body {
    background-color: blue;
}

h1 {
    text-align: center;
    color: white;
}

div {
    max-width: 300px;
    margin: auto;
    border: 3px solid #0000FF;
}

.center {
    margin-left: auto;
    margin-right: auto;
}

.white {
    color: white;
}