/* 智岛OS — dark gray + green.
   Design language: Linear (near-black canvas, surface ladder, 1px hairlines, one accent, no shadows),
   Vercel (display weight ≤ 600, tight tracking, mono eyebrows). The product is shown through UI windows,
   never through drawings of hardware. */
:root {
  color-scheme: dark;
  --canvas: #0b0c0d;
  --s1: #121315;
  --s2: #17191b;
  --s3: #1e2023;
  --line: #25282c;
  --line-2: #34373c;
  --ink: #f3f4f5;
  --ink-2: #c8cdd3;
  --ink-3: #8b9097;
  --ink-4: #62666d;
  --accent: #34d8c0;
  --accent-ink: #03211d;
  --radius: 12px;
  --max: 1200px;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--canvas); color: var(--ink);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
img, svg { max-width: 100%; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
[id] { scroll-margin-top: 72px; }
:focus-visible { outline: 2px solid color-mix(in srgb, var(--accent) 60%, transparent); outline-offset: 2px; border-radius: 6px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

/* header */
.top { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--canvas) 82%, transparent); backdrop-filter: saturate(140%) blur(12px); -webkit-backdrop-filter: saturate(140%) blur(12px); border-bottom: 1px solid var(--line); }
.top .wrap { display: flex; align-items: center; gap: 28px; height: 56px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 16px; text-decoration: none; white-space: nowrap; }
.brand img { width: 30px; height: 20px; display: block; }
.nav { display: flex; gap: 24px; margin-left: auto; font-size: 14px; }
.nav a { text-decoration: none; color: var(--ink-3); transition: color .15s; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); }
.top .btn { padding: 6px 14px; font-size: 13px; min-height: 34px; }
.menu-toggle { display: none; margin-left: auto; background: var(--s1); border: 1px solid var(--line); border-radius: 8px; padding: 6px 12px; color: var(--ink); font: inherit; font-size: 14px; min-height: 36px; }

/* buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 40px; padding: 9px 20px; border-radius: 999px; text-decoration: none; white-space: nowrap; font-weight: 500; font-size: 15px; border: 1px solid var(--accent); background: var(--accent); color: var(--accent-ink); transition: filter .15s; }
.btn:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--line-2); }
.btn.ghost:hover { border-color: var(--ink-3); filter: none; }

/* type */
section { padding: 112px 0; }
section.soft { background: var(--s1); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.eyebrow { font-family: var(--mono); color: var(--accent); font-size: 12px; letter-spacing: .08em; margin: 0 0 14px; }
h1, h2, h3 { margin: 0; font-weight: 600; }
h1 { font-size: clamp(36px, 6.2vw, 68px); line-height: 1.12; letter-spacing: -.02em; }
h2 { font-size: clamp(28px, 4vw, 42px); line-height: 1.2; letter-spacing: -.015em; margin-bottom: 14px; }
h3 { font-size: 18px; line-height: 1.4; margin-bottom: 8px; font-weight: 500; }
.lead { font-size: clamp(16px, 2vw, 19px); color: var(--ink-2); max-width: 640px; margin: 22px 0 32px; }
.sub { color: var(--ink-3); max-width: 660px; margin: 0 0 44px; font-size: 17px; }
.muted { color: var(--ink-4); font-size: 14px; }

/* hero */
.hero { padding: 96px 0 0; text-align: center; position: relative; overflow: hidden; }
.hero .lead { margin-left: auto; margin-right: auto; }
.hero .actions { display: flex; gap: 12px; flex-wrap: wrap; justify-content: center; }
.hero-shot { position: relative; max-width: 880px; margin: 64px auto 0; text-align: left; }
.hero-shot::before { content: ""; position: absolute; inset: -10% 8% 20%; z-index: -1; background: radial-gradient(closest-side, color-mix(in srgb, var(--accent) 16%, transparent), transparent); filter: blur(40px); }
.facts { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); margin-top: 72px; text-align: left; }
.facts div { padding: 26px 24px 30px; border-left: 1px solid var(--line); }
.facts div:first-child { border-left: 0; padding-left: 0; }
.facts b { display: block; font-size: 22px; font-weight: 600; letter-spacing: -.01em; }
.facts span { color: var(--ink-3); font-size: 14px; }

