/* QyanHub 千衍 AI — qyanhub.ai
   Layout: dark "abyss" canvas, 1200px measure, hero = thesis + live code; sections divided by hairlines,
   eyebrows use the brand's 2:3:4 token dots. Single deliberate dark theme (brand book p.17). */
@font-face { font-family: "Manrope"; src: url("../fonts/Manrope-var.woff2") format("woff2"); font-weight: 200 800; font-display: swap; }
@font-face { font-family: "JetBrains Mono"; src: url("../fonts/JetBrainsMono-var.woff2") format("woff2"); font-weight: 100 800; font-display: swap; }

:root {
  color-scheme: dark;
  /* colour */
  --abyss: #0B1220;        /* 深海墨 page ground */
  --abyss-2: #0E1628;      /* alternate band */
  --surface: #121C31;      /* cards */
  --surface-2: #17233D;    /* raised / hover */
  --line: rgba(150, 172, 214, 0.14);
  --line-2: rgba(150, 172, 214, 0.24);
  --text: #EAF0FA;
  --text-2: #AEBBD3;
  --text-3: #7E8DAA;
  --blue: #4C6BFF;         /* 千衍蓝 · dark-mode value */
  --blue-hi: #6481FF;
  --azure: #22C3FF;        /* 天际蓝 */
  --cyan: #2EF2D8;         /* 云海青 */
  --dawn: #F98942;         /* 曦光橙 ≤5% */
  --ok: #2EE6A6;
  --code-bg: #0A1122;
  /* type */
  --font-sans: "Manrope", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Noto Sans CJK SC", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --fs-hero: clamp(2.5rem, 5.4vw, 4.35rem);
  --fs-h1: clamp(2rem, 4.2vw, 3.2rem);
  --fs-h2: clamp(1.6rem, 3vw, 2.3rem);
  --fs-h3: 1.2rem;
  --fs-body: 1rem;
  --fs-small: 0.875rem;
  /* layout */
  --measure: 1200px;
  --gutter: clamp(16px, 4vw, 40px);
  --radius: 14px;
  --radius-lg: 20px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0; background: var(--abyss); color: var(--text);
  font-family: var(--font-sans); font-size: var(--fs-body); line-height: 1.65;
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
}
img, svg { max-width: 100%; }
a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible, summary:focus-visible {
  outline: 2px solid var(--azure); outline-offset: 3px; border-radius: 6px;
}
h1, h2, h3, h4 { margin: 0; font-weight: 750; letter-spacing: -0.015em; line-height: 1.15; text-wrap: balance; }
p { margin: 0; }
code, pre, kbd { font-family: var(--font-mono); }
::selection { background: rgba(76, 107, 255, 0.45); }

.wrap { width: 100%; max-width: calc(var(--measure) + 2 * var(--gutter)); margin-inline: auto; padding-inline: var(--gutter); }
.stack { display: flex; flex-direction: column; }
.muted { color: var(--text-2); }
.dim { color: var(--text-3); }
.mono { font-family: var(--font-mono); }
.num { font-variant-numeric: tabular-nums; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: env(safe-area-inset-top, 0px); z-index: 50;
  background: rgba(11, 18, 32, 0.78); backdrop-filter: saturate(1.4) blur(14px); -webkit-backdrop-filter: saturate(1.4) blur(14px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; gap: 28px; min-height: 68px; }
.brand { display: inline-flex; align-items: center; flex-shrink: 0; }
.brand img { height: 30px; width: auto; display: block; }
.nav { display: flex; align-items: center; gap: 4px; flex: 1; min-width: 0; }
.nav a { padding: 8px 12px; border-radius: 10px; color: var(--text-2); font-weight: 600; font-size: 0.95rem; white-space: nowrap; }
.nav a:hover { color: var(--text); background: rgba(255, 255, 255, 0.04); }
.nav a[aria-current="page"] { color: var(--text); }
.header-actions { display: flex; align-items: center; gap: 10px; margin-left: auto; }
.lang-toggle {
  display: inline-flex; border: 1px solid var(--line-2); border-radius: 999px; padding: 2px; font-size: 0.78rem; font-weight: 700;
}
.lang-toggle button { all: unset; cursor: pointer; padding: 4px 10px; border-radius: 999px; color: var(--text-3); }
.lang-toggle button[aria-pressed="true"] { background: var(--surface-2); color: var(--text); }
.menu-btn { all: unset; display: none; cursor: pointer; width: 40px; height: 40px; border-radius: 10px; align-items: center; justify-content: center; color: var(--text); }
.menu-btn svg { width: 22px; height: 22px; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 44px; padding: 0 20px; border-radius: 12px; font-weight: 700; font-size: 0.95rem; white-space: nowrap;
  border: 1px solid transparent; cursor: pointer; transition: background .18s, border-color .18s, transform .18s; font-family: inherit;
}
.btn-primary { background: var(--blue); color: #fff; box-shadow: 0 8px 24px -10px rgba(76, 107, 255, 0.8); }
.btn-primary:hover { background: var(--blue-hi); }
.btn-ghost { border-color: var(--line-2); color: var(--text); background: rgba(255, 255, 255, 0.02); }
.btn-ghost:hover { border-color: rgba(150, 172, 214, 0.45); background: rgba(255, 255, 255, 0.05); }
.btn-sm { min-height: 36px; padding: 0 14px; border-radius: 10px; font-size: 0.88rem; }
.btn-link { color: var(--text-2); font-weight: 600; padding: 8px 10px; }
.btn-link:hover { color: var(--text); }
.btn .arr { transition: transform .18s; }
.btn:hover .arr { transform: translateX(3px); }

