\usepackage[left=1.5cm,right=1.7cm,
top=1.57cm,bottom=2.3cm]{geometry}
\usepackage[svgnames,dvipsnames,x11names,]{xcolor}
\usepackage{url}
\usepackage{hyperref}
%\usepackage[pages=all]{background}
\hypersetup{pdfstartview=FitH,colorlinks=true, linkcolor=black, urlcolor=green!50!black}
\usepackage[explicit]{titlesec}
\usepackage{varwidth}
\usepackage[listings]{tcolorbox}
\usepackage{esvect}
\usepackage{tcolorbox, graphicx,  tikz}
\usepackage{graphicx}
\usepackage{svgcolor}
\usepackage[utf8]{inputenc}
\usepackage{esvect}
\usepackage{na-border}
\usepackage{contour}
\usepackage{fancybox}
\usepackage{bidicontour}
\usepackage{amsmath,amsfonts,amssymb,mathrsfs} 
\usepackage{fancyhdr}
\usepackage{xkeyval}
\usepackage{tikzpagenodes}
\usetikzlibrary{shadows,calc,backgrounds}
\usepackage{contour}
\usepackage{pgf ,tikz}
\usepackage{pifont}
\usetikzlibrary{decorations.pathmorphing}
\tcbuselibrary{skins,breakable}
\usetikzlibrary{decorations, decorations.text}
\usetikzlibrary{calc}
\tcbuselibrary{listings}
\usetikzlibrary{decorations.pathmorphing}
\tcbuselibrary{listings,breakable,skins}
\usetikzlibrary{patterns}
\usetikzlibrary{shapes,shadings,shadows,shapes.geometric,decorations,positioning,arrows,decorations.pathmorphing}
\usetikzlibrary{calc,fadings,shapes.geometric,shapes.misc, decorations.pathmorphing,shadows}
\usetikzlibrary{calc,intersections} 
\usepackage{listings}