h1, h2, h3, h4, p, li {font-family: Avenir, Helvetica, Arial, sans-serif;}
h1 {font-size: 300%; font-weight: 800; margin: 50px 0;}
h2 {font-size: 250%; font-weight: 600;}
h3 {font-size: 200%; font-weight: 500;}
h4 {font-size: 150%; font-weight: 400;}
h5 {font-size: 100%;}


.nav-link {font-weight: bold;}
.nav-link:link, .nav-link:visited {color: silver;}
.nav-link:hover, .nav-link:active {color: white;}

header {text-align: center;}
footer {padding: 50px; margin-top: 50px; border-top: 1px solid black; text-align: center;}