/* ---------- token dots (brand 2:3:4) ---------- */
.dots { display: inline-flex; align-items: center; gap: 3px; flex-shrink: 0; }
.dots i { display: block; border-radius: 50%; background: var(--cyan); }
.dots i:nth-child(1) { width: 6px; height: 6px; }
.dots i:nth-child(2) { width: 9px; height: 9px; }
.dots i:nth-child(3) { width: 12px; height: 12px; }
.dots.blue i { background: var(--azure); }

.eyebrow { display: inline-flex; align-items: center; gap: 12px; font-size: 0.8rem; font-weight: 750; letter-spacing: 0.16em; text-transform: uppercase; color: var(--cyan); }
.pill {
  display: inline-flex; align-items: center; gap: 8px; padding: 6px 14px; border-radius: 999px;
  border: 1px solid rgba(46, 242, 216, 0.35); color: var(--cyan); font-size: 0.85rem; font-weight: 650; background: rgba(46, 242, 216, 0.05);
}

/* ---------- hero ---------- */
.hero { position: relative; overflow: hidden; border-bottom: 1px solid var(--line); }
.hero-bg { position: absolute; inset: 0; pointer-events: none; }
.hero-bg img { position: absolute; right: -8%; top: 4%; width: 92%; max-width: none; opacity: 0.55; }
.hero-bg::after { content: ""; position: absolute; inset: 0; background: radial-gradient(60% 70% at 20% 40%, rgba(11, 18, 32, 0.92) 0%, rgba(11, 18, 32, 0.55) 55%, rgba(11, 18, 32, 0.2) 100%); }
.hero .wrap { position: relative; display: grid; grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr); gap: 56px; align-items: center; padding-block: 88px 64px; }
.hero h1 { font-size: var(--fs-hero); font-weight: 800; letter-spacing: -0.035em; line-height: 1.02; margin-top: 26px; }
.hero .sub { margin-top: 22px; font-size: clamp(1.25rem, 2.2vw, 1.75rem); font-weight: 750; color: var(--text-2); letter-spacing: 0.01em; }
.hero .lede { margin-top: 14px; max-width: 34em; color: var(--text-2); }
.hero .cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.hero-strip { position: relative; border-top: 1px solid var(--line); }
.hero-strip .wrap { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; padding-block: 26px 30px; align-items: start; }
.hero-strip .item { display: flex; gap: 14px; align-items: flex-start; }
.hero-strip .item .dots { margin-top: 7px; }
.hero-strip .item > div > b { display: block; font-size: 1.02rem; }
.hero-strip .item > div > span { display: block; color: var(--text-3); font-size: 0.88rem; }

