\documentclass{article}
\usepackage[margin=1.5cm]{geometry}
\usepackage{tikz}
\usepackage{xcolor} % Required for color definitions
\usepackage{eso-pic} % Required for \AddToShipoutPictureBG
\usepackage{lipsum} % For dummy text
\usetikzlibrary{calc}
\usepackage{titletoc} % Required for customization of TOC


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%% tcolor boxes

\usepackage{tcolorbox}
\tcbuselibrary{skins}
\tcbuselibrary{breakable}

\newtcolorbox{myremark}[1]{%
    attach boxed title to top left={yshift=-2mm},
    coltitle=black,colbacktitle=red!45!white,enhanced,
    fonttitle=\bfseries,
    title=\large #1,
    colframe=red!75!black,
    colback=yellow!80,
}


\newtcolorbox{definition}[1]%
{ enhanced,arc=1mm,outer arc=1mm,
    attach boxed title to top left={yshift=-2mm},
    colframe=blue!50!black,colback=green!15!white,
    coltitle=blue!50!black,colbacktitle=yellow!50!white,
    fonttitle=\bfseries,
    title=\large #1,
}

\newtcolorbox{proposition}[1]%
{ enhanced,arc=1mm,outer arc=1mm,
    attach boxed title to top left={yshift=-2mm},
    colframe=red!80!blue,colback=blue!15!white,
    coltitle=green!80!blue,colbacktitle=red!30!white,
    title=\large\bfseries #1,
}

\newtcolorbox{myexample}[1]{%
    empty,
    attach boxed title to top left={yshift*=-\tcboxedtitleheight},
    title={\large\bfseries #1},
    boxed title style={
        overlay={
            \draw[green!70!blue,line width=2pt,] (frame.south west)--(frame.south east);
        },
        size=minimal, top=0pt, left=0pt
    },
    coltitle=red!10!blue,
}


\newcommand*\bdot{\tikz[baseline=(char.base)]{
        \node[shape=circle,fill=black,inner sep=1.5pt] (char) {};
}}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


\usepackage{setspace}


\usepackage{hyperref}
\hypersetup{
    colorlinks=true,
    linkcolor=black
}
\newcommand{\mylink}{\href{https://mosaid.xyz/cc}{www.mosaid.xyz}}
\newcommand{\mlink}{www.mosaid.xyz}

% Define the color
\definecolor{blueA}{RGB}{0, 128, 255} % Adjust the RGB values as needed
\author{MOSAID}
\newcommand{\myauthor}{MOSAID}
\title{Produit Scalaire dans l'espace}
\newcommand{\mytitle}{Produit Scalaire dans l'espace}
\newcommand{\myclass}{2ème Bac Science Ex}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%% the background rectangles

\pgfdeclareverticalshading{myvshading}{100bp}{
  color(0bp)=(blueA);
  color(100bp)=(red!20)
}

\pgfdeclarehorizontalshading{myhshading}{2cm}{
  color(0cm)=(red!70);
  color(2cm)=(blueA)
}

\AddToShipoutPictureBG{%
    \begin{tikzpicture}[remember picture,overlay]

      % top ribbon in first page
      \ifnum\value{page}=1
        \shade[shading=myhshading] ([yshift=-1.5cm]current page.north west) rectangle (current page.north east);
        \fill[blue] ([xshift=1cm]current page.north west) arc (-180:-90:1.5cm) -- ++(2.5cm,0)
        arc (-90:-180:2.5cm)  -- cycle;
        \node[white, align=center] at ([xshift=2.3cm,yshift=-.75cm]current page.north west) {\Huge\bfseries{09}};
        \node[white, align=center] at ([xshift=.5cm,yshift=-.75cm]current page.north)
          {\Huge\bfseries{\mytitle}};
      \fi

      % Left ribbon
      \shade[shading=myvshading] ([xshift=1cm, yshift=-3.50cm]current page.north west) rectangle ++(-10,-13);
      \node[align=center, white, rotate=90] at ([xshift=0.5cm, yshift=-10cm]current page.north west) {\huge\bfseries\mytitle};

      % Bottom ribbon
      \shade[shading=myhshading] ([yshift=1cm]current page.south west) rectangle (current page.south east);
      %\fill[blueA] ([yshift=1cm]current page.south west) rectangle (current page.south east);

      % Page number
      \node[circle,draw=white,line width=2pt,minimum size=0.3cm,fill=blueA,font=\bfseries\color{white}]
          at ([yshift=0.9cm]current page.south) {\thepage};

      \node[anchor=west] at ([yshift=0.75cm,xshift=1cm]current page.south west) {\textbf{\color{white}\myauthor}};

      \node[anchor=east] at ([xshift=-1.5cm,yshift=0.75cm]current page.south east) {\textbf{\textcolor{white}{\mylink}}};
      \node[anchor=east] at ([xshift=-1.5cm,yshift=0.75cm]current page.south east) {\textbf{\textcolor{white}{\mlink}}};
    \end{tikzpicture}
}

% Redefine \maketitle
\makeatletter
\renewcommand{\maketitle}{
        \vspace*{1cm}
        \begin{center}
            {\Huge\bfseries\color{blueA}\@title} \\[1cm]
            {\huge\bfseries\color{blueA!50!red}\myclass} \\[1cm]
            {\Large\color{red!75}\myauthor~ ~\mylink }\\[0.5cm]
            {\large\color{red!45}\today}
        \end{center}
}
\makeatother

% Define colors for section types
\definecolor{sectioncolor}{RGB}{255, 0, 0} % Red
\definecolor{subsectioncolor}{RGB}{0, 128, 0} % Green
\definecolor{subsubsectioncolor}{RGB}{0, 0, 255} % Blue

\renewcommand{\contentsname}{Contenu}
\pagestyle{empty}

\begin{document}
% Title page
\maketitle
% Table of Contents
\tableofcontents
\clearpage

\section{\textcolor{sectioncolor}{\lipsum[1][1-1]}}

\subsection{\textcolor{subsectioncolor}{\lipsum[2][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[3][1-1]}}
\begin{proposition}{proposition}
  \lipsum[1]
  \end{proposition}

  \begin{myexample}{exemple}
    \lipsum[1]
  \end{myexample}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[4][1-1]}}

\subsection{\textcolor{subsectioncolor}{\lipsum[5][1-1]}}

  \begin{definition}{definition}
    \lipsum[1]
  \end{definition}

  \begin{myremark}{remarque}
    \lipsum[1]
  \end{myremark}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[6][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[7][1-1]}}

\section{\textcolor{sectioncolor}{\lipsum[8][1-1]}}

\subsection{\textcolor{subsectioncolor}{\lipsum[9][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[10][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[11][1-1]}}

\subsection{\textcolor{subsectioncolor}{\lipsum[12][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[13][1-1]}}

\subsubsection{\textcolor{subsubsectioncolor}{\lipsum[14][1-1]}}

\end{document}