@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&family=Syne:wght@400;600;700;800&family=DM+Sans:ital,opsz,wght@0,9..40,400;0,9..40,500;0,9..40,600;0,9..40,700&display=swap');

/* ─────────────────────────────────────────── TOKENS */
:root {
  --bg:        #060A0F;
  --bg-2:      #0C1220;
  --bg-card:   #0E1828;
  --bg-code:   #080F1C;
  --bg-nav:    rgba(6,10,15,0.9);
  --border:    rgba(255,255,255,0.07);
  --border-hi: rgba(0,212,180,0.28);
  --border-2:  rgba(91,140,255,0.22);
  --text:      #DDE6F5;
  --text-muted:#7A90AA;
  --text-dim:  #3A4E68;
  --accent:    #00D4B4;
  --accent-d:  rgba(0,212,180,0.1);
  --accent-g:  rgba(0,212,180,0.2);
  --blue:      #5B8CFF;
  --blue-d:    rgba(91,140,255,0.1);
  --r:         10px;
  --r-lg:      16px;
  --r-xl:      22px;
  --f:         'Noto Sans SC','PingFang SC','Hiragino Sans GB',system-ui,sans-serif;
  --f-en:      'DM Sans','Noto Sans SC',system-ui,sans-serif;
  --f-mono:    'JetBrains Mono','Fira Code',monospace;
  --f-d:       'Syne','DM Sans',sans-serif;
  --nav-h:     62px;
}

/* ─────────────────────────────────────────── RESET */
*,*::before,*::after { box-sizing:border-box; margin:0; padding:0; }
html { scroll-behavior:smooth; scroll-padding-top:80px; }
body {
  font-family:var(--f); background:var(--bg); color:var(--text);
  font-size:15px; line-height:1.78; min-height:100vh; overflow-x:hidden;
}

/* ─────────────────────────────────────────── LANGUAGE */
.zh-only  { display:initial; }
.en-only  { display:none !important; }
.zh-block { display:block; }
.en-block { display:none !important; }
.zh-li    { display:list-item; }
.en-li    { display:none !important; }

html.lang-en .zh-only  { display:none !important; }
html.lang-en .en-only  { display:initial !important; }
html.lang-en .zh-block { display:none !important; }
html.lang-en .en-block { display:block !important; }
html.lang-en .zh-li    { display:none !important; }
html.lang-en .en-li    { display:list-item !important; }
html.lang-en body      { font-family:var(--f-en); }

/* ─────────────────────────────────────────── BACKGROUND */
body::before {
  content:''; position:fixed; inset:0; pointer-events:none; z-index:0;
  background:
    radial-gradient(ellipse 80% 50% at 50% -5%, rgba(0,212,180,0.06) 0%, transparent 65%),
    radial-gradient(ellipse 40% 40% at 92% 82%, rgba(91,140,255,0.04) 0%, transparent 50%);
}
body::after {
  content:''; position:fixed; inset:0; pointer-events:none; z-index:0; opacity:.45;
  background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.028'/%3E%3C/svg%3E");
}

/* ─────────────────────────────────────────── NAV */
nav {
  position:fixed; top:0; left:0; right:0; z-index:200;
  height:var(--nav-h);
  background:var(--bg-nav);
  backdrop-filter:blur(24px) saturate(160%);
  border-bottom:1px solid var(--border);
}
nav::after {
  content:''; position:absolute; bottom:-1px; left:0; right:0; height:1px;
  background:linear-gradient(90deg, transparent 0%, var(--accent) 35%, var(--blue) 65%, transparent 100%);
  opacity:.2;
}

.nav-inner {
  max-width:1160px; width:100%; margin:0 auto; height:100%;
  padding:0 28px; display:flex; align-items:center; gap:6px;
}

.nav-logo {
  display:flex; align-items:center; gap:10px;
  text-decoration:none; flex-shrink:0; margin-right:10px;
}
.nav-logo-icon {
  width:32px; height:32px;
  background:linear-gradient(135deg, var(--accent) 0%, #00AABB 100%);
  border-radius:9px; display:flex; align-items:center; justify-content:center;
  font-size:14px; font-weight:800; color:#040810; font-family:var(--f-d);
  box-shadow:0 2px 12px rgba(0,212,180,0.28); flex-shrink:0;
}
.nav-logo-text {
  font-family:var(--f-d); font-weight:700; font-size:16px;
  color:#EEF4FF; letter-spacing:.01em;
}

