:root {
  --bg: #0f0f14;
  --panel: #1a1a24;
  --panel-2: #1a1a1a;
  --panel-3: #14141c;
  --header-bg: rgba(15, 15, 20, 0.6);
  --menu-bg: rgba(15, 15, 20, 0.96);
  --dot: rgba(203, 213, 224, 0.14);
  --border: rgba(255, 255, 255, 0.05);
  --border-hi: rgba(255, 255, 255, 0.09);
  --text: #f3f4f6;
  --text-dim: #d1d5db;
  --text-mute: #90a1b9;
  --blue: #60a5fa;
  --blue-strong: #3b82f6;
  --violet: #a78bfa;
  --cyan: #38bdf8;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --maxw: 1180px;
  --font: "Geist", -apple-system, BlinkMacSystemFont, "PingFang SC", "Segoe UI", Arial, sans-serif;
  --mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --glow: radial-gradient(ellipse at 50% 0%, rgba(167, 139, 250, 0.18), rgba(56, 189, 248, 0.12) 45%, transparent 70%);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}
/* fixed atmospheric layers: dot grid + radial glows */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: -2;
  background-image: radial-gradient(var(--dot) 1px, transparent 1px);
  background-size: 28px 28px;
  -webkit-mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 75%);
  mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 75%);
  opacity: 0.5;
}
body::after {
  content: "";
  position: fixed; inset: 0; z-index: -3;
  background:
    radial-gradient(circle at 50% 8%, rgba(59, 130, 246, 0.10), transparent 34%),
    radial-gradient(circle at 50% 96%, rgba(255, 255, 255, 0.04), transparent 30%);
}

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.gradient-text {
  background: linear-gradient(135deg, #ffffff 0%, #a5b4fc 50%, #ffffff 100%);
  -webkit-background-clip: text; background-clip: text;
  color: transparent;
}
.gradient-text.cyan {
  background: linear-gradient(135deg, #ffffff 0%, #67e8f9 45%, #ffffff 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}

/* ---------- NAV ---------- */
header {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  background: var(--header-bg);
  border-bottom: 1px solid var(--border);
}
nav { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 18px; letter-spacing: 0.3px; }
.brand img { height: 30px; width: auto; }
.nav-links { display: flex; gap: 34px; font-size: 14.5px; color: var(--text-dim); }
.nav-links a { transition: color 0.2s; position: relative; }
.nav-links a:hover { color: var(--text); }
.nav-links a.active { color: var(--text); }
.nav-links a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -6px; height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, var(--violet), var(--cyan));
}
.nav-cta { display: flex; align-items: center; gap: 14px; }

.btn {
  font-family: var(--font); font-size: 14.5px; font-weight: 500;
  padding: 10px 20px; border-radius: 999px; cursor: pointer;
  border: 1px solid var(--border-hi); background: transparent; color: var(--text);
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s, background 0.2s;
  white-space: nowrap;
}
.btn:hover { border-color: rgba(0, 123, 255, 0.5); box-shadow: 0 0 22px rgba(0, 123, 255, 0.18); }
.btn-primary {
  background: linear-gradient(135deg, var(--violet), var(--cyan));
  color: #0b0b10; font-weight: 600; border: none;
}
.btn-primary:hover { box-shadow: 0 0 28px rgba(110, 180, 255, 0.35); transform: translateY(-1px); }
.nav-toggle { display: none; background: none; border: none; color: var(--text); cursor: pointer; }

/* ---------- HERO ---------- */
.hero { text-align: center; padding: 110px 0 70px; position: relative; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--mono); font-size: 12.5px; letter-spacing: 0.5px;
  color: var(--blue); border: 1px solid var(--border-hi);
  padding: 6px 14px; border-radius: 999px; margin-bottom: 26px;
  background: rgba(96, 165, 250, 0.06);
}
.eyebrow .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 10px var(--cyan); }
.hero h1 { font-size: clamp(40px, 7vw, 76px); font-weight: 700; line-height: 1.05; letter-spacing: -1.5px; }
.hero .sub { margin: 22px auto 0; max-width: 620px; font-size: clamp(15px, 2vw, 18px); color: var(--text-dim); }
.hero-actions { margin-top: 36px; display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero-visual { margin: 60px auto 0; max-width: 880px; position: relative; }
.hero-visual img { width: 100%; border-radius: var(--radius-lg); }
.hero-visual::before {
  content: ""; position: absolute; inset: -10% 10% auto; height: 70%;
  background: var(--glow); filter: blur(40px); z-index: -1;
}