/* product windows */
.mock { background: linear-gradient(180deg, #15171a, #0f1012); border: 1px solid var(--line-2); border-radius: 16px; box-shadow: 0 40px 80px -30px rgba(0,0,0,.9), inset 0 1px 0 rgba(255,255,255,.05); overflow: hidden; font-size: 15px; }
.mock .bar { display: flex; align-items: center; gap: 7px; padding: 12px 16px; border-bottom: 1px solid var(--line); }
.mock .bar i { width: 10px; height: 10px; border-radius: 50%; background: #2c2f33; }
.mock .bar span { margin-left: 10px; font-size: 12px; color: var(--ink-4); font-family: var(--mono); }
.mock .body { padding: 24px 26px 28px; }
.mock .split-body { display: grid; grid-template-columns: 1.4fr 1fr; }
.mock .split-body > div { padding: 24px 26px 28px; }
.mock .split-body > div + div { border-left: 1px solid var(--line); background: rgba(255,255,255,.015); }
.q { margin-left: auto; max-width: 82%; width: fit-content; background: var(--s3); border: 1px solid var(--line-2); border-radius: 16px 16px 4px 16px; padding: 10px 15px; }
.a { margin-top: 16px; color: var(--ink-2); }
.a p { margin: 0 0 12px; }
.a b { color: var(--ink); font-weight: 600; }
.cite { display: inline-flex; align-items: center; gap: 8px; font-size: 12px; color: var(--ink-3); border: 1px solid var(--line-2); border-radius: 8px; padding: 4px 10px; margin: 0 6px 6px 0; background: var(--s2); }
.cite::before { content: ""; width: 9px; height: 11px; border-radius: 2px; border: 1px solid var(--ink-4); }
.mock h4 { margin: 0 0 12px; font-size: 12px; font-weight: 500; color: var(--ink-4); font-family: var(--mono); letter-spacing: .04em; }
.list { list-style: none; margin: 0; padding: 0; }
.list li { display: flex; justify-content: space-between; gap: 12px; align-items: baseline; padding: 10px 0; border-bottom: 1px solid var(--line); font-size: 14px; color: var(--ink-2); }
.list li:last-child { border-bottom: 0; }
.list small { display: block; color: var(--ink-4); font-size: 12px; }
.due { font-size: 12px; white-space: nowrap; color: var(--ink-3); font-family: var(--mono); }
.due.late { color: #ff8a80; }
.due.soon { color: var(--accent); }
.list b { font-family: var(--mono); color: var(--ink); font-weight: 500; }

/* grids and cards */
.grid { display: grid; gap: 16px; }
.g2 { grid-template-columns: repeat(2, 1fr); }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g4 { grid-template-columns: repeat(4, 1fr); }
.card { background: var(--s1); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; }
section.soft .card { background: var(--s2); }
.card p { margin: 0; color: var(--ink-3); font-size: 15px; }
.card .tag { display: inline-block; font-family: var(--mono); font-size: 11px; letter-spacing: .06em; color: var(--ink-2); background: var(--s3); border: 1px solid var(--line-2); border-radius: 999px; padding: 1px 9px; margin-bottom: 14px; }
.card ul { margin: 14px 0 0; padding-left: 18px; color: var(--ink-3); font-size: 15px; }
.card ul li { margin: 4px 0; }
a.card { text-decoration: none; display: block; transition: border-color .15s, background .15s; }
a.card:hover { border-color: var(--line-2); background: var(--s2); }

/* tables */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--s1); }
table { border-collapse: collapse; width: 100%; font-size: 15px; min-width: 560px; }
th, td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--line); vertical-align: top; }
td { color: var(--ink-2); }
thead th { font-family: var(--mono); font-weight: 400; font-size: 12px; letter-spacing: .06em; color: var(--ink-3); }
tbody th { font-weight: 500; white-space: nowrap; }
tbody tr:last-child td, tbody tr:last-child th { border-bottom: 0; }
td.yes { color: var(--accent); }
td a { color: var(--accent); text-decoration: none; }

/* chips */
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chips span { border: 1px solid var(--line-2); border-radius: 999px; padding: 4px 13px; font-size: 14px; color: var(--ink-2); background: var(--s2); }

/* steps */
.steps { counter-reset: s; }
.steps .card { position: relative; padding-top: 60px; }
.steps .card::before { counter-increment: s; content: "0" counter(s); position: absolute; top: 24px; left: 26px; font-family: var(--mono); font-size: 13px; color: var(--accent); }

