body {
    min-width: 20em;
    max-width: 50em;
    margin: 0 auto;
    font-family: "Bitstream Vera Serif",  Georgia, serif;
}

#header { margin-top: 0.5em; height: 1.5em; }
#footer { margin: 2em 0; }
#header, #header a:link, #header a:visited, #footer {
    color: gray;
    font-family: "Bitstream Vera Sans",  Verdana, sans-serif;
}
#header a:hover { color: black }

h1, h2, h3, h4, h5, h6 {
    line-height: 1.4em;
    text-align: left;
    font-family: "Bitstream Vera Sans",  Verdana, sans-serif;
}

li {
    margin: 0.3em 0
}

pre, code { background-color: #eee; border: 1px solid #ccc; }
pre { padding: 0.3em; }
code { padding: 0 0.1em; }
pre > code { border: none; padding: 0; }

img {
    display: block;
    margin-left: auto;
    margin-right: auto;
}

img.left {
    float: left;
    margin: 2em;
    clear: both;
}

img.right {
    float: right;
    margin: 2em;
    clear: both;
}

p.center {
  text-align: center;
}