/* ---------- SECTION SHELL ---------- */
section { padding: 90px 0; }
.section-head { max-width: 680px; margin: 0 auto 56px; text-align: center; }
.section-head .tag { font-family: var(--mono); font-size: 12.5px; color: var(--blue); letter-spacing: 1px; text-transform: uppercase; }
.section-head h2 { font-size: clamp(28px, 4.5vw, 44px); font-weight: 700; margin: 14px 0 16px; letter-spacing: -0.8px; }
.section-head p { color: var(--text-dim); font-size: 16px; }

/* ---------- FEATURE GRID ---------- */
.grid { display: grid; gap: 20px; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.card {
  background: linear-gradient(180deg, var(--panel), var(--panel-3));
  border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: 30px 28px; transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
  position: relative; overflow: hidden;
}
.card::after {
  content: ""; position: absolute; inset: 0; border-radius: inherit; pointer-events: none;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.04) 0%, transparent 45%);
}
.card:hover { transform: translateY(-5px); border-color: rgba(96, 165, 250, 0.35); box-shadow: 0 14px 40px rgba(0, 0, 0, 0.45); }
.card .ico {
  width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center;
  background: rgba(96, 165, 250, 0.1); border: 1px solid var(--border-hi); color: var(--blue); margin-bottom: 18px;
}
.card h3 { font-size: 19px; font-weight: 600; margin-bottom: 10px; }
.card p { color: var(--text-mute); font-size: 14.5px; }

/* ---------- SPECS STRIP ---------- */
.specs { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.spec {
  text-align: center; padding: 36px 20px; border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--panel), var(--panel-3)); border: 1px solid var(--border);
}
.spec .num { font-family: var(--mono); font-size: clamp(30px, 5vw, 44px); font-weight: 500; }
.spec .lbl { color: var(--text-mute); font-size: 14px; margin-top: 6px; }

/* ---------- LIGHT STRIP / PROTOCOL ---------- */
.split { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.split img { width: 100%; border-radius: var(--radius-lg); border: 1px solid var(--border); }
.chips { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 28px; }
.chip {
  display: flex; align-items: center; gap: 12px; padding: 14px 16px;
  border: 1px solid var(--border); border-radius: var(--radius-sm); background: var(--panel-2);
}
.chip .led { width: 12px; height: 12px; border-radius: 50%; flex: none; }
.chip .meta b { display: block; font-size: 14.5px; font-weight: 600; }
.chip .meta span { font-size: 12.5px; color: var(--text-mute); }
.led.blue { background: #3b82f6; box-shadow: 0 0 10px #3b82f6; }
.led.green { background: #22c55e; box-shadow: 0 0 10px #22c55e; }
.led.orange { background: #fb923c; box-shadow: 0 0 10px #fb923c; }
.led.rgb { background: linear-gradient(90deg, #ff4d4d, #ffd24d, #4dff88, #4dd2ff, #b04dff); }

/* ---------- CTA ---------- */
.cta-box {
  text-align: center; padding: 72px 28px; border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 50% 0%, rgba(59, 130, 246, 0.16), transparent 60%),
    linear-gradient(180deg, var(--panel), var(--panel-3));
  border: 1px solid var(--border-hi); position: relative; overflow: hidden;
}
.cta-box h2 { font-size: clamp(28px, 4.5vw, 42px); font-weight: 700; letter-spacing: -0.8px; }
.cta-box p { color: var(--text-dim); margin: 16px auto 30px; max-width: 540px; }

