form.membres {
    background-image: url('../images/membres.jpg');
    background-image: url('https://fastly.picsum.photos/id/156/2177/3264.jpg?hmac=hjKWxNR5fYw1fbGYXknGDH6eRORZ_AlTeQBvyT2q_Cs');
    background-image: url('https://fastly.picsum.photos/id/103/2592/1936.jpg?hmac=aC1FT3vX9bCVMIT-KXjHLhP6vImAcsyGCH49vVkAjPQ');
    background-image: url('https://fastly.picsum.photos/id/65/4912/3264.jpg?hmac=uq0IxYtPIqRKinGruj45KcPPzxDjQvErcxyS1tn7bG0');
    background-image: url('https://fastly.picsum.photos/id/705/5000/3333.jpg?hmac=ClJCSRuDzMy9zl38ZL6VrbKsFxFNAKbeFFfHuEjStWE');
    background-image: url('https://fastly.picsum.photos/id/1010/5000/3333.jpg?hmac=CuwA5P9jjX0HXsLl6IzkF6a7YHmXujB7zLwbtdRPEyM');
    background-image: url('https://fastly.picsum.photos/id/881/3000/2000.jpg?hmac=H8KkMX3MzuVL5dd9JCnF5RhLPbJ7B5do_WY2zQ5zWMI');
    background-image: url('https://fastly.picsum.photos/id/830/5000/3333.jpg?hmac=oq5nqz20klOJ7ONdU-bEGtDBSEP5mqClKQBhgrxO4UQ');
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center top;
    height: 100vh;
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}
form.membres input[type=text],
form.membres input[type=password] {
    margin: 10px 0;
    width: 300px;
    padding: 10px;
    background: transparent;
    border: none; 
    border-bottom: dotted 1px #fff; 
}
form.membres input::placeholder {
    color: #fff;
}
form.membres input[type=submit] {
    color: #fff;
    border: dotted 1px #fff; 
    background: transparent;
    padding: 10px 25px;
    margin: 25px 0;
}