body 
{
margin:20px;
Text-align:left;
font-family: Arial, Helvetica, Geneva, Swiss, sans-serif;
}

h1
{
font-weight:bold;
text-align:center;
}

h2
{
font-weight:bold;
text-align:center;
}

article
{
font-weight:bold;
}

h3
{
font-weight:bold;
font-size:180%;
}

nav
{
text-align:right;
}

pre
{
font-size:100%;
font-family: Arial, Helvetica, Geneva, Swiss, sans-serif;
}

h4
{
font-size:110%;
}

footer
{
text-align:center;
}