/* ---------- FOOTER ---------- */
footer { border-top: 1px solid var(--border); padding: 56px 0 40px; margin-top: 40px; }
.foot { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 32px; align-items: flex-start; }
.foot .brand { margin-bottom: 14px; }
.foot p { color: var(--text-mute); font-size: 14px; max-width: 320px; }
.socials { display: flex; gap: 16px; }
.socials a {
  width: 96px; border: 1px solid var(--border); border-radius: var(--radius-sm);
  overflow: hidden; background: #fff; transition: border-color 0.2s, transform 0.2s;
}
.socials a:hover { border-color: rgba(96, 165, 250, 0.4); transform: translateY(-3px); }
.socials img { width: 100%; height: 96px; object-fit: cover; }
.copyright { text-align: center; color: var(--text-mute); font-size: 13px; margin-top: 40px; border-top: 1px solid var(--border); padding-top: 24px; }

/* 备案信息 */
.beian { text-align: center; margin-top: 14px; display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 6px 18px; font-size: 12px; color: var(--text-mute); }
.beian a { color: inherit; text-decoration: none; transition: color .2s ease; }
.beian a:hover { color: var(--text); }
.beian .beian-gongan { display: inline-flex; align-items: center; gap: 5px; }
.beian .beian-gongan img { width: 16px; height: 16px; vertical-align: middle; display: inline-block; }
.beian .sep { color: var(--border); margin: 0 4px; opacity: .6; }

/* ---------- BOOKING MODAL ---------- */
.modal { position: fixed; inset: 0; z-index: 100; display: flex; align-items: center; justify-content: center; opacity: 0; pointer-events: none; transition: opacity 0.25s; }
.modal.open { opacity: 1; pointer-events: auto; }
.modal-backdrop { position: absolute; inset: 0; background: rgba(0, 0, 0, 0.72); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); }
.modal-panel {
  position: relative; width: min(680px, 92vw); padding: 38px; border-radius: var(--radius-lg);
  background: linear-gradient(180deg, var(--panel), var(--panel-3)); border: 1px solid var(--border-hi);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.6);
  transform: translateY(16px) scale(0.98); transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
}
.modal.open .modal-panel { transform: none; }
.modal-close {
  position: absolute; top: 16px; right: 18px; width: 36px; height: 36px; border-radius: 50%;
  border: 1px solid var(--border); background: transparent; color: var(--text-mute);
  font-size: 24px; line-height: 1; cursor: pointer; display: grid; place-items: center;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.modal-close:hover { color: var(--text); border-color: var(--border-hi); background: rgba(255, 255, 255, 0.05); }
.modal-panel h2 { font-size: clamp(24px, 4vw, 32px); font-weight: 700; margin-bottom: 10px; }
.modal-panel > p { color: var(--text-mute); margin-bottom: 28px; }
.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.qr-card {
  background: #fff; border-radius: var(--radius-md); padding: 18px; border: 1px solid var(--border);
  transition: transform 0.25s, box-shadow 0.25s;
}
.qr-card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(0, 0, 0, 0.35); }
.qr-card img { width: 100%; border-radius: 10px; }
.qr-card span { display: block; margin-top: 14px; color: #111; font-weight: 600; font-size: 15px; }

@media (max-width: 560px) {
  .qr-grid { grid-template-columns: 1fr; }
  .modal-panel { padding: 28px 22px; }
}

/* ---------- MULTI-PAGE (page hero / entries / breadcrumb) ---------- */
.page-hero { text-align: center; padding: 96px 0 36px; position: relative; }
.page-hero .eyebrow { margin-bottom: 20px; }
.page-hero h1 { font-size: clamp(34px, 6vw, 60px); font-weight: 700; line-height: 1.08; letter-spacing: -1.2px; }
.page-hero .sub { margin: 18px auto 0; max-width: 640px; font-size: clamp(15px, 2vw, 18px); color: var(--text-dim); }

