body        { max-width: 40em;
              margin: auto;
            }
img         { max-width: 100%; }

nav         { border-bottom: 1px dotted black; }
nav a       { color: black;
              text-decoration: none;
              padding: 5px;
            }
nav a:hover { text-decoration: underline; }

h1          { font-family: arial; }