* { box-sizing: border-box; }
body { margin: 0; background: #f4f8fa; color: #172033; font: 17px/1.7 system-ui, sans-serif; }
header, main, nav { max-width: 900px; margin: auto; padding: 28px; }
main { background: white; border-radius: 18px; border: 1px solid #dce5eb; }
h1 { line-height: 1.2; font-size: clamp(1.8rem, 5vw, 2.5rem); }
h2 { font-size: 1.2rem; margin-top: 2rem; }
a { color: #09675f; text-underline-offset: 3px; overflow-wrap: anywhere; }
a:focus-visible { outline: 3px solid #f97316; outline-offset: 4px; }
.version { color: #59677b; }
nav { display: flex; flex-wrap: wrap; gap: 18px; }
nav [aria-current] { font-weight: bold; }
@media (max-width: 600px) { header, main, nav { padding: 20px; } }