/* ---------- GUIDE HERO STATS + ANCHOR CHIPS ---------- */
.guide-stats {
  display: inline-flex; align-items: center; gap: 18px;
  margin: 28px auto 0; padding: 10px 18px;
  border: 1px solid var(--border); border-radius: 999px;
  background: linear-gradient(180deg, var(--panel), var(--panel-2));
  box-shadow: 0 1px 0 rgba(255,255,255,.04) inset, 0 6px 18px rgba(0,0,0,.18);
  font-family: var(--mono);
}
.guide-stats .gs-item { display: inline-flex; align-items: baseline; gap: 6px; font-size: 13px; color: var(--text-mute); }
.guide-stats .gs-item strong { color: var(--text); font-size: 18px; font-weight: 600; letter-spacing: -0.3px; }
.guide-stats .gs-item i { font-style: normal; letter-spacing: .4px; }
.guide-stats .gs-sep { width: 1px; height: 14px; background: var(--border); }

.guide-anchors {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 8px;
  margin: 22px auto 0; max-width: 720px;
}
.guide-anchors a {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 14px; border-radius: 999px;
  font-size: 13.5px; color: var(--text-dim); text-decoration: none;
  background: var(--panel-2); border: 1px solid var(--border);
  transition: color .2s, border-color .2s, background .2s, transform .2s;
}
.guide-anchors a:hover {
  color: var(--text); border-color: rgba(96,165,250,.45);
  background: linear-gradient(135deg, rgba(96,165,250,.08), rgba(167,139,250,.06));
  transform: translateY(-1px);
}
.guide-anchors a:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
.entry-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; }
.entry-card {
  display: flex; flex-direction: column; gap: 12px; padding: 30px 28px;
  background: linear-gradient(180deg, var(--panel), var(--panel-3));
  border: 1px solid var(--border); border-radius: var(--radius-md);
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s; position: relative; overflow: hidden;
}
.entry-card::after {
  content: ""; position: absolute; inset: 0; border-radius: inherit; pointer-events: none;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.04) 0%, transparent 45%);
}
.entry-card:hover { transform: translateY(-5px); border-color: rgba(96, 165, 250, 0.35); box-shadow: 0 14px 40px rgba(0, 0, 0, 0.45); }
.entry-card .ec-ico {
  width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center;
  background: rgba(96, 165, 250, 0.1); border: 1px solid var(--border-hi); color: var(--blue); margin-bottom: 6px;
}
.entry-card h3 { font-size: 19px; font-weight: 600; }
.entry-card p { color: var(--text-mute); font-size: 14.5px; flex: 1; }
.entry-card .ec-link { font-size: 14px; color: var(--cyan); display: inline-flex; align-items: center; gap: 4px; margin-top: 4px; }
.entry-card .ec-link::after { content: "\2192"; transition: transform 0.2s; }
.entry-card:hover .ec-link::after { transform: translateX(4px); }

.breadcrumb { font-size: 13.5px; color: var(--text-mute); margin-bottom: 28px; }
.breadcrumb a { color: var(--blue); }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb span { color: var(--text-mute); margin: 0 8px; }

/* ---------- REVEAL ANIMATION ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1); will-change: opacity, transform; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- USER GUIDE ---------- */
.guide-intro { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-top: 8px; }
.guide-feat {
  display: flex; gap: 14px; align-items: flex-start; padding: 20px;
  border: 1px solid var(--border); border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--panel), var(--panel-3));
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}
.guide-feat:hover { transform: translateY(-4px); border-color: rgba(96, 165, 250, 0.35); box-shadow: 0 12px 34px rgba(0, 0, 0, 0.45); }
.guide-feat .gf-ico { font-size: 22px; line-height: 1.2; flex: none; }
.guide-feat h4 { font-size: 15.5px; font-weight: 600; margin-bottom: 4px; }
.guide-feat p { font-size: 13.5px; color: var(--text-mute); }

.callout {
  margin: 44px 0; padding: 26px 28px; border: 1px solid var(--border-hi); border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(167, 139, 250, 0.07), rgba(56, 189, 248, 0.05));
}
.callout h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.callout p { color: var(--text-dim); font-size: 15px; }
.callout strong { color: var(--text); }

