html {
    position: relative;
    min-height: 100%;
}

body {
     background: url('../pics/orig_371441.jpg') no-repeat center fixed;
      -webkit-background-size: cover; /* pour anciens Chrome et Safari */
      background-size: cover; /* version standardisée */
    /* Margin bottom by footer height */
    margin-bottom: 100px;
}

h2 {
    font-size: 1.5rem;
    color: #214fa2;
    margin-top: 25px;
}

.panneau {
    border: 1px solid #ced4da;
    border-radius: .25rem;
    padding: 15px;
    background-color: #ffffff;
    width: 100%;
    max-width: 600px;
    margin: auto;
}

.footer {
    position: absolute;
    bottom: 0;
    width: 100%;
    /* Set the fixed height of the footer here */
    height: 60px;
    line-height: 60px; /* Vertically center the text there */
}

@media (max-width: 510px) {
    .panneau {
        padding: 5px;
    }
}