/* ---------- code window ---------- */
.code-win { background: linear-gradient(180deg, rgba(23, 35, 61, 0.92), rgba(14, 22, 40, 0.94)); border: 1px solid var(--line-2); border-radius: var(--radius-lg); box-shadow: 0 30px 80px -30px rgba(0, 0, 0, 0.7); min-width: 0; overflow: hidden; }
.code-head { display: flex; align-items: center; gap: 14px; padding: 12px 14px 0 18px; border-bottom: 1px solid var(--line); }
.code-head .lights { display: flex; gap: 6px; }
.code-head .lights i { width: 10px; height: 10px; border-radius: 50%; background: #2A3654; display: block; }
.tabs { display: flex; gap: 2px; overflow-x: auto; scrollbar-width: none; }
.tabs button { all: unset; cursor: pointer; padding: 8px 12px 10px; font-family: var(--font-mono); font-size: 0.8rem; color: var(--text-3); border-bottom: 2px solid transparent; white-space: nowrap; }
.tabs button[aria-selected="true"] { color: var(--text); border-bottom-color: var(--azure); }
.code-head .copy { margin-left: auto; margin-bottom: 8px; }
.copy { all: unset; cursor: pointer; font-size: 0.78rem; font-weight: 650; color: var(--text-3); padding: 4px 10px; border: 1px solid var(--line); border-radius: 8px; white-space: nowrap; }
.copy:hover { color: var(--text); border-color: var(--line-2); }
.copy.done { color: var(--ok); border-color: rgba(46, 230, 166, 0.4); }
pre.code { margin: 0; padding: 20px 22px 24px; overflow-x: auto; font-size: 0.86rem; line-height: 1.75; color: #D9E2F2; background: transparent; }
pre.code .k { color: #8FA8FF; } pre.code .s { color: var(--cyan); } pre.code .c { color: #64739A; } pre.code .f { color: var(--azure); } pre.code .n { color: #FFB27A; }
.panel[hidden] { display: none !important; }

/* ---------- sections ---------- */
.section { padding-block: 96px; border-bottom: 1px solid var(--line); }
.section.alt { background: var(--abyss-2); }
.section-head { display: flex; flex-direction: column; gap: 14px; max-width: 760px; margin-bottom: 48px; }
.section-head h2 { font-size: var(--fs-h2); }
.section-head p { color: var(--text-2); font-size: 1.05rem; }
.section-head.center { margin-inline: auto; text-align: center; align-items: center; }

.grid { display: grid; gap: 20px; }
.g2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.g3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.g4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; min-width: 0; }
.card h3 { font-size: var(--fs-h3); margin-bottom: 10px; }
.card p { color: var(--text-2); font-size: 0.95rem; }
.card .icon { width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center; background: rgba(76, 107, 255, 0.14); color: var(--azure); margin-bottom: 18px; }
.card .icon svg { width: 22px; height: 22px; }
.feature-list { list-style: none; margin: 16px 0 0; padding: 0; display: flex; flex-direction: column; gap: 9px; }
.feature-list li { display: flex; gap: 10px; color: var(--text-2); font-size: 0.93rem; }
.feature-list li::before { content: ""; flex-shrink: 0; width: 6px; height: 6px; border-radius: 50%; background: var(--cyan); margin-top: 0.62em; }

/* providers */
.providers { display: flex; flex-wrap: wrap; gap: 10px; }
.provider { display: inline-flex; align-items: center; gap: 10px; padding: 10px 16px; border-radius: 12px; border: 1px solid var(--line); background: rgba(255, 255, 255, 0.015); font-weight: 650; color: var(--text-2); }
.provider small { color: var(--text-3); font-weight: 500; }
.provider .tag { font-size: 0.7rem; padding: 2px 7px; border-radius: 6px; background: rgba(34, 195, 255, 0.12); color: var(--azure); font-weight: 700; }

/* two-way diagram */
.twoway { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); gap: 24px; align-items: center; }
.twoway .side { display: flex; flex-direction: column; gap: 10px; }
.twoway .side h3 { font-size: 1.05rem; color: var(--text-2); font-weight: 650; }
.twoway .hub { display: grid; place-items: center; width: 168px; height: 168px; border-radius: 50%; border: 1px solid var(--line-2); background: radial-gradient(circle, rgba(76, 107, 255, 0.18), rgba(11, 18, 32, 0) 70%); position: relative; }
.twoway .hub img { width: 84px; height: 84px; }
.twoway .hub::before, .twoway .hub::after { content: ""; position: absolute; top: 50%; width: 56px; height: 1px; background: linear-gradient(90deg, rgba(46, 242, 216, 0), var(--cyan)); }
.twoway .hub::before { right: 100%; } .twoway .hub::after { left: 100%; transform: scaleX(-1); }
.flow-note { margin-top: 28px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }

/* steps */
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; counter-reset: step; }
.step { position: relative; padding: 28px; border-radius: var(--radius-lg); border: 1px solid var(--line); background: var(--surface); min-width: 0; }
.step .n { font-family: var(--font-mono); font-size: 0.8rem; color: var(--cyan); font-weight: 700; letter-spacing: 0.08em; }
.step h3 { margin: 10px 0 8px; font-size: 1.15rem; }
.step p { color: var(--text-2); font-size: 0.93rem; }
.step code { display: inline-block; margin-top: 12px; font-size: 0.8rem; color: var(--azure); background: var(--code-bg); border: 1px solid var(--line); padding: 4px 9px; border-radius: 8px; overflow-wrap: anywhere; }