.video-banner {
  display: flex; align-items: center; gap: 24px; flex-wrap: wrap;
  padding: 28px; border: 1px solid var(--border-hi); border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--panel), var(--panel-3));
}
.video-banner .vb-play {
  width: 64px; height: 64px; border-radius: 50%; flex: none; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--violet), var(--cyan)); color: #0b0b10;
  box-shadow: 0 0 24px rgba(110, 180, 255, 0.3);
}
.video-banner h3 { font-size: 20px; font-weight: 700; }
.video-banner p { color: var(--text-mute); font-size: 14px; margin-top: 4px; }
.video-banner .btn { margin-left: auto; }

.guide-cat { font-size: 13px; font-family: var(--mono); letter-spacing: 1px; color: var(--blue); text-transform: uppercase; margin: 48px 0 18px; }
.guide-cat:first-of-type { margin-top: 8px; }
.doc-card {
  display: flex; flex-direction: column; gap: 8px; padding: 22px;
  border: 1px solid var(--border); border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--panel), var(--panel-3));
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}
.doc-card:hover { transform: translateY(-4px); border-color: rgba(96, 165, 250, 0.35); box-shadow: 0 12px 34px rgba(0, 0, 0, 0.45); }
.doc-card .dc-ico { font-size: 24px; }
.doc-card h4 { font-size: 16px; font-weight: 600; }
.doc-card p { font-size: 13.5px; color: var(--text-mute); flex: 1; }
.doc-card .dc-link { font-size: 13.5px; color: var(--cyan); display: inline-flex; align-items: center; gap: 4px; margin-top: 2px; }
.doc-card .dc-link::after { content: "\2192"; }

.video-group { margin-top: 6px; }
.video-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 12px; }
.video-item {
  display: flex; align-items: center; gap: 10px; padding: 14px 16px;
  border: 1px solid var(--border); border-radius: var(--radius-sm); background: var(--panel-2);
  font-size: 14px; transition: border-color 0.2s, transform 0.2s;
}
.video-item:hover { border-color: rgba(96, 165, 250, 0.35); transform: translateY(-2px); }
.video-item .vi-ico { font-size: 18px; flex: none; }
.video-item .vi-dur { margin-left: auto; font-family: var(--mono); font-size: 12px; color: var(--text-mute); }

@media (max-width: 720px) {
  .video-banner .btn { margin-left: 0; width: 100%; text-align: center; }
}

/* ---------- GUIDE CONTROLS (dynamic) ---------- */
.guide-controls { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin: 40px 0 4px; }
.guide-tabs { display: inline-flex; padding: 4px; gap: 4px; background: var(--panel-2); border: 1px solid var(--border); border-radius: 999px; }
.guide-tab {
  font-family: var(--font); font-size: 14px; font-weight: 500; color: var(--text-mute);
  padding: 8px 18px; border-radius: 999px; cursor: pointer; border: none; background: transparent;
  transition: color 0.2s, background 0.2s;
}
.guide-tab.active { color: #0b0b10; background: linear-gradient(135deg, var(--violet), var(--cyan)); font-weight: 600; }
.guide-search {
  flex: 1; min-width: 200px; display: flex; align-items: center; gap: 8px; padding: 9px 16px;
  background: var(--panel-2); border: 1px solid var(--border); border-radius: 999px;
}
.guide-search input { flex: 1; background: transparent; border: none; outline: none; color: var(--text); font-family: var(--font); font-size: 14px; }
.guide-search input::placeholder { color: var(--text-mute); }
.guide-search svg { color: var(--text-mute); flex: none; }
.guide-empty { text-align: center; color: var(--text-mute); padding: 48px 0; font-size: 15px; }

/* ---------- DOC DETAIL PAGES ---------- */
.doc-card-link { color: inherit; text-decoration: none; display: flex; }
.doc-card-link .doc-card { flex: 1; width: 100%; }
.guide-cat + .grid .doc-card-link:first-child { margin-top: 0; }