.nav-links { display:flex; align-items:center; gap:2px; list-style:none; flex:1; }
.nav-links a {
  text-decoration:none; color:var(--text-muted); font-size:13.5px;
  padding:6px 12px; border-radius:7px;
  transition:color .14s, background .14s; font-weight:500; white-space:nowrap;
}
.nav-links a:hover { color:var(--text); background:rgba(255,255,255,0.055); }
.nav-links a.active { color:var(--accent); background:var(--accent-d); }

/* Language toggle */
.lang-toggle {
  display:flex; align-items:center;
  background:rgba(255,255,255,0.045); border:1px solid var(--border);
  border-radius:8px; padding:2px; gap:2px; flex-shrink:0; margin-left:8px;
}
.lang-btn {
  padding:5px 12px; border-radius:6px; font-size:12px; font-weight:700;
  cursor:pointer; border:none; background:transparent; color:var(--text-muted);
  transition:all .15s; font-family:var(--f-d); letter-spacing:.04em;
}
.lang-btn.active {
  background:var(--accent); color:#040810;
  box-shadow:0 2px 8px var(--accent-g);
}
.lang-btn:not(.active):hover { color:var(--text); background:rgba(255,255,255,0.07); }

.nav-cta { flex-shrink:0; margin-left:8px; }

/* ─────────────────────────────────────────── BUTTONS */
.btn {
  display:inline-flex; align-items:center; gap:7px;
  padding:9px 20px; border-radius:var(--r); font-size:13.5px;
  font-weight:600; cursor:pointer; text-decoration:none;
  transition:all .18s; border:none; line-height:1;
  font-family:var(--f);
}
html.lang-en .btn { font-family:var(--f-en); }
.btn-primary {
  background:var(--accent); color:#040810;
  box-shadow:0 2px 14px rgba(0,212,180,0.22);
}
.btn-primary:hover {
  background:#1EF2D0; transform:translateY(-1px);
  box-shadow:0 6px 24px rgba(0,212,180,0.3); text-decoration:none;
}
.btn-outline {
  background:transparent; color:var(--text); border:1px solid var(--border);
}
.btn-outline:hover {
  border-color:rgba(255,255,255,0.18); background:rgba(255,255,255,0.04);
  text-decoration:none;
}
.btn-sm { padding:6px 14px; font-size:12.5px; }

/* ─────────────────────────────────────────── LAYOUT */
.page-wrap { max-width:1160px; margin:0 auto; padding:0 28px; position:relative; z-index:1; }

.doc-layout {
  display:flex; gap:52px;
  padding-top:calc(var(--nav-h) + 36px);
  align-items:flex-start; padding-bottom:80px;
}

/* ─────────────────────────────────────────── TOC SIDEBAR */
.doc-toc {
  width:188px; flex-shrink:0; position:sticky;
  top:calc(var(--nav-h) + 22px);
}
.doc-toc h4 {
  font-size:10.5px; text-transform:uppercase; letter-spacing:.14em;
  color:var(--text-dim); margin-bottom:14px; font-weight:600; padding-left:10px;
}
.doc-toc ul { list-style:none; }
.doc-toc li { margin-bottom:1px; }
.doc-toc a {
  display:block; font-size:13px; color:var(--text-muted);
  text-decoration:none; padding:5px 10px; border-radius:6px;
  border-left:2px solid transparent; transition:all .14s; line-height:1.4;
}
.doc-toc a:hover { color:var(--text); border-left-color:var(--accent); background:rgba(255,255,255,0.04); }

