.alert {
    position: fixed;
    z-index: 20;
    left: 50%; top: 20px;
    width: 520px;
    margin-left: -260px;
    background: #444;
    padding: 20px;
    border-radius: 2px;
    box-shadow: 0 20px 50px rgba(0,0,0,.2);
}