.doc-article {
  max-width: 820px; margin: 0 auto; padding: 8px 0 8px;
}
.doc-article .lead {
  font-size: 17px; color: var(--text-dim); margin-bottom: 36px;
  padding: 20px 24px; border-left: 3px solid var(--blue);
  background: linear-gradient(135deg, rgba(96, 165, 250, 0.06), transparent);
  border-radius: 0 12px 12px 0;
}
.doc-section { margin-bottom: 38px; }
.doc-section h2 {
  font-size: clamp(22px, 3vw, 28px); font-weight: 700; letter-spacing: -0.5px; margin-bottom: 14px;
  display: flex; align-items: center; gap: 10px;
}
.doc-section h2::before {
  content: ""; width: 8px; height: 22px; border-radius: 4px;
  background: linear-gradient(180deg, var(--violet), var(--cyan)); flex: none;
}
.doc-section > p { color: var(--text-dim); font-size: 15.5px; margin-bottom: 14px; }
.doc-steps { list-style: none; counter-reset: step; display: grid; gap: 12px; margin: 6px 0 4px; }
.doc-steps li {
  counter-increment: step; position: relative; padding: 16px 18px 16px 56px;
  border: 1px solid var(--border); border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--panel), var(--panel-3));
  font-size: 15px; color: var(--text-dim);
  transition: border-color 0.2s, transform 0.2s;
}
.doc-steps li:hover { border-color: rgba(96, 165, 250, 0.3); transform: translateX(2px); }
.doc-steps li::before {
  content: counter(step); position: absolute; left: 16px; top: 14px;
  width: 28px; height: 28px; border-radius: 50%; display: grid; place-items: center;
  font-family: var(--mono); font-size: 13px; font-weight: 600; color: #0b0b10;
  background: linear-gradient(135deg, var(--violet), var(--cyan));
}
.doc-steps li b { color: var(--text); font-weight: 600; }
.doc-tip {
  margin-top: 10px; padding: 16px 18px; border-radius: var(--radius-md);
  border: 1px solid rgba(56, 189, 248, 0.25);
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.08), rgba(167, 139, 250, 0.05));
  font-size: 14.5px; color: var(--text-dim);
}
.doc-tip b { color: var(--cyan); }
.doc-source {
  max-width: 820px; margin: 8px auto 0; padding: 14px 18px; border-radius: var(--radius-sm);
  border: 1px dashed var(--border-hi); background: var(--panel-2);
  font-size: 13px; color: var(--text-mute); text-align: center;
}
.doc-nav {
  max-width: 820px; margin: 40px auto 0; display: flex; align-items: center; justify-content: space-between;
  gap: 14px; flex-wrap: wrap;
}
.doc-nav a {
  padding: 12px 18px; border: 1px solid var(--border); border-radius: 999px;
  font-size: 14px; color: var(--text-dim); transition: border-color 0.2s, color 0.2s, transform 0.2s;
}
.doc-nav a:hover { border-color: rgba(96, 165, 250, 0.4); color: var(--text); transform: translateY(-2px); }
.doc-nav .doc-prev::before { content: "← "; color: var(--cyan); }
.doc-nav .doc-next::after { content: " →"; color: var(--cyan); }
.doc-nav .doc-back { color: var(--blue); border-color: rgba(96, 165, 250, 0.25); }

@media (max-width: 560px) {
  .doc-nav { flex-direction: column; align-items: stretch; }
  .doc-nav a { text-align: center; }
}

