:root {
  --paper: #f8f8f6;
  --surface: #fff;
  --ink: #202522;
  --muted: #69706c;
  --line: #d9ddda;
  --accent: #17663f;
  --danger: #963d32;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--paper); color: var(--ink); font-size: 16px; line-height: 1.5; }
main { width: min(880px, calc(100% - 40px)); margin: 0 auto; }
a { color: inherit; text-underline-offset: .18em; }
nav { min-height: 64px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); font-size: 14px; }
nav a { font-weight: 650; text-decoration: none; }
nav span, .quiet { color: var(--muted); font-size: 13px; }
.intro { max-width: 680px; padding: 48px 0 28px; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 10px; font-size: 32px; line-height: 1.2; letter-spacing: -.02em; }
.intro p { margin-bottom: 0; color: var(--muted); font-size: 17px; }
.server-status { padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.server-status h2 { margin-bottom: 5px; font-size: 15px; }
.server-status p { margin-bottom: 0; color: var(--muted); }
.server-status.online h2 { color: var(--accent); }
.server-status.offline h2 { color: var(--danger); }
.server-status a { color: var(--accent); }
.section { padding: 38px 0; border-bottom: 1px solid var(--line); }
.section > h2, .section-heading h2 { margin-bottom: 18px; font-size: 19px; }
.section-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 20px; }
.text-button { padding: 0; border: 0; background: transparent; color: var(--accent); font: inherit; font-size: 13px; cursor: pointer; }
.text-button:hover { text-decoration: underline; }
.walkthrough { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.walkthrough li { display: grid; grid-template-columns: 92px 1fr; gap: 16px; padding: 13px 0; border-bottom: 1px solid var(--line); opacity: .35; }
.walkthrough li.visible { opacity: 1; }
.walkthrough span { color: var(--muted); font-size: 13px; font-weight: 600; }
.walkthrough p { margin: 0; }
.walkthrough + .quiet { margin: 10px 0 0; }
.architecture { display: grid; grid-template-columns: 1fr auto 1.35fr auto 1fr; align-items: center; gap: 12px; }
.architecture-node { min-height: 132px; display: flex; flex-direction: column; justify-content: center; padding: 16px; border: 1px solid var(--line); background: var(--surface); }
.architecture-node.emphasis { border-color: #9eb6a7; }
.architecture-node strong { margin-bottom: 6px; font-size: 14px; }
.architecture-node span { color: var(--muted); font-size: 13px; }
.architecture-node small { margin-top: 14px; color: var(--muted); font-size: 11px; }
.architecture-arrow { color: var(--muted); }
.architecture-note { max-width: 720px; margin: 16px 0 0; color: var(--muted); font-size: 13px; }
.live-demo > p { max-width: 680px; color: var(--muted); }
form { display: grid; gap: 18px; max-width: 680px; margin-top: 22px; }
.unlock-form { grid-template-columns: minmax(0, 1fr) auto; align-items: end; }
.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
label { display: grid; gap: 6px; font-size: 13px; font-weight: 600; }
input, textarea { width: 100%; padding: 11px 12px; border: 1px solid #c9cecb; border-radius: 5px; background: #fff; color: var(--ink); font: inherit; font-weight: 400; }
input:focus, textarea:focus, button:focus-visible, a:focus-visible { outline: 2px solid rgba(23, 102, 63, .35); outline-offset: 2px; }
button { padding: 11px 14px; border: 0; border-radius: 5px; background: var(--ink); color: #fff; font: inherit; font-weight: 600; cursor: pointer; }
button:hover { background: #353b37; }
.secondary { border: 1px solid var(--line); background: transparent; color: var(--ink); }
.error { min-height: 20px; margin: 0; color: var(--danger); font-size: 13px; }
.unlock-form .error { grid-column: 1 / -1; }
.active-call { max-width: 680px; margin-top: 22px; }
.active-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 20px; }
.active-heading h3 { font-size: 18px; }
.active-heading span { color: var(--accent); font-size: 13px; font-weight: 600; }
#active-objective { color: var(--muted); }
.transcript { margin: 18px 0; border-top: 1px solid var(--line); }
.turn { display: grid; grid-template-columns: 88px 1fr; gap: 14px; padding: 11px 0; border-bottom: 1px solid var(--line); font-size: 14px; }
.turn strong { color: var(--muted); font-size: 12px; }
.turn p { margin: 0; }
.hidden { display: none !important; }
footer { min-height: 80px; display: flex; align-items: center; gap: 22px; color: var(--muted); font-size: 13px; }

@media (max-width: 700px) {
  main { width: min(100% - 28px, 880px); }
  .intro { padding-top: 32px; }
  h1 { font-size: 27px; }
  .architecture { grid-template-columns: 1fr; }
  .architecture-arrow { transform: rotate(90deg); justify-self: center; }
  .field-grid, .unlock-form { grid-template-columns: 1fr; }
  .walkthrough li { grid-template-columns: 72px 1fr; gap: 10px; }
  footer { align-items: flex-start; flex-direction: column; justify-content: center; gap: 4px; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; }
}