style.css

body {
        font: .8em "Trebuchet MS", Verdana, Arial, Sans-Serif;
        background: url('http://m.b4n.fr/gris_190.jpg');
        color: #80679d;
        text-align: center;
        margin-top: 5em;
}

h1 {
        font-size: 2em;
        padding: 0;
        margin: 0;
}

h4 {
        font-size: 1em;
        font-weight: bold;
}

form {
        width: 28em;
        background-color: #eee;
        border: 1px solid #ccc;
        margin-left: auto;
        margin-right: auto;
        padding: 1em;
}

fieldset {
        border: 0;
        margin: 0;
        padding: 0;
}

a {
        color: #573ae5;
        text-decoration: none;
        font-weight: bold;
}

a:visited {
        color: #80427b;
        text-decoration: none;
}

a:hover {
        text-decoration: underline;
}

.error, .success {
        font-size: 1.2em;
        font-weight: bold;
}

.error {
        color: #de82c5;
}

.success {
        color: #9978e5;
}