/* 文档正文内容（由飞书真实内容渲染） */
.doc-article h2, .doc-article h3, .doc-article h4 {
  font-weight: 700; letter-spacing: -0.4px; margin: 34px 0 14px;
  display: flex; align-items: center; gap: 10px; line-height: 1.3;
}
.doc-article h2 { font-size: clamp(21px, 2.6vw, 26px); }
.doc-article h3 { font-size: clamp(18px, 2.2vw, 21px); }
.doc-article h4 { font-size: clamp(16px, 1.8vw, 18px); color: var(--text); }
.doc-article h2::before, .doc-article h3::before, .doc-article h4::before {
  content: ""; width: 8px; height: 22px; border-radius: 4px; flex: none;
  background: linear-gradient(180deg, var(--violet), var(--cyan));
}
.doc-article > p, .doc-article li > p {
  color: var(--text-dim); font-size: 15.5px; line-height: 1.85; margin: 0 0 14px;
}
.doc-article p b, .doc-article li b { color: var(--text); font-weight: 600; }
.doc-ul, .doc-ol { margin: 0 0 18px; padding-left: 4px; display: grid; gap: 10px; }
.doc-ul { list-style: none; }
.doc-ol { list-style: none; counter-reset: olstep; }
.doc-ul > li, .doc-ol > li {
  position: relative; padding: 14px 16px 14px 44px; font-size: 15px; color: var(--text-dim);
  border: 1px solid var(--border); border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--panel), var(--panel-3)); line-height: 1.75;
  transition: border-color .2s, transform .2s;
}
.doc-ul > li:hover, .doc-ol > li:hover { border-color: rgba(96,165,250,.3); transform: translateX(2px); }
.doc-ul > li::before {
  content: ""; position: absolute; left: 18px; top: 20px; width: 8px; height: 8px; border-radius: 50%;
  background: linear-gradient(135deg, var(--violet), var(--cyan)); flex: none;
}
.doc-ol > li { counter-increment: olstep; }
.doc-ol > li::before {
  content: counter(olstep); position: absolute; left: 14px; top: 14px;
  width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center;
  font-family: var(--mono); font-size: 12.5px; font-weight: 600; color: #0b0b10;
  background: linear-gradient(135deg, var(--violet), var(--cyan));
}
.doc-quote {
  margin: 0 0 18px; padding: 16px 18px; border-left: 3px solid var(--cyan); border-radius: 0 12px 12px 0;
  background: linear-gradient(135deg, rgba(56,189,248,.07), transparent); color: var(--text-dim); font-size: 15px;
}
.doc-hr { border: none; height: 1px; margin: 30px 0; background: linear-gradient(90deg, transparent, var(--border-hi), transparent); }
.doc-fig { margin: 22px 0; text-align: center; }
.doc-fig img {
  max-width: 100%; border-radius: var(--radius-md); border: 1px solid var(--border);
  box-shadow: 0 12px 40px rgba(0,0,0,.45); background: #fff; cursor: zoom-in;
  transition: transform .25s, box-shadow .25s;
}
.doc-fig img:hover { transform: scale(1.012); box-shadow: 0 16px 52px rgba(0,0,0,.55); }
.doc-fig figcaption { margin-top: 10px; font-size: 13px; color: var(--text-mute); }
.doc-table { width: 100%; border-collapse: collapse; margin: 18px 0; font-size: 14.5px; overflow: hidden; border-radius: var(--radius-md); }
.doc-table th, .doc-table td { border: 1px solid var(--border); padding: 11px 14px; text-align: left; color: var(--text-dim); vertical-align: top; }
.doc-table th { background: var(--panel-2); color: var(--text); font-weight: 600; }
.doc-table tr:nth-child(even) td { background: rgba(255,255,255,.02); }
.doc-code { margin: 16px 0; padding: 16px 18px; border-radius: var(--radius-md); background: #0c0c12; border: 1px solid var(--border); overflow-x: auto; }
.doc-code code { font-family: var(--mono); font-size: 13.5px; color: #cfe3ff; white-space: pre; }
.doc-note { padding: 12px 16px; border-radius: var(--radius-sm); background: var(--panel-2); border: 1px dashed var(--border-hi); font-size: 14px; color: var(--text-mute); margin: 0 0 14px; }
.doc-img-fallback { padding: 14px 16px; border-radius: var(--radius-sm); background: var(--panel-2); border: 1px dashed var(--border-hi); font-size: 14px; color: var(--text-mute); font-style: italic; }

