body{margin:0;background:#f6f7f9;color:#263244;font:17px/1.7 system-ui,sans-serif}header,main,footer{max-width:760px;margin:auto;padding:24px}header{border-bottom:1px solid #d9dee5}nav a{margin-right:20px;color:#315c8d}h1{font-size:28px}main{min-height:45vh}footer{color:#657184;font-size:14px}