body{margin:0;font:17px/1.6 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;background:#fff;color:#222}
main{max-width:520px;margin:0 auto;padding:48px 20px}
h1{font-size:28px;margin:0 0 12px}
a{color:#0070a8}
.pre{white-space:pre-line}