\documentclass[a4paper, 10pt]{article}

\usepackage[margin=0.5in]{geometry}
\usepackage[colorlinks=true]{hyperref}
\usepackage{longtable}
\usepackage{booktabs}

\usepackage{fontspec}
\setmainfont[
	Path = fonts/,
	Extension = .ttf,
	UprightFont = *-Regular,
	ItalicFont = *-Italic,
	BoldFont = *-Bold,
	BoldItalicFont = *-BoldItalic
]{Arvo}

\setsansfont[
	Path = fonts/,
	Extension = .ttf,
	UprightFont = *-Regular,
	ItalicFont = *-Italic,
	BoldFont = *-Bold,
	BoldItalicFont = *-BoldItalic
]{Lato}

\usepackage{enumitem}
\setlist[itemize]{leftmargin=*}

\usepackage{parskip}
\setlength{\parindent}{0em}
\setlength{\parskip}{0.5em}
\setcounter{secnumdepth}{-1}

\def\tightlist{}
\usepackage{ulem}

\usepackage{titlesec}
\titleformat{\section}[hang]{\normalfont\Large}{\thesection}{1em}{}[{\titlerule[0.8pt]}]
\titleformat{\subsection}[hang]{\normalfont\normalsize\bfseries}{\thesubsection}{1em}{}
\titleformat{\subsubsection}[hang]{\normalfont\normalsize\itshape}{\thesubsubsection}{1em}{}

\titlespacing\section{0pt}{12pt plus 4pt minus 2pt}{6pt plus 2pt minus 2pt}
\titlespacing\subsection{0pt}{8pt plus 4pt minus 2pt}{4pt plus 2pt minus 2pt}
\titlespacing\subsubsection{0pt}{6pt plus 4pt minus 2pt}{4pt plus 2pt minus 2pt}
 \setlength{\LTleft}{0pt}
\begin{document}
$body$
\end{document}