/* audience */
.aud .card { display: flex; flex-direction: column; }
.aud .who { font-size: 0.8rem; font-weight: 750; letter-spacing: 0.14em; text-transform: uppercase; color: var(--azure); margin-bottom: 8px; }
.aud .card .btn { margin-top: auto; align-self: flex-start; }
.aud .feature-list { margin-bottom: 24px; }

/* world */
.world { position: relative; overflow: hidden; }
.world-figure { margin-top: 8px; border-radius: var(--radius-lg); border: 1px solid var(--line); background: var(--abyss); overflow: hidden; }
.world-figure img { display: block; width: 100%; height: auto; opacity: 0.9; }
.world-caption { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; margin-top: 24px; }

/* faq */
.faq { display: flex; flex-direction: column; border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; gap: 20px; padding: 22px 0; font-weight: 700; font-size: 1.05rem; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--font-mono); color: var(--azure); font-size: 1.2rem; line-height: 1; transition: transform .2s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq .ans { padding: 0 0 22px; color: var(--text-2); max-width: 70ch; }

/* cta band */
.cta-band { padding-block: 88px; position: relative; overflow: hidden; }
.cta-band .box { position: relative; border-radius: 28px; border: 1px solid var(--line-2); padding: clamp(32px, 6vw, 64px); background: linear-gradient(120deg, rgba(76, 107, 255, 0.22), rgba(34, 195, 255, 0.08) 55%, rgba(46, 242, 216, 0.10)); display: flex; flex-wrap: wrap; gap: 28px; align-items: center; justify-content: space-between; overflow: hidden; }
.cta-band h2 { font-size: var(--fs-h2); max-width: 18em; }
.cta-band p { color: var(--text-2); margin-top: 10px; }
.cta-band .actions { display: flex; flex-wrap: wrap; gap: 12px; }

/* ---------- page hero (inner pages) ---------- */
.page-hero { border-bottom: 1px solid var(--line); position: relative; overflow: hidden; }
.page-hero .wrap { padding-block: 72px 56px; display: flex; flex-direction: column; gap: 16px; position: relative; }
.page-hero h1 { font-size: var(--fs-h1); max-width: 20em; }
.page-hero p { color: var(--text-2); font-size: 1.08rem; max-width: 46em; }
.page-hero .sea { position: absolute; right: -10%; bottom: -40%; width: 70%; opacity: 0.35; pointer-events: none; max-width: none; }

/* ---------- models ---------- */
.toolbar { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; padding: 16px; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); }
.search { flex: 1 1 260px; min-width: 0; display: flex; align-items: center; gap: 10px; padding: 0 14px; height: 44px; border-radius: 12px; border: 1px solid var(--line-2); background: var(--abyss); }
.search svg { width: 18px; height: 18px; color: var(--text-3); flex-shrink: 0; }
.search input { all: unset; flex: 1; min-width: 0; color: var(--text); font-size: 0.95rem; }
.search input::placeholder { color: var(--text-3); }
.seg { display: inline-flex; border: 1px solid var(--line-2); border-radius: 12px; padding: 3px; }
.seg button { all: unset; cursor: pointer; padding: 7px 12px; border-radius: 9px; font-size: 0.85rem; font-weight: 650; color: var(--text-3); white-space: nowrap; }
.seg button[aria-pressed="true"] { background: var(--surface-2); color: var(--text); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.chip { all: unset; cursor: pointer; padding: 7px 13px; border-radius: 999px; border: 1px solid var(--line); font-size: 0.85rem; font-weight: 650; color: var(--text-2); white-space: nowrap; }
.chip[aria-pressed="true"] { border-color: rgba(34, 195, 255, 0.55); color: var(--text); background: rgba(34, 195, 255, 0.10); }
.chip .ct { color: var(--text-3); font-weight: 500; margin-left: 4px; }
.data-note { display: flex; gap: 10px; align-items: center; margin-top: 16px; font-size: 0.85rem; color: var(--text-3); }
.data-note .badge { font-size: 0.72rem; font-weight: 750; padding: 3px 8px; border-radius: 6px; background: rgba(249, 137, 66, 0.14); color: var(--dawn); letter-spacing: 0.04em; }
.data-note .badge.live { background: rgba(46, 230, 166, 0.14); color: var(--ok); }
.model-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; margin-top: 20px; }
.model { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; display: flex; flex-direction: column; gap: 14px; min-width: 0; }
.model:hover { border-color: var(--line-2); }
.model-top { display: flex; gap: 12px; align-items: flex-start; }
.vlogo { width: 38px; height: 38px; border-radius: 10px; display: grid; place-items: center; font-weight: 800; font-size: 0.95rem; color: var(--text); background: var(--surface-2); border: 1px solid var(--line); flex-shrink: 0; }
.model-name { font-family: var(--font-mono); font-size: 0.9rem; font-weight: 650; overflow-wrap: anywhere; line-height: 1.4; }
.model-vendor { font-size: 0.8rem; color: var(--text-3); }
.model-top .copy { margin-left: auto; }
.prices { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; }
.price { background: var(--abyss); border: 1px solid var(--line); border-radius: 10px; padding: 8px 10px; }
.price span { display: block; font-size: 0.72rem; color: var(--text-3); }
.price b { font-family: var(--font-mono); font-size: 0.92rem; font-variant-numeric: tabular-nums; font-weight: 650; }
.model-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tag { font-size: 0.72rem; padding: 3px 8px; border-radius: 6px; border: 1px solid var(--line); color: var(--text-3); font-family: var(--font-mono); }
.empty { padding: 48px; text-align: center; color: var(--text-3); border: 1px dashed var(--line-2); border-radius: var(--radius-lg); margin-top: 20px; }

