:root{color-scheme:dark light;font:18px/1.7 system-ui;background:light-dark(#f5f7f3,#101713);color:light-dark(#172a20,#eef4ed)}*{box-sizing:border-box}body{max-width:780px;margin:auto;padding:24px}header,nav{display:flex;gap:20px;flex-wrap:wrap}header{justify-content:space-between;align-items:center}header a{display:inline-flex;align-items:center;gap:8px}a{color:light-dark(#146943,#83dfaf);text-underline-offset:4px;padding:8px 0}a:focus-visible{outline:3px solid currentColor;outline-offset:3px}h1{font-size:clamp(2rem,6vw,3rem);line-height:1.15}p{margin:24px 0}.intro{font-size:1.2rem}.action{display:inline-block;padding:12px 18px;border:1px solid;border-radius:8px}footer{margin-top:48px}