment{proof}{
        beforeafter skip balanced=25pt,
        colback={White!90!CornflowerBlue},
        borderline west={3pt}{0pt}{NavyBlue!80!white}
    }
    
%% Show code and output %%
%% (From: https://tex.stackexchange.com/questions/194854/how-to-show-latex-commands-in-text-mode/392818) %%

    \newcommand{\gfcb}[1]{%
        \fcolorbox{white}{gray!10!}{\quad\strut #1\quad}
        } % gfcb := gray fcolorbox
        
    \newcommand{\cop}[1]{%
        \gfcb{\texttt{\detokenize{#1}}} 
        \ensuremath{\quad \longrightarrow \quad & #1}
        } % cop := code output