/* ---------- pricing ---------- */
.plans { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; align-items: stretch; }
.plan { display: flex; flex-direction: column; gap: 18px; padding: 32px; border-radius: var(--radius-lg); border: 1px solid var(--line); background: var(--surface); min-width: 0; }
.plan.featured { border-color: rgba(76, 107, 255, 0.6); background: linear-gradient(180deg, rgba(76, 107, 255, 0.14), var(--surface) 45%); }
.plan .who { font-size: 0.8rem; font-weight: 750; letter-spacing: 0.14em; text-transform: uppercase; color: var(--azure); }
.plan h3 { font-size: 1.5rem; }
.plan .price-line { font-size: 1.05rem; color: var(--text-2); }
.plan .price-line b { font-size: 2rem; color: var(--text); letter-spacing: -0.02em; font-weight: 800; }
.plan .feature-list { margin: 0; flex: 1; }
.plan .btn { align-self: stretch; }
.calc { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr); gap: 24px; }
.field { display: flex; flex-direction: column; gap: 8px; }
.field label { font-size: 0.85rem; font-weight: 700; color: var(--text-2); }
.field input, .field select, .field textarea { font: inherit; color: var(--text); background: var(--abyss); border: 1px solid var(--line-2); border-radius: 12px; padding: 11px 14px; width: 100%; min-width: 0; }
.field textarea { min-height: 120px; resize: vertical; }
.field .hint { font-size: 0.8rem; color: var(--text-3); }
.calc-out { display: flex; flex-direction: column; gap: 14px; padding: 28px; border-radius: var(--radius-lg); background: var(--abyss); border: 1px solid var(--line-2); }
.calc-out .row { display: flex; justify-content: space-between; gap: 16px; color: var(--text-2); font-size: 0.95rem; }
.calc-out .row b { font-family: var(--font-mono); color: var(--text); font-variant-numeric: tabular-nums; font-weight: 650; }
.calc-out .total { border-top: 1px solid var(--line); padding-top: 14px; font-size: 1.05rem; }
.calc-out .total b { font-size: 1.6rem; color: var(--cyan); }
table.t { width: 100%; border-collapse: collapse; font-size: 0.93rem; }
.t th, .t td { text-align: left; padding: 14px 16px; border-bottom: 1px solid var(--line); vertical-align: top; }
.t th { color: var(--text-3); font-weight: 700; font-size: 0.82rem; letter-spacing: 0.04em; }
.t td:first-child { font-weight: 700; color: var(--text); }
.t td { color: var(--text-2); }
.t .yes { color: var(--cyan); font-weight: 700; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); }

