:root {
  color-scheme: light dark;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
  background: #f6f7f8;
  color: #17212b;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; }
a { color: #175e91; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible { outline: 3px solid #7bb8dd; outline-offset: 3px; border-radius: 2px; }

.skip-link {
  position: absolute;
  top: -4rem;
  left: 1rem;
  padding: .5rem .75rem;
  background: #fff;
  z-index: 2;
}
.skip-link:focus { top: .75rem; }

.site-header {
  border-bottom: 1px solid #d9e0e5;
  background: #fff;
}
.header-inner, .site-footer, main { max-width: 950px; margin: auto; }
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem;
}
.brand { font-weight: 750; font-size: 1.1rem; color: inherit; text-decoration: none; }
nav { display: flex; flex-wrap: wrap; gap: .75rem 1.25rem; }
nav a[aria-current="page"] { font-weight: 700; text-decoration-thickness: 2px; }

main { padding: 2.5rem 1.25rem 4rem; }
.eyebrow { margin: 0 0 .25rem; color: #526575; font-weight: 650; letter-spacing: .06em; text-transform: uppercase; font-size: .78rem; }
h1 { font-size: clamp(2rem, 5vw, 3rem); line-height: 1.15; margin: 0 0 .6rem; }
.updated { color: #526575; margin-top: 0; }
.intro { font-size: 1.08rem; max-width: 72ch; }
.notice {
  background: #eaf4f9;
  border-inline-start: 4px solid #2479a5;
  padding: .8rem 1rem;
  margin: 1.75rem 0;
}
.layout { display: grid; grid-template-columns: 210px minmax(0, 1fr); gap: 2rem; align-items: start; }
.toc { position: sticky; top: 1.5rem; border: 1px solid #d9e0e5; border-radius: 14px; padding: 1rem; background: #fff; }
.toc strong { display: block; margin-bottom: .5rem; }
.toc ol { margin: 0; padding-inline-start: 1.25rem; }
.toc li + li { margin-top: .35rem; }
.content section { padding-top: .25rem; margin-bottom: 2rem; }
h2 { font-size: 1.35rem; line-height: 1.3; margin: 0 0 .7rem; }
h3 { font-size: 1.05rem; margin: 1.25rem 0 .35rem; }
p, ul { margin: .65rem 0 1rem; }
li + li { margin-top: .4rem; }
.site-footer { border-top: 1px solid #d9e0e5; padding: 1.5rem 1.25rem 2rem; color: #526575; }
.site-footer p { margin: 0; }
.site-footer { display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }
.brand { display: inline-flex; align-items: center; gap: .5rem; }
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 1.75rem;
  height: 1.75rem;
  border: 2px solid currentColor;
  border-radius: 50%;
  font-size: .9rem;
  font-weight: 800;
}
.hero {
  border-radius: 26px;
  padding: clamp(2rem, 7vw, 4.5rem);
  background: linear-gradient(135deg, #dceaf2, #eef4ef);
  border: 1px solid #d9e0e5;
}
.hero h1 { max-width: 15ch; font-size: clamp(2.5rem, 8vw, 5rem); }
.hero > p:not(.eyebrow) { max-width: 58ch; font-size: 1.1rem; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.5rem; margin-top: 1.75rem; }
.button {
  display: inline-block;
  border-radius: 12px;
  background: #175e91;
  color: #fff;
  font-weight: 700;
  padding: .75rem 1.2rem;
  text-decoration: none;
}
.button:hover { background: #104d78; }
.text-link { font-weight: 650; }
.features { padding: 4rem 0 2rem; }
.section-heading { max-width: 58ch; margin-bottom: 1.75rem; }
.section-heading h2, .home-note h2 { font-size: clamp(1.7rem, 4vw, 2.3rem); }
.feature-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.feature-card { border: 1px solid #d9e0e5; background: #fff; border-radius: 18px; padding: 1.5rem; }
.feature-card h3 { margin-top: .75rem; }
.feature-card p { margin-bottom: 0; }
.feature-number { font-size: .8rem; font-weight: 750; color: #526575; }
.home-note {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  align-items: center;
  border-top: 1px solid #d9e0e5;
  padding: 2.5rem 0 0;
}
.home-note p:last-child { margin: 0; }
.faq { margin-top: 3.5rem; }
.faq-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.faq .feature-card h3 { margin-top: 0; }
.support-note { border-top: 1px solid #d9e0e5; margin-top: 2.5rem; padding-top: 2rem; }

@media (max-width: 720px) {
  main { padding-top: 2rem; }
  .layout { display: block; }
  .toc { position: static; margin: 1.5rem 0 2rem; }
  .feature-grid, .home-note, .faq-grid { grid-template-columns: 1fr; }
  .header-inner { align-items: flex-start; flex-direction: column; }
}

@media (prefers-color-scheme: dark) {
  :root { background: #111920; color: #e9eff3; }
  a { color: #92cffa; }
  .site-header, .toc { background: #18242e; border-color: #364653; }
  .updated, .eyebrow, .site-footer { color: #a8bac8; }
  .notice { background: #193344; border-color: #7bb8dd; }
  .site-footer { border-color: #364653; }
  .skip-link { background: #18242e; }
  .hero { background: linear-gradient(135deg, #193344, #1d302d); border-color: #364653; }
  .feature-card { background: #18242e; border-color: #364653; }
  .feature-number { color: #a8bac8; }
  .home-note, .support-note { border-color: #364653; }
}

@media print {
  :root { background: #fff; color: #000; }
  nav, .toc, .skip-link { display: none; }
  main { max-width: none; padding: 0; }
  .layout { display: block; }
  section { break-inside: avoid; }
  a { color: inherit; }
}