\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[french]{babel}
\usepackage[T1]{fontenc}
\usepackage{xcolor}
\usepackage{tikz}
\usetikzlibrary{calc}
\usepackage{anyfontsize}
%============================================
\definecolor{myblue3}{RGB}{36, 57, 126}
\definecolor{myblue4}{RGB}{81,91,199}
\definecolor{YankeesBlue}{RGB}{28,40,65}
\definecolor{mygray}{RGB}{112,121,139}
\definecolor{gold}{RGB}{252, 200, 3}
\definecolor{MainRed}{rgb}{.6, .1, .1}
\definecolor{mygray2}{RGB}{150,150,150}
\definecolor{mygreen}{RGB}{0,120,2}
\definecolor{winered}{rgb}{0.5,0,0}
%=================================================
\begin{document}
\pagestyle{empty}
\begin{tikzpicture}[remember picture,overlay]
\path
(current page.north west) coordinate (A)
(current page.north east) coordinate (B)
(current page.south east) coordinate (C)
(current page.south west) coordinate (D)
(current page.north) coordinate (A1)
(current page.east) coordinate (E)
(current page.west) coordinate (W);
%%%%%%%%%%%%%%%%%%%% Background %%%%%%%%%%%%%%%%%%%%%%%%
\coordinate (W1) at ([shift={(0,3)}]current page.west);
\coordinate (E1) at ([shift={(0,3)}]current page.east);
\coordinate (E2) at ([shift={(0,-3)}]current page.east);
\coordinate (F) at ($(W1)!0.4!(E1)$);
%========================================
\fill[mygray!30!white] (A) rectangle (C);
%===================================================
\fill[myblue3](A)--(F)--++(6,0)--++(0,-.75)--($(F)+(0,-.75)$)--($(W)+(0,9)$)--cycle;
\fill[winered]($(W)+(0,8)$)--($(F)+(0,-1)$)--++(6,0)--++(0,-.75)--($(F)+(0,-1.75)$)--($(W)+(0,4)$)--cycle;
\fill[mygreen]($(W)+(0,3)$)--($(F)+(0,-2)$)--++(6,0)--++(0,-.75)--($(F)+(0,-2.75)$)--($(W)+(0,-2)$)--cycle;
\fill[gold]($(W)+(0,-3)$)--($(F)+(0,-3)$)--(E)--++(0,-.75)--($(F)+(0,-3.75)$)--($(W)+(0,-7)$)--cycle;
\fill[cyan]($(W)+(0,-8)$)--($(F)+(0,-4)$)--($(E)+(0,-1)$)--++(0,-.75)--($(F)+(0,-4.75)$)--(D)--cycle;
%===================================================
\node[] at ($(E)+(-4,1.6)$)
{\color{myblue3} \fontsize{115}{115}\selectfont Bac};
%=============================================
\node[font=\bfseries\color{myblue3},text width=6cm,align=left] at ([shift={(-10,-3)}]E) { \fontsize{38}{38}\selectfont\uppercase{Mathématiques}};
%=============================================
\node[font=\bfseries\color{myblue3},text width=8cm,align=left] at ([shift={(-9,5)}]E) { \fontsize{25}{25}\selectfont\uppercase{Se préparer au}};
%=================================================
\node[white,rotate=-45] at ($(A)+(3,-6)$)
{\bfseries \fontsize{20}{20}\selectfont Suites numériques};
\node[white,rotate=-25] at ($(A)+(3.5,-10)$)
{\bfseries \fontsize{20}{20}\selectfont Fonctions logarithmes};
\node[white] at ($(A)+(4.5,-13.3)$)
{\bfseries \fontsize{20}{20}\selectfont Fonctions exponentielles};
\node[myblue3,rotate=30] at ($(A)+(3.5,-17)$)
{\bfseries \fontsize{20}{20}\selectfont Nombres complexes};
\node[white,rotate=48] at ($(A)+(3.5,-21)$)
{\bfseries \fontsize{20}{20}\selectfont Fonctions primitives};
\end{tikzpicture}
\end{document}