/* ---------- docs ---------- */
.docs { display: grid; grid-template-columns: 230px minmax(0, 1fr); gap: 48px; padding-block: 48px 96px; }
.docs-nav { position: sticky; top: calc(84px + env(safe-area-inset-top, 0px)); align-self: start; display: flex; flex-direction: column; gap: 2px; max-height: calc(100vh - 110px); overflow-y: auto; }
.docs-nav .grp { font-size: 0.75rem; font-weight: 750; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-3); margin: 18px 0 6px; }
.docs-nav .grp:first-child { margin-top: 0; }
.docs-nav a { padding: 7px 12px; border-radius: 9px; color: var(--text-2); font-size: 0.92rem; font-weight: 600; border-left: 2px solid transparent; }
.docs-nav a:hover { color: var(--text); background: rgba(255, 255, 255, 0.03); }
.docs-nav a.active { color: var(--text); border-left-color: var(--azure); background: rgba(34, 195, 255, 0.06); }
.doc { min-width: 0; display: flex; flex-direction: column; gap: 56px; }
.doc section { display: flex; flex-direction: column; gap: 16px; scroll-margin-top: 90px; }
.doc h2 { font-size: 1.6rem; }
.doc h3 { font-size: 1.1rem; margin-top: 8px; }
.doc p, .doc li { color: var(--text-2); max-width: 72ch; }
.doc ul { margin: 0; padding-left: 1.2em; display: flex; flex-direction: column; gap: 6px; }
.doc code.inline { font-size: 0.86em; background: var(--surface-2); border: 1px solid var(--line); padding: 1px 6px; border-radius: 6px; color: var(--text); overflow-wrap: anywhere; }
.doc .code-win { box-shadow: none; }
.callout { display: flex; gap: 14px; padding: 16px 18px; border-radius: var(--radius); border: 1px solid rgba(34, 195, 255, 0.3); background: rgba(34, 195, 255, 0.06); color: var(--text-2); font-size: 0.93rem; }
.callout.warn { border-color: rgba(249, 137, 66, 0.4); background: rgba(249, 137, 66, 0.07); }
.callout b { color: var(--text); }
.kv { display: grid; grid-template-columns: 180px minmax(0, 1fr); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.kv > div { padding: 12px 16px; border-bottom: 1px solid var(--line); font-size: 0.92rem; min-width: 0; overflow-wrap: anywhere; }
.kv > div:nth-child(odd) { background: var(--surface); font-weight: 700; color: var(--text); }
.kv > div:nth-child(even) { color: var(--text-2); font-family: var(--font-mono); font-size: 0.86rem; }
.kv > div:nth-last-child(-n+2) { border-bottom: 0; }

/* ---------- enterprise / about ---------- */
.process { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; border: 1px solid var(--line); border-radius: var(--radius-lg); overflow: hidden; }
.process > div { padding: 24px; border-right: 1px solid var(--line); min-width: 0; }
.process > div:last-child { border-right: 0; }
.process .n { font-family: var(--font-mono); color: var(--cyan); font-size: 0.8rem; font-weight: 700; }
.process h3 { font-size: 1.05rem; margin: 8px 0 6px; }
.process p { color: var(--text-2); font-size: 0.9rem; }
.contact { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: 32px; }
.contact form { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.contact form .full { grid-column: 1 / -1; }
.form-result { grid-column: 1 / -1; display: none; padding: 16px; border-radius: 12px; border: 1px solid rgba(46, 230, 166, 0.4); background: rgba(46, 230, 166, 0.06); color: var(--text-2); font-size: 0.92rem; white-space: pre-wrap; }
.form-result.show { display: block; }
.contact-list { display: flex; flex-direction: column; gap: 14px; }
.contact-item { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 16px 18px; border-radius: var(--radius); border: 1px solid var(--line); background: var(--surface); }
.contact-item span { color: var(--text-3); font-size: 0.85rem; display: block; }
.contact-item b { font-family: var(--font-mono); font-size: 0.95rem; overflow-wrap: anywhere; }
.story { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 56px; align-items: center; }
.quote { font-size: clamp(1.6rem, 3.2vw, 2.4rem); font-weight: 750; letter-spacing: 0.04em; line-height: 1.4; font-family: "Songti SC", "STSong", "Noto Serif SC", "Noto Serif CJK SC", serif; }
.quote-src { color: var(--text-3); margin-top: 10px; }
.mark-figure { display: grid; place-items: center; padding: 48px; border-radius: var(--radius-lg); border: 1px solid var(--line); background: radial-gradient(circle at 50% 45%, rgba(76, 107, 255, 0.16), rgba(11, 18, 32, 0) 65%), var(--surface); }
.mark-figure img { width: min(260px, 70%); height: auto; }
.facts { display: grid; grid-template-columns: 200px minmax(0, 1fr); border-top: 1px solid var(--line); }
.facts > div { padding: 16px 0; border-bottom: 1px solid var(--line); min-width: 0; }
.facts > div:nth-child(odd) { color: var(--text-3); font-weight: 650; font-size: 0.92rem; }

