body{margin:0;background:#faf9f6;color:#263238;font:18px/1.7 system-ui,sans-serif}main,header,footer{max-width:760px;margin:auto;padding:28px}header{border-bottom:1px solid #ddd}a{color:#245b63}h1{font-size:38px;line-height:1.2}h2{font-size:24px}article{margin:36px 0}footer{font-size:14px;color:#64716e;border-top:1px solid #ddd}.intro{color:#64716e}nav a{margin-right:20px}