*{box-sizing:border-box}
body{margin:0;background:#fff;color:#000;font:16px/1.6 -apple-system,BlinkMacSystemFont,"Helvetica Neue",Arial,sans-serif;padding:0 16px}
main{max-width:680px;margin:0 auto;padding:40px 0 64px}
h1{font-size:28px;margin:0 0 4px}
h2{font-size:18px;margin:32px 0 8px}
.sub{color:#555;font-size:14px;margin:0 0 24px}
.box{border:1px solid #000;padding:12px 16px}
a{color:#000}
footer{margin-top:40px;font-size:14px}