It is possible to make a full bg-img with fullPage.js?

this is possible to have a single background-img for all my section with FullPage.js?

Actually I have my img in the background of all my section, but I want one big and same img for all my body.

there is a part of my code:

echo '<div id="fullPage">';
while ($row = $stmt->fetch()){
    echo '<div class="section">
        <img id="'.$row['id'].'" class="anim photo" data-delay=".2s" src="'.$row['url'].'">
        <p class="anim_commentaire commentaire" data-delay=".4s">'.$row['description'].'</p>
    </div>';
}

echo '<div>';

for have a lot a <div class="section"> in a fullPage div.

$(".section").addClass("clouds);

to add a class at all my section

.clouds{
    background-image: url(https://live.staticflickr.com/3170/2807971606_cfa2a3d3a2_z.jpg);
}

to have my background-image.

The probleme is I have a background in all my <div class="section"> but I want to have a big background <div id="fullPage">,

#fullPage{
    background-image: url(https://live.staticflickr.com/3170/2807971606_cfa2a3d3a2_z.jpg);
}
``` doesn't work.