/* ---------- RESPONSIVE ---------- */
@media (max-width: 860px) {
  .split { grid-template-columns: 1fr; gap: 32px; }
  .specs { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex; flex-direction: column; gap: 4px; position: absolute; top: 68px; left: 0; right: 0;
    background: var(--menu-bg); backdrop-filter: blur(16px); padding: 14px 24px; border-bottom: 1px solid var(--border);
  }
  .nav-links.open a { padding: 10px 0; }
  .nav-links.open a.active::after { display: none; }
  .hero { padding: 76px 0 50px; }
  section { padding: 64px 0; }
  .chips { grid-template-columns: 1fr; }
  .socials { width: 100%; }
  .guide-controls { flex-direction: column; align-items: stretch; }
  .guide-tabs { width: 100%; }
}

/* ============ THEME: light ============ */
[data-theme="light"] {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --panel-2: #eef1f7;
  --panel-3: #e6eaf2;
  --border: rgba(15, 23, 42, 0.08);
  --border-hi: rgba(15, 23, 42, 0.14);
  --text: #13151c;
  --text-dim: #3f4655;
  --text-mute: #6b7280;
  --header-bg: rgba(245, 247, 251, 0.72);
  --menu-bg: rgba(245, 247, 251, 0.98);
  --dot: rgba(30, 41, 70, 0.10);
  --glow: radial-gradient(ellipse at 50% 0%, rgba(99, 102, 241, 0.14), rgba(56, 189, 248, 0.10) 45%, transparent 70%);
}
[data-theme="light"] body::after {
  background:
    radial-gradient(circle at 50% 8%, rgba(59, 130, 246, 0.08), transparent 34%),
    radial-gradient(circle at 50% 96%, rgba(99, 102, 241, 0.05), transparent 30%);
}
[data-theme="light"] .gradient-text {
  background: linear-gradient(135deg, #1e293b 0%, #6d28d9 50%, #1e293b 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
[data-theme="light"] .gradient-text.cyan {
  background: linear-gradient(135deg, #0f172a 0%, #0891b2 45%, #0f172a 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
[data-theme="light"] .card::after,
[data-theme="light"] .entry-card::after { background: linear-gradient(135deg, rgba(15,23,42,0.03) 0%, transparent 45%); }
[data-theme="light"] .doc-table tr:nth-child(even) td { background: rgba(15, 23, 42, 0.035); }

/* theme transition only while switching (no initial-load flash) */
html.theme-transition *, html.theme-transition *::before, html.theme-transition *::after {
  transition: background-color .4s ease, color .4s ease, border-color .4s ease, box-shadow .4s ease !important;
}

/* ============ THEME SWITCH UI ============ */
.theme-switch {
  display: inline-flex; align-items: center; gap: 2px; padding: 3px;
  border-radius: 999px; border: 1px solid var(--border); background: var(--panel-2);
}
.theme-opt {
  width: 30px; height: 30px; border: none; background: transparent; color: var(--text-mute);
  border-radius: 999px; cursor: pointer; display: grid; place-items: center; font-size: 14px; line-height: 1;
  transition: color .2s, background .2s, transform .2s;
}
.theme-opt:hover { color: var(--text); }
.theme-opt.active { color: #0b0b10; background: linear-gradient(135deg, var(--violet), var(--cyan)); }
@media (max-width: 720px) {
  .nav-cta { gap: 10px; }
  .theme-opt { width: 28px; height: 28px; }
}

/* ---------- SKIP LINK (a11y) ---------- */
.skip-link {
  position: fixed; left: 16px; top: -64px; z-index: 200;
  padding: 10px 18px; border-radius: 999px;
  background: linear-gradient(135deg, var(--violet), var(--cyan)); color: #0b0b10;
  font-weight: 600; font-size: 14px; transition: top .2s ease;
}
.skip-link:focus { top: 16px; outline: 2px solid var(--cyan); outline-offset: 2px; }

/* ============ REDUCED MOTION ============ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1 !important; transform: none !important; }
}

/* ---------- HERO CANVAS (Three.js immersive bg) ---------- */
#hero-canvas {
  position: absolute; inset: 0; width: 100%; height: 100%;
  z-index: -1; pointer-events: none; opacity: 0.9;
}