h1, h3, h4 {
    text-align: center
    }
h1 {
    font-size: larger;
    margin-top: 3em;
    margin-bottom: 1.5em
    }
h1.title {
    font-size: x-large;
    margin-top: 3em;
    margin-bottom: 1.5em
    }
h3.author {
    font-size: large;
    margin-top: 2em;
    margin-bottom: 1.5em
    }
h4.date {
    margin-bottom: 2em
    }