/* ---------- footer ---------- */
.site-footer { padding-block: 64px 40px; background: #080E1A; }
.site-footer .top { display: grid; grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr)); gap: 32px; }
.site-footer .logo img { height: 40px; width: auto; }
.site-footer .tagline { color: var(--text-2); margin-top: 16px; font-weight: 650; }
.site-footer .domains { color: var(--text-3); margin-top: 6px; font-size: 0.88rem; }
.site-footer h4 { font-size: 0.8rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-3); margin-bottom: 14px; }
.site-footer ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.site-footer ul a { color: var(--text-2); font-size: 0.93rem; }
.site-footer ul a:hover { color: var(--text); }
.site-footer .bottom { margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--line); display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; color: var(--text-3); font-size: 0.85rem; }

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  .hero .wrap { grid-template-columns: minmax(0, 1fr); gap: 40px; padding-block: 64px 48px; }
  .hero-strip .wrap, .g4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .plans, .g3, .steps { grid-template-columns: minmax(0, 1fr); }
  .site-footer .top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .process { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .process > div:nth-child(2) { border-right: 0; }
  .process > div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
}
@media (max-width: 900px) {
  .nav { display: none; position: absolute; left: 0; right: 0; top: 100%; z-index: 70; flex-direction: column; align-items: stretch; gap: 2px; padding: 12px var(--gutter) 20px; background: var(--abyss); border-bottom: 1px solid var(--line-2); box-shadow: 0 24px 48px -12px rgba(0, 0, 0, 0.6); max-height: calc(100vh - 80px); overflow-y: auto; }
  .nav.open { display: flex; }
  .nav a { padding: 13px 12px; border-bottom: 1px solid var(--line); border-radius: 0; }
  .nav a.nav-mobile-only:last-child { border-bottom: 0; color: var(--azure); }
  .menu-btn { display: inline-flex; align-items: center; justify-content: center; }
  .header-actions .btn-link { display: none; }
  .docs { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .docs-nav { position: static; max-height: none; flex-direction: row; flex-wrap: wrap; gap: 6px; }
  .docs-nav .grp { display: none; }
  .docs-nav a { border: 1px solid var(--line); border-radius: 999px; padding: 6px 12px; font-size: 0.85rem; }
  .calc, .contact, .story, .g2, .twoway, .flow-note, .world-caption { grid-template-columns: minmax(0, 1fr); }
  .twoway .hub { margin-inline: auto; }
  .twoway .hub::before, .twoway .hub::after { display: none; }
  .kv, .facts { grid-template-columns: minmax(0, 1fr); }
  .kv > div:nth-child(odd) { border-bottom: 0; padding-bottom: 4px; }
  .facts > div:nth-child(odd) { border-bottom: 0; padding-bottom: 0; }
  .section { padding-block: 72px; }
}
@media (max-width: 560px) {
  .hero-strip .wrap, .g4, .site-footer .top, .process { grid-template-columns: minmax(0, 1fr); }
  .process > div { border-right: 0; border-bottom: 1px solid var(--line); }
  .process > div:last-child { border-bottom: 0; }
  .contact form { grid-template-columns: minmax(0, 1fr); }
  .prices { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .hero-bg img { width: 160%; right: -40%; top: 30%; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

/* ---------- ticker (new models) ---------- */
.ticker { background: #080E1A; border-bottom: 1px solid var(--line); font-size: 0.82rem; color: var(--text-2); }
.ticker .wrap { display: flex; align-items: center; gap: 16px; min-height: 38px; }
.ticker .label { flex-shrink: 0; display: inline-flex; align-items: center; gap: 8px; font-weight: 750; color: var(--cyan); letter-spacing: 0.04em; }
.ticker .viewport { flex: 1; min-width: 0; overflow: hidden; mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); -webkit-mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); }
.ticker .track { display: inline-flex; gap: 28px; white-space: nowrap; animation: qtick 38s linear infinite; padding-left: 8px; }
.ticker .tk { display: inline-flex; align-items: center; gap: 8px; font-family: var(--font-mono); font-size: 0.8rem; }
.ticker .tk i { width: 5px; height: 5px; border-radius: 50%; background: var(--azure); display: block; }
.ticker a.more { flex-shrink: 0; color: var(--text-2); font-weight: 650; }
.ticker a.more:hover { color: var(--text); }
.ticker:hover .track { animation-play-state: paused; }
@keyframes qtick { from { transform: translateX(0); } to { transform: translateX(-50%); } }
.header-search { display: inline-flex; align-items: center; gap: 8px; height: 36px; padding: 0 10px 0 12px; border-radius: 10px; border: 1px solid var(--line-2); color: var(--text-3); font-size: 0.85rem; white-space: nowrap; }
.header-search svg { width: 16px; height: 16px; }
.header-search kbd { font-size: 0.7rem; border: 1px solid var(--line-2); border-radius: 5px; padding: 1px 5px; color: var(--text-3); }
.header-search:hover { color: var(--text); border-color: rgba(150, 172, 214, 0.45); }
.nav-mobile-only { display: none; }

