html {
    display: table;
    width: 100%;
    height: 100%;
}

body {
    display: table-cell;
    text-align: center;
    vertical-align: middle;
}

form span.label {
    display: inline-block;
    min-width: 10em;
    text-align: right;
}

form input[type="button"],[type="file"],[type="password"],[type="reset"],[type="submit"],[type="text"],[type="email"] {
    min-width: 20em;
}

form * {
    margin: .25em .5em;
}