:root{background-color:#fff;font-family:sans-serif}html,body{margin:0;padding:0}body{display:flex;flex-direction:column;min-height:100vh}nav{position:sticky;top:0}nav menu{justify-content:end;display:flex;flex-direction:row;gap:1rem;list-style:none;margin:0;padding:1rem;border-bottom:thin solid gray;background-color:#d3d3d3;font-family:sans}footer{background-color:#d3d3d3;padding:1rem;border-top:thin solid gray;font-family:sans;font-size:smaller}footer p{margin:0}section#body{flex-grow:1;padding:1rem}p.error{color:red}