/* ---------- feature visuals ---------- */
.feat-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.feat { display: flex; flex-direction: column; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); overflow: hidden; min-width: 0; }
.feat .vis { height: 168px; border-bottom: 1px solid var(--line); background: radial-gradient(120% 90% at 50% 0%, rgba(76, 107, 255, 0.10), rgba(11, 18, 32, 0) 70%), var(--abyss-2); display: grid; place-items: center; padding: 18px; }
.feat .vis svg { width: 100%; height: 100%; }
.feat .body { padding: 22px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.feat h3 { font-size: 1.08rem; }
.feat p { color: var(--text-2); font-size: 0.92rem; }
.feat .more { margin-top: auto; padding-top: 8px; font-size: 0.88rem; font-weight: 700; color: var(--azure); }
.mark-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 8px; width: 100%; max-width: 240px; }
.mark-grid span { aspect-ratio: 1; border-radius: 8px; display: grid; place-items: center; font-size: 0.72rem; font-weight: 800; color: var(--text-2); background: var(--surface-2); border: 1px solid var(--line); }
.mark-grid span.hl { color: #fff; background: rgba(76, 107, 255, 0.35); border-color: rgba(76, 107, 255, 0.6); }
.mark-grid span.cy { color: var(--abyss); background: var(--cyan); border-color: var(--cyan); }
.models-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: flex-end; gap: 16px; margin-bottom: 28px; }
.models-head .section-head { margin-bottom: 0; }
.step .mini { margin-top: 18px; border-radius: 12px; border: 1px solid var(--line); background: var(--abyss); padding: 12px 14px; font-size: 0.82rem; color: var(--text-2); display: flex; flex-direction: column; gap: 8px; }
.step .mini .r { display: flex; justify-content: space-between; gap: 10px; font-family: var(--font-mono); }
.step .mini .r b { color: var(--text); font-weight: 650; }
.step .mini .keyline { font-family: var(--font-mono); color: var(--text-3); letter-spacing: 0.08em; overflow-wrap: anywhere; }
@media (max-width: 1080px) { .feat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 900px) { .header-search { display: none; } .nav-mobile-only { display: block; } }
@media (max-width: 560px) { .feat-grid { grid-template-columns: minmax(0, 1fr); } .ticker a.more { display: none; } .lang-toggle { display: inline-flex; } .header-actions .btn-primary { display: none; } }

/* ---------- mobile: always-reachable sign-in / sign-up ---------- */
.mobile-cta { display: none; }
.data-note .badge { flex-shrink: 0; white-space: nowrap; }
@media (max-width: 900px) {
  .header-actions .btn-link { display: inline-flex; padding: 8px 6px; font-size: 0.92rem; }
  .mobile-cta {
    display: flex; gap: 10px; position: fixed; left: 0; right: 0; bottom: 0; z-index: 60;
    padding: 10px var(--gutter) calc(10px + env(safe-area-inset-bottom, 0px));
    background: rgba(8, 14, 26, 0.94); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px);
    border-top: 1px solid var(--line-2);
  }
  .mobile-cta .btn { flex: 1; min-height: 46px; }
  body { padding-bottom: calc(70px + env(safe-area-inset-bottom, 0px)); }
  #featured-models { grid-auto-flow: column; grid-template-columns: none; grid-auto-columns: minmax(280px, 82%); overflow-x: auto; scroll-snap-type: x mandatory; padding-bottom: 8px; scrollbar-width: thin; }
  #featured-models .model { scroll-snap-align: start; }
}
/* phone in landscape: header already shows both buttons, give the screen back */
@media (max-width: 900px) and (max-height: 500px) and (orientation: landscape) {
  .mobile-cta { display: none; }
  body { padding-bottom: 0; }
  .ticker { display: none; }
}
@media (max-width: 380px) {
  .brand img { height: 26px; }
  .lang-toggle button { padding: 4px 8px; }
}
.site-footer .beian { margin-top: 14px; display: flex; flex-wrap: wrap; justify-content: center; gap: 18px; font-size: 0.82rem; }
.site-footer .beian a { color: var(--text-3); }
.site-footer .beian a:hover { color: var(--text-2); }