/* flow */
.flow { display: grid; grid-template-columns: 1fr auto 1.1fr auto 1fr; gap: 16px; align-items: center; }
.flow .col { display: grid; gap: 10px; }
.flow .node { border: 1px solid var(--line); border-radius: 10px; padding: 12px 16px; background: var(--s1); font-size: 15px; }
.flow .node small { display: block; color: var(--ink-4); font-size: 13px; }
.flow .box { border: 1px solid var(--line-2); border-radius: 14px; padding: 22px; background: #101113; position: relative; }
.flow .box::after { content: ""; position: absolute; left: 22px; bottom: 14px; width: 36px; height: 2px; border-radius: 2px; background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.flow .box b { display: block; font-size: 17px; font-weight: 600; margin-bottom: 10px; }
.flow .box ul { margin: 0 0 12px; padding-left: 18px; color: var(--ink-3); font-size: 14px; }
.flow .arrow { color: var(--ink-4); font-size: 20px; text-align: center; }

/* faq */
.faq { max-width: 860px; }
details { border-bottom: 1px solid var(--line); padding: 20px 0; }
details summary { cursor: pointer; font-weight: 500; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; color: var(--ink-4); font-family: var(--mono); }
details[open] summary::after { content: "−"; }
details p { margin: 12px 0 0; color: var(--ink-3); }
details a { color: var(--ink-2); }

/* contact */
.contact { display: grid; grid-template-columns: 1.1fr 1fr; gap: 48px; align-items: start; }
.contact-list { display: grid; gap: 10px; }
.contact-list a { display: flex; justify-content: space-between; align-items: center; gap: 16px; text-decoration: none; border: 1px solid var(--line); background: var(--s2); border-radius: 12px; padding: 16px 20px; }
.contact-list a[href]:hover { border-color: var(--line-2); }
.contact-list span { color: var(--ink-4); font-size: 13px; }
.contact-list b { font-weight: 500; font-size: 16px; }

/* footer */
footer { border-top: 1px solid var(--line); padding: 40px 0 56px; color: var(--ink-4); font-size: 13px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 12px 28px; justify-content: space-between; }
footer a { text-decoration: none; }
footer a:hover { color: var(--ink-2); }

/* inner page header */
.page-head { padding: 88px 0 56px; border-bottom: 1px solid var(--line); }
.page-head .lead { margin-bottom: 0; }
.toc { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 32px; }
.toc a { text-decoration: none; font-size: 14px; border: 1px solid var(--line-2); border-radius: 999px; padding: 5px 14px; color: var(--ink-3); }
.toc a:hover { color: var(--ink); border-color: var(--ink-4); }

@media (max-width: 960px) {
  .g4 { grid-template-columns: repeat(2, 1fr); }
  .g3 { grid-template-columns: 1fr 1fr; }
  .flow { grid-template-columns: 1fr; }
  .flow .arrow { transform: rotate(90deg); }
  .contact { grid-template-columns: 1fr; }
  .facts { grid-template-columns: repeat(2, 1fr); }
  .facts div:nth-child(3) { border-left: 0; padding-left: 0; }
  .facts div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .mock .split-body { grid-template-columns: 1fr; }
  .mock .split-body > div + div { border-left: 0; border-top: 1px solid var(--line); }
}
@media (max-width: 720px) {
  .wrap { padding: 0 16px; }
  section { padding: 72px 0; }
  .hero { padding-top: 64px; }
  .g2, .g3, .g4 { grid-template-columns: 1fr; }
  .menu-toggle { display: block; }
  .top .btn { display: none; }
  .nav { display: none; position: absolute; top: 56px; left: 0; right: 0; flex-direction: column; gap: 0; background: var(--canvas); border-bottom: 1px solid var(--line); padding: 8px 16px 14px; }
  .nav a { padding: 11px 0; font-size: 16px; }
  .top.open .nav { display: flex; }
  .facts div { padding: 20px 12px 22px; }
  .facts div:nth-child(odd) { padding-left: 0; }
  .facts b { font-size: 19px; }
  .mock .body, .mock .split-body > div { padding: 18px 16px 20px; }
  .q { max-width: 100%; }
}

