:root {
  color-scheme: light;
  --ink: #101418;
  --muted: #5d6670;
  --line: #dfe5e8;
  --surface: #f5f8f7;
  --accent: #117a65;
  --accent-dark: #0b5c4c;
  --max: 920px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}
a { color: inherit; }
a:focus-visible, button:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .85rem max(1.25rem, calc((100vw - var(--max)) / 2));
  border-bottom: 1px solid rgba(223,229,232,.88);
  background: rgba(255,255,255,.95);
  backdrop-filter: blur(12px);
}
.brand { font-size: 1.3rem; font-weight: 850; text-decoration: none; letter-spacing: -.03em; }
nav { display: flex; gap: .9rem; }
nav a { text-decoration: none; font-weight: 700; color: var(--muted); }
nav a:hover, nav a:focus-visible { color: var(--accent); }
main, footer { width: min(var(--max), calc(100% - 2.5rem)); margin-inline: auto; }
.hero { min-height: auto; display: grid; align-content: center; padding: 4rem 0 3.5rem; border-bottom: 1px solid var(--line); }
.eyebrow { margin: 0 0 .7rem; color: var(--accent); font-size: .8rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
h1, h2, h3 { line-height: 1.18; margin-top: 0; overflow-wrap: anywhere; }
h1 { max-width: 820px; margin-bottom: 1.25rem; font-size: clamp(2.35rem, 6vw, 4.25rem); letter-spacing: -.045em; }
h2 { margin-bottom: .9rem; font-size: clamp(1.55rem, 3.6vw, 2.25rem); letter-spacing: -.025em; }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.55rem); }
.lead, .section-copy { max-width: 820px; color: var(--muted); }
.lead { margin: 0; font-size: clamp(1.02rem, 2vw, 1.25rem); }
.actions { display: grid; grid-template-columns: 1fr; gap: .7rem; margin-top: 1.5rem; }
.button { display: inline-flex; align-items: center; justify-content: center; width: 100%; min-height: 48px; padding: .75rem 1rem; border: 1px solid var(--ink); border-radius: 18px; text-decoration: none; text-align: center; font-weight: 750; }
.button.primary { color: #fff; border-color: var(--accent); background: var(--accent); }
.button.primary:hover { background: var(--accent-dark); }
.button.secondary:hover { background: var(--surface); }
.section { padding: 3.75rem 0; }
.section-heading { max-width: 820px; }
.chapter-grid, .principle-grid { display: grid; grid-template-columns: 1fr; gap: .85rem; margin-top: 1.5rem; }
.chapter-card { display: grid; grid-template-columns: 1fr; row-gap: .55rem; min-height: auto; padding: 1.2rem; border: 1px solid var(--line); border-radius: 20px; text-decoration: none; background: #fff; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease; overflow-wrap: anywhere; }
.chapter-card:hover, .chapter-card:focus-visible { transform: translateY(-1px); border-color: #b9c8c5; box-shadow: 0 10px 28px rgba(16,20,24,.05); }
.chapter-id { display: inline-grid; width: fit-content; max-width: 100%; min-width: 2.6rem; min-height: 2.6rem; padding: .35rem .7rem; place-items: center; border-radius: 999px; color: #fff; background: var(--accent); font-weight: 850; overflow-wrap: anywhere; }
.chapter-card strong { display: block; font-size: 1.12rem; }
.chapter-card small { display: block; color: var(--muted); font-size: .95rem; line-height: 1.55; }
.stacked-grid .chapter-card { grid-template-columns: 1fr; align-content: start; row-gap: .7rem; }
.stacked-grid .chapter-card strong, .stacked-grid .chapter-card small { display: block; }
.title-line { display: block; }
.panel { margin-bottom: 1rem; padding: 2rem clamp(1rem, 3vw, 2rem); border-radius: 22px; background: var(--surface); }
.principle-grid > div { padding: 1.15rem; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.principle-grid p { margin-bottom: 0; color: var(--muted); }
.status-section { border-top: 1px solid var(--line); }
.status { display: inline-flex; align-items: center; gap: .55rem; margin-top: 1rem; padding: .65rem .9rem; border: 1px solid var(--line); border-radius: 999px; background: #fff; }
.status-dot { width: .65rem; height: .65rem; border-radius: 50%; background: var(--accent); }
footer { display: flex; flex-direction: column; gap: .5rem; padding: 2rem 0 3rem; border-top: 1px solid var(--line); color: var(--muted); }
footer p { margin: 0; }

@media (max-width: 760px) {
  main, footer { width: min(var(--max), calc(100% - 1.5rem)); }
  .site-header { position: sticky; display: flex; align-items: center; gap: .6rem; padding: .55rem max(.75rem, env(safe-area-inset-right)) .55rem max(.75rem, env(safe-area-inset-left)); }
  .brand { flex: 0 0 auto; min-height: 44px; display: inline-flex; align-items: center; }
  .site-header nav { display: flex; flex: 1 1 auto; gap: .35rem; min-width: 0; overflow-x: auto; overflow-y: hidden; padding: .1rem .75rem .25rem 0; scrollbar-width: thin; scroll-snap-type: x proximity; overscroll-behavior-inline: contain; -webkit-overflow-scrolling: touch; mask-image: linear-gradient(to right, #000 0, #000 calc(100% - 1rem), transparent 100%); }
  .site-header nav a { flex: 0 0 auto; display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: .5rem .7rem; border: 1px solid var(--line); border-radius: 12px; white-space: nowrap; text-align: center; font-size: .84rem; line-height: 1.2; scroll-snap-align: start; }
  .site-header nav a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
  .hero { padding: 2.75rem 0 2.5rem; }
  h1 { font-size: clamp(2rem, 10vw, 3rem); }
  h2 { font-size: clamp(1.45rem, 7vw, 2rem); }
  .section { padding: 2.75rem 0; }
  .panel { padding: 1.25rem 1rem; border-radius: 18px; }
  .chapter-card { padding: 1rem; border-radius: 16px; }
  .button { border-radius: 16px; }
}

@media (max-width: 420px) {
  .site-header { gap: .45rem; }
  .site-header nav a { padding-inline: .6rem; font-size: .8rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
  .chapter-card:hover, .chapter-card:focus-visible { transform: none; }
}