body {
    margin-top: 1em;
    margin-bottom: auto;
    font-family: Arial, sans-serif;
}

h1 {
    text-align: center;
    font-size: 2.5em;
}

h2 {
    text-align: center;
    font-size: 2em;
}

nav {
    text-align: center;
}
p, div {
    margin: 10px;
    padding: 20px;
    line-height: 1.5em;
    text-align: center;
}

footer {
    text-align: center;
}

iframe {
    border: none;
}