#fondhtml
{
    background: linear-gradient( rgba(0, 0, 0, 0.45), rgba(0, 0, 0, 0.45) ),url("../images/fond_gray.jpg");
    background-size: cover;
}
.adminfond
{
    background: linear-gradient( rgba(0, 0, 0, 0.45), rgba(0, 0, 0, 0.45) ),url("../images/fond_bleu.jpg");
    background-size: cover;
}