Sidebar pushes the contents - Wordpress

Hello,

Sue this site: http://www.workinprogress.blfacademie.be/

I put a sidebar with button that pushes the contents of the website

For this in the code below I put the different parts of the site in sections

<style>
/* The side navigation menu */
.sidenav2 {
    height: 100%; /* 100% Full-height */
    width: 0; /* 0 width - change this with JavaScript */
    position: fixed; /* Stay in place */
    z-index: 1; /* Stay on top */
    top: 0;
    right: 0;
    background-color: #ffffff; /* Black*/
    overflow-x: hidden; /* Disable horizontal scroll */
    padding-top: 60px; /* Place content 60px from the top */
    transition: 0.5s; /* 0.5 second transition effect to slide in the sidenav */
    border-left: 1px solid #E5E5E5;
}


/* The navigation menu links */
.sidenav2 a {
/*padding: 8px 8px 8px 32px;*/
    text-decoration: none;
    font-size: 13px;
    color: #343434;
    display: block;
    transition: 0.3s;
    text-indent: -13px;
    padding-left: 10px;
}


/* When you mouse over the navigation links, change their color */
.sidenav2 a:hover, .offcanvas a:focus{
    color: #818181;
}


.sidenav2 a:before {
    content: "•"; 
    padding-right: 8px;
/*color: #9e0e0e;*/
}


/* Position and style the close button (top right corner) */
.sidenav2 .closebtn2 {
    position: absolute;
    top: -4px;
    right: 12px;
    font-size: 36px;
    margin-left: 50px;
}


/* Style page content - use this if you want to push the page content to the right when you open the side navigation */
#main2 {
    transition: margin-right .5s;
}


/* On smaller screens, where height is less than 450px, change the style of the sidenav (less padding and a smaller font size) */
@media screen and (max-height: 450px) {
    .sidenav2 {padding-top: 15px;}
    .sidenav2 a {font-size: 18px;}
}



title { 
    display:block !important;
    color: #9e0e0e;
    text-align: center;
    border-bottom: 1px solid;
    margin-top: 20px;
    margin-bottom: 10px;
}
</style>


<script>


/* Set the width of the side navigation to 250px and the left margin of the page content to 250px and add a black background color to body */
function openNav2() {
    document.getElementById("mySidenav2").style.width = "250px";
    document.getElementById("mySidenav2").style.left = "inherit";
    document.getElementById("section3").style.marginRight = "250px";
    document.getElementById("section6").style.marginRight = "250px";
    document.getElementById("section2").style.marginRight = "250px";
    document.body.style.backgroundColor = "rgba(0,0,0,0.4)";
}


/* Set the width of the side navigation to 0 and the left margin of the page content to 0, and the background color of body to white */
function closeNav2() {
    document.getElementById("mySidenav2").style.width = "0";
    document.getElementById("section3").style.marginRight = "0";
    document.getElementById("section6").style.marginRight = "0";
    document.getElementById("section2").style.marginRight = "0";
    document.body.style.backgroundColor = "white";
}


</script>


<div id="mySidenav2" class="sidenav2">
  <a href="javascript:void(0)" class="closebtn2" onclick="closeNav2()">&times;</a>
  <br />
  <div style="padding:0 20px;color:#343434;">
    <center><?php
    // afficher photo user
    $user = wp_get_current_user()->ID;
    $size = 100;
    echo get_avatar( $user, $size );
      ?></center>
    <br />
    <strong>
    <?php
    $current_user = wp_get_current_user();
    echo 'Bonjour ' . $current_user->display_name . '<br /><br />';
    ?>
    </strong>


    <?php dynamic_sidebar('area-3-widget-area'); ?>
  </div>
</div>


<!-- Use any element to open the sidenav -->
<span onclick="openNav2()"><a href="#"><?php
                $current_user = wp_get_current_user();
                echo 'Bonjour ' . $current_user->display_name . '&nbsp;';
                // afficher photo user
                $user = wp_get_current_user()->ID;
                $size = 30;
                echo get_avatar( $user, $size );
              ?>
  </a></span>

This works on the home page but not on the other pages while the sections have the same ID.

Can you help me please ?