/* architecture diagram */
.arch { display: grid; grid-template-columns: 1fr 2.6fr 1fr; gap: 0; align-items: stretch; margin-top: 8px; }
.arch-col { display: flex; flex-direction: column; justify-content: center; gap: 10px; position: relative; }
.arch-col h5, .arch-core h5 { margin: 0 0 4px; font-family: var(--mono); font-size: 11px; letter-spacing: .08em; color: var(--ink-4); font-weight: 400; }
.arch-item { border: 1px solid var(--line); background: var(--s1); border-radius: 10px; padding: 11px 14px; font-size: 14px; position: relative; }
.arch-item small { display: block; color: var(--ink-4); font-size: 12px; }
.arch-item.opt { border-style: dashed; }
.arch-link { position: relative; width: 56px; flex: none; }
.arch-in, .arch-out { display: grid; grid-template-columns: 1fr 56px; }
.arch-out { grid-template-columns: 56px 1fr; }
.wire { position: relative; }
.wire::before { content: ""; position: absolute; top: 50%; left: 6px; right: 6px; height: 1px; background: linear-gradient(90deg, transparent, var(--accent), transparent); box-shadow: 0 0 8px var(--accent); opacity: .7; }
.wire::after { content: ""; position: absolute; top: calc(50% - 4px); right: 6px; border: 4px solid transparent; border-left: 6px solid var(--accent); border-right: 0; }
.wire.both::after { display: none; }
.wire .lbl { position: absolute; left: 50%; top: calc(50% + 8px); transform: translateX(-50%); font-size: 10px; color: var(--ink-4); white-space: nowrap; font-family: var(--mono); }
.arch-core { border: 1px solid color-mix(in srgb, var(--accent) 45%, var(--line-2)); border-radius: 18px; padding: 18px; background: linear-gradient(180deg, #111315, #0d0e10); box-shadow: 0 0 0 1px rgba(52,216,192,.06), 0 30px 80px -40px rgba(52,216,192,.35); position: relative; }
.arch-core > .head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 12px; }
.arch-core > .head b { font-size: 16px; font-weight: 600; }
.arch-core > .head span { font-family: var(--mono); font-size: 11px; color: var(--accent); letter-spacing: .06em; }
.layer { border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; background: rgba(255,255,255,.015); }
.layer + .layer { margin-top: 8px; }
.layer h6 { margin: 0 0 8px; font-size: 11px; font-weight: 400; color: var(--ink-4); font-family: var(--mono); letter-spacing: .06em; }
.layer .cells { display: grid; grid-template-columns: repeat(var(--n, 3), 1fr); gap: 6px; }
.layer .cells span { border: 1px solid var(--line-2); background: var(--s2); border-radius: 8px; padding: 7px 10px; font-size: 13px; color: var(--ink-2); text-align: center; }
.layer.accent { border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); }
.layer.accent .cells span { border-color: color-mix(in srgb, var(--accent) 30%, var(--line-2)); }
.arch-note { margin-top: 14px; display: flex; flex-wrap: wrap; gap: 8px 22px; font-size: 13px; color: var(--ink-3); }
.arch-note i { display: inline-block; width: 18px; height: 1px; vertical-align: middle; margin-right: 6px; background: var(--accent); box-shadow: 0 0 6px var(--accent); }
.arch-note i.dash { background: none; border-top: 1px dashed var(--ink-3); box-shadow: none; }
@media (max-width: 960px) {
  .arch { grid-template-columns: 1fr; gap: 14px; }
  .arch-in, .arch-out { grid-template-columns: 1fr; }
  .wire { height: 34px; }
  .wire::before { top: 4px; bottom: 4px; left: 50%; right: auto; width: 1px; height: auto; background: linear-gradient(180deg, transparent, var(--accent), transparent); }
  .wire::after { top: auto; bottom: 4px; right: auto; left: calc(50% - 4px); border: 4px solid transparent; border-top: 6px solid var(--accent); border-bottom: 0; }
  .wire .lbl { top: 50%; left: calc(50% + 10px); transform: translateY(-50%); }
  .arch-out { order: 3; }
  .layer .cells { grid-template-columns: repeat(2, 1fr); }
}

/* product photos */
.hero-photo { margin: 56px auto 0; max-width: 1120px; border-radius: 22px; overflow: hidden; border: 1px solid var(--line); box-shadow: 0 40px 100px -40px rgba(0,0,0,.9); }
.hero-photo img { display: block; width: 100%; height: auto; }
.shot { max-width: 880px; margin: 48px auto 0; }
.photo-card { padding: 0 0 24px; overflow: hidden; }
.photo-card img { display: block; width: 100%; height: auto; aspect-ratio: 16 / 9; object-fit: cover; margin-bottom: 20px; border-bottom: 1px solid var(--line); }
.photo-card > :not(img) { margin-left: 26px; margin-right: 26px; }
.photo-card ul { padding-left: 18px; }
@media (max-width: 720px) { .hero-photo { margin-top: 40px; border-radius: 14px; } }

