html { font-size: 100%; }
body { font-size: 1.2rem;
       font-family: 'Helvetica Neue', Verdana, Helvetica, sans-serif;
       font-weight: 100; margin: 0; }
h1 { font-size: 2.5rem; }
h2 { border-bottom: 1px dotted; }

img { width: 100%;  max-width: 600px; }

code { font-size: 1.5em; }
pre { padding-left: 0; }
pre code { font-size: 1.2rem; }

.warning { padding: 5px 10px; border-left: solid 10px #b22222;
           background-color: #FFC6A6; }