Did you remove the bypass I did with CSS before testing ? because on my side and 2 other computer, private browsing or with cache clear still not working.
I will but it back since there is clearly an issue with static block and wait you can fix this…
Bypass i did that should not be done if everything works
footer.main-footer.main-footer-2.text-color-dark{
background-image: url(http://gmd.3ejoueur.com/wp-content/uploads/2015/06/footer.png);
background-color: rgba(0, 0, 0, 0);
background-size: cover;
background-repeat: repeat;
}