/* ---------- v12: Apple-style sections ---------- */
/* 1. hero: one-line lead, wide photo */
.hero .lead.one { max-width: none; margin-bottom: 28px; }
.hero-photo.wide { max-width: 1320px; margin: 56px auto 0; border-radius: 26px; }

/* 2. highlight cards with UI */
.hl-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.hl { background: var(--s2); border: 1px solid var(--line); border-radius: 22px; padding: 34px 34px 0; overflow: hidden; display: flex; flex-direction: column; }
.hl h3 { font-size: 24px; font-weight: 600; letter-spacing: -.01em; margin-bottom: 10px; }
.hl p { color: var(--ink-3); margin: 0 0 26px; max-width: 520px; }
.hl .mock { margin-top: auto; border-radius: 14px 14px 0 0; border-bottom: 0; box-shadow: none; }
.hl.wide { grid-column: 1 / -1; display: grid; grid-template-columns: 1fr 1.25fr; gap: 40px; padding: 40px 0 0 40px; }
.hl.wide .text { padding-bottom: 40px; align-self: center; }
.hl.wide .mock { border-radius: 14px 0 0 0; border-right: 0; }

/* 3. big numbers */
.numbers { display: grid; grid-template-columns: repeat(5, 1fr); gap: 0; }
.numbers div { padding: 36px 24px 34px; border-left: 1px solid var(--line); }
.numbers div:first-child { border-left: 0; }
.numbers b { display: block; font-size: clamp(34px, 4.4vw, 52px); font-weight: 600; letter-spacing: -.03em; line-height: 1.1; }
.numbers b small { font-size: .45em; font-weight: 500; letter-spacing: 0; margin-left: 4px; color: var(--ink-2); }
.numbers span { color: var(--ink-3); font-size: 14px; }
sup.fn { font-size: 11px; color: var(--ink-4); margin-left: 2px; }

/* 4. roles tabs */
.tabs { display: inline-flex; gap: 4px; padding: 4px; border: 1px solid var(--line); border-radius: 999px; background: var(--s1); margin-bottom: 36px; flex-wrap: wrap; }
.tabs button { font: inherit; font-size: 15px; color: var(--ink-3); background: none; border: 0; border-radius: 999px; padding: 8px 18px; cursor: pointer; min-height: 40px; }
.tabs button[aria-selected="true"] { background: var(--s3); color: var(--ink); box-shadow: inset 0 0 0 1px var(--line-2); }
.panel { display: grid; grid-template-columns: 1fr 1.15fr; gap: 48px; align-items: center; }
.panel[hidden] { display: none; }
.panel h3 { font-size: 26px; font-weight: 600; margin-bottom: 14px; letter-spacing: -.01em; }
.panel p { color: var(--ink-3); }
.panel ul { margin: 18px 0 0; padding-left: 18px; color: var(--ink-2); }
.panel li { margin: 6px 0; }

/* 7. model chooser */
.chooser { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.pick-col { text-align: center; }
.pick-col img { display: block; width: 100%; height: auto; aspect-ratio: 16 / 10; object-fit: cover; border-radius: 16px; border: 1px solid var(--line); margin-bottom: 22px; }
.pick-col h3 { font-size: 26px; font-weight: 600; margin-bottom: 6px; }
.pick-col .for { color: var(--ink-3); font-size: 15px; margin-bottom: 18px; }
.pick-col dl { margin: 0; border-top: 1px solid var(--line); }
.pick-col dt { font-size: 12px; color: var(--ink-4); padding-top: 14px; font-family: var(--mono); letter-spacing: .04em; }
.pick-col dd { margin: 4px 0 0; padding-bottom: 14px; border-bottom: 1px solid var(--line); color: var(--ink-2); font-size: 15px; }
.pick-col .more-link { display: inline-block; margin-top: 18px; color: var(--accent); text-decoration: none; }
.pick-col .more-link::after { content: " ›"; }
.soft-row { margin-top: 28px; border: 1px solid var(--line); border-radius: 14px; padding: 18px 22px; display: flex; gap: 12px 20px; align-items: baseline; flex-wrap: wrap; background: var(--s1); }
.soft-row b { font-weight: 600; }
.soft-row span { color: var(--ink-3); font-size: 15px; }
.soft-row a { margin-left: auto; color: var(--accent); text-decoration: none; font-size: 15px; }

