:root {
  --ink: #191c19;
  --muted: #62665f;
  --paper: #f4f1e8;
  --surface: #fbfaf6;
  --line: #d9d6cc;
  --accent: #176b4d;
  --accent-dark: #10523a;
  --accent-soft: #dcebe3;
  --radius: 12px;
  --max: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
.site-header, footer {
  width: min(calc(100% - 48px), var(--max));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-header { height: 80px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; text-decoration: none; letter-spacing: -.02em; }
.brand-mark { display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; background: var(--ink); color: var(--paper); }
.header-link, footer a { color: var(--muted); font-size: 14px; text-underline-offset: 4px; }
.header-link:hover, footer a:hover { color: var(--accent); }
main { overflow: hidden; }
.hero, .details-section, .content-section, .faq-section { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; }
.hero { padding: 104px 0 112px; text-align: center; }
.eyebrow { margin: 0 0 18px; color: var(--accent); font-size: 12px; line-height: 1.2; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; }
h1, h2 { margin: 0; font-weight: 650; letter-spacing: -.045em; line-height: 1.04; }
h1 { color: var(--muted); font-size: clamp(32px, 5vw, 60px); }
h2 { font-size: clamp(32px, 4vw, 48px); }
.answer-wrap { margin: 20px auto 34px; }
.os-answer { margin: 0; color: var(--ink); font-size: clamp(50px, 9vw, 104px); font-weight: 760; letter-spacing: -.065em; line-height: .98; text-wrap: balance; }
.confidence { margin: 20px 0 0; color: var(--muted); font-size: 14px; }
.copy-button { min-height: 48px; display: inline-flex; align-items: center; gap: 9px; padding: 0 20px; border: 0; border-radius: 8px; background: var(--accent); color: white; font: inherit; font-weight: 650; cursor: pointer; transition: background .18s ease, transform .18s ease; }
.copy-button:hover { background: var(--accent-dark); }
.copy-button:active { transform: translateY(1px); }
.copy-button svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.8; }
.privacy-note { margin: 18px 0 0; color: var(--muted); font-size: 13px; }
button:focus-visible, a:focus-visible, summary:focus-visible { outline: 3px solid color-mix(in srgb, var(--accent) 35%, transparent); outline-offset: 3px; }
.details-section { padding: 80px 0 96px; border-top: 1px solid var(--line); }
.section-heading { display: flex; justify-content: space-between; align-items: end; margin-bottom: 44px; }
.detail-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 0; }
.detail-card { min-height: 142px; padding: 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.detail-card dt { color: var(--muted); font-size: 13px; }
.detail-card dd { margin: 22px 0 0; font-size: 21px; font-weight: 650; letter-spacing: -.025em; overflow-wrap: anywhere; }
.detail-card p { margin: 5px 0 0; color: var(--muted); font-size: 12px; }
.ip-card { background: var(--accent-soft); border-color: color-mix(in srgb, var(--accent) 25%, var(--line)); }
.technical-details { margin-top: 14px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.technical-details summary { padding: 18px 22px; cursor: pointer; font-weight: 600; }
.technical-body { padding: 0 22px 20px; display: grid; gap: 14px; }
.technical-body div { display: grid; grid-template-columns: 120px 1fr; gap: 16px; }
.technical-body span { color: var(--muted); font-size: 13px; }
.technical-body code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 12px; overflow-wrap: anywhere; }
.content-section { padding: 96px 0; display: grid; grid-template-columns: 1fr 1fr; gap: 80px; border-top: 1px solid var(--line); }
.content-copy { color: var(--muted); font-size: 18px; }
.content-copy p:first-child { margin-top: 0; }
.faq-section { padding: 96px 0 112px; border-top: 1px solid var(--line); }
.faq-section h2 { margin-bottom: 44px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { padding: 22px 4px; cursor: pointer; font-size: 18px; font-weight: 650; list-style-position: outside; }
.faq-list p { max-width: 740px; margin: -4px 0 24px; color: var(--muted); }
footer { min-height: 120px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }
.toast { position: fixed; right: 24px; bottom: 24px; padding: 12px 16px; border-radius: 8px; background: var(--ink); color: white; font-size: 14px; box-shadow: 0 4px 18px rgba(0,0,0,.16); opacity: 0; pointer-events: none; transform: translateY(8px); transition: opacity .18s ease, transform .18s ease; }
.toast.visible { opacity: 1; transform: translateY(0); }

@media (max-width: 760px) {
  .site-header, footer, .hero, .details-section, .content-section, .faq-section { width: min(calc(100% - 32px), var(--max)); }
  .site-header { height: 68px; }
  .header-link { display: none; }
  .hero { padding: 72px 0 80px; }
  .detail-grid { grid-template-columns: 1fr; }
  .detail-card { min-height: 112px; }
  .detail-card dd { margin-top: 12px; }
  .content-section { grid-template-columns: 1fr; gap: 28px; padding: 72px 0; }
  .details-section, .faq-section { padding: 72px 0; }
  .technical-body div { grid-template-columns: 1fr; gap: 4px; }
  footer { align-items: flex-start; flex-direction: column; justify-content: center; gap: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}