/* 10. footnotes */
.footnotes { border-top: 1px solid var(--line); padding-top: 28px; padding-bottom: 8px; color: var(--ink-4); font-size: 12px; }
.footnotes ol { margin: 0; padding-left: 18px; }
.footnotes li { margin: 4px 0; }

/* 11. reveal on scroll (only when JS runs and motion is allowed) */
@media (prefers-reduced-motion: no-preference) {
  html.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .7s ease, transform .7s ease; }
  html.js .reveal.in { opacity: 1; transform: none; }
}

@media (max-width: 960px) {
  .hl-grid { grid-template-columns: 1fr; }
  .hl.wide { grid-template-columns: 1fr; padding: 34px 34px 0; gap: 0; }
  .hl.wide .text { padding-bottom: 26px; }
  .hl.wide .mock { border-radius: 14px 14px 0 0; border-right: 1px solid var(--line-2); }
  .numbers { grid-template-columns: repeat(2, 1fr); }
  .numbers div:nth-child(odd) { border-left: 0; }
  .numbers div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .panel { grid-template-columns: 1fr; gap: 28px; }
  .chooser { grid-template-columns: 1fr; gap: 40px; }
}
@media (max-width: 720px) {
  .hl { padding: 26px 20px 0; border-radius: 18px; }
  .hl.wide { padding: 26px 20px 0; }
  .numbers div { padding: 24px 12px; }
  .numbers div:nth-child(odd) { padding-left: 0; }
  .hero-photo.wide { border-radius: 16px; margin-top: 40px; }
}

/* cut-out devices on a lit stage */
.hero-stage { position: relative; max-width: 760px; margin: 72px auto 0; padding: 10px 0 56px; }
.hero-stage::before { content: ""; position: absolute; inset: -18% 4% 8%; background: radial-gradient(closest-side, rgba(255,255,255,.075), rgba(52,216,192,.03) 55%, transparent 75%); }
.hero-stage::after { content: ""; position: absolute; left: 12%; right: 12%; bottom: 34px; height: 44px; background: radial-gradient(closest-side, rgba(0,0,0,.95), transparent); filter: blur(6px); }
.hero-stage img { position: relative; z-index: 1; display: block; width: 100%; height: auto; }
.stage { position: relative; aspect-ratio: 16 / 10; display: grid; place-items: center; border-radius: 16px; border: 1px solid var(--line); background: radial-gradient(ellipse at 50% 38%, #202327, #121315 72%); margin-bottom: 22px; overflow: hidden; }
.stage::after { content: ""; position: absolute; left: 16%; right: 16%; bottom: 14%; height: 18px; background: radial-gradient(closest-side, rgba(0,0,0,.9), transparent); filter: blur(4px); }
.stage img { position: relative; z-index: 1; width: 78%; height: auto; }
.stage.tall img { width: 52%; height: auto; }
.photo-card .stage { border-radius: 0; border: 0; border-bottom: 1px solid var(--line); margin: 0 0 20px; }
.photo-card .stage img { width: 78%; height: auto; aspect-ratio: auto; border: 0; margin: 0; }
.photo-card .stage.tall img { width: 52%; height: auto; }
.pick-col .stage img { width: 78%; height: auto; aspect-ratio: auto; object-fit: contain; border: 0; border-radius: 0; margin: 0; }
.pick-col .stage.tall img { width: 52%; height: auto; }

/* smaller device art until real renders arrive */
.stage { aspect-ratio: 16 / 9; }
.pick-col .stage img, .photo-card .stage img { width: 58%; }
.pick-col .stage.tall img, .photo-card .stage.tall img { width: 36%; }

/* window controls: red / yellow / green */
.mock .bar i:nth-child(1) { background: #ff5f57; }
.mock .bar i:nth-child(2) { background: #febc2e; }
.mock .bar i:nth-child(3) { background: #28c840; }

/* WeChat QR in the contact list */
.qr-row { display: flex; justify-content: space-between; align-items: center; gap: 16px; border: 1px solid var(--line); background: var(--s2); border-radius: 12px; padding: 16px 20px; }
.qr-row > span { color: var(--ink-4); font-size: 13px; }
.qr { margin: 0; text-align: center; }
.qr img { display: block; width: 132px; height: 132px; padding: 8px; background: #fff; border-radius: 10px; }
.qr figcaption { margin-top: 8px; font-size: 12px; color: var(--ink-3); }