.doc-content { flex:1; min-width:0; padding-top:12px; }

/* ─────────────────────────────────────────── TYPOGRAPHY */
h1,h2,h3,h4 { font-family:var(--f-d); font-weight:700; line-height:1.3; color:#EEF4FF; }
html.lang-en h1, html.lang-en h2, html.lang-en h3 { font-family:var(--f-d); }

h1 { font-size:1.85rem; margin-bottom:14px; }

h2 {
  font-size:1.25rem; margin:52px 0 16px;
  padding-bottom:12px; border-bottom:1px solid var(--border);
  position:relative;
}
h2:first-child { margin-top:0; }
h2::before {
  content:''; position:absolute; bottom:-1px; left:0;
  width:44px; height:2px; background:var(--accent); border-radius:2px;
}

h3 { font-size:1.02rem; margin:26px 0 10px; color:#C8D8EE; }

p { margin-bottom:14px; }
.lead { font-size:1rem; color:var(--text-muted); margin-bottom:28px; line-height:1.88; }

a { color:var(--accent); text-decoration:none; }
a:hover { text-decoration:underline; }
ul,ol { padding-left:20px; margin-bottom:14px; }
li { margin-bottom:7px; }
strong { color:#EEF4FF; font-weight:600; }

blockquote {
  border-left:3px solid var(--accent); background:var(--accent-d);
  padding:14px 18px; border-radius:0 var(--r) var(--r) 0;
  margin:20px 0; color:var(--text-muted); font-size:14px; line-height:1.72;
}
blockquote a { color:var(--accent); }

/* ─────────────────────────────────────────── CODE */
.code-block { position:relative; margin:18px 0 22px; }

.code-header {
  display:flex; align-items:center; justify-content:space-between;
  background:rgba(255,255,255,0.04); border:1px solid var(--border);
  border-bottom:none; border-radius:var(--r-lg) var(--r-lg) 0 0; padding:9px 16px;
}
.code-lang {
  font-size:11px; font-family:var(--f-mono); color:var(--text-dim);
  text-transform:uppercase; letter-spacing:.1em;
}
.copy-btn {
  font-size:11.5px; color:var(--text-dim); background:transparent;
  border:1px solid var(--border); border-radius:5px; padding:3px 10px;
  cursor:pointer; font-family:var(--f); transition:all .14s;
}
.copy-btn:hover { color:var(--text-muted); border-color:rgba(255,255,255,0.15); }
.copy-btn.copied { color:var(--accent); border-color:var(--border-hi); }

pre {
  background:var(--bg-code); border:1px solid var(--border);
  border-radius:var(--r-lg); padding:22px; overflow-x:auto;
}
.code-header + pre { border-radius:0 0 var(--r-lg) var(--r-lg); border-top:none; }

code {
  font-family:var(--f-mono); font-size:13.5px; line-height:1.72; color:#B8CDEA;
}
:not(pre)>code {
  background:rgba(255,255,255,0.07); border:1px solid var(--border);
  border-radius:5px; padding:1px 7px; font-size:12.5px; color:var(--accent);
}

/* Syntax highlight */
.kw  { color:#A78BFA; }
.str { color:#6EE7B7; }
.cm  { color:#3A4E68; font-style:italic; }
.fn  { color:#93C5FD; }
.cn  { color:#FCA5A5; }
.op  { color:#5A6E88; }
.num { color:#FDBA74; }

/* ─────────────────────────────────────────── CARDS */
.card {
  background:var(--bg-card); border:1px solid var(--border);
  border-radius:var(--r-lg); padding:24px;
  transition:border-color .2s, box-shadow .2s, transform .2s;
}
.card:hover {
  border-color:var(--border-hi);
  box-shadow:0 8px 32px rgba(0,0,0,0.28); transform:translateY(-2px);
}
.card h3 { margin:0 0 8px; font-size:.97rem; }
.card p  { margin:0; font-size:14px; color:var(--text-muted); }
.card-arrow {
  width:30px; height:30px; background:var(--accent-d); border:1px solid var(--border-hi);
  border-radius:8px; display:flex; align-items:center; justify-content:center;
  font-size:13px; color:var(--accent); margin-bottom:12px;
}
.card-grid {
  display:grid; grid-template-columns:repeat(auto-fill, minmax(250px,1fr));
  gap:16px; margin:20px 0;
}

/* ─────────────────────────────────────────── TABLE */
.table-wrap {
  overflow-x:auto; margin:16px 0 24px;
  border-radius:var(--r-lg); border:1px solid var(--border);
}
table { width:100%; border-collapse:collapse; font-size:14px; }
th {
  text-align:left; padding:11px 16px;
  background:rgba(255,255,255,0.03);
  border-bottom:1px solid var(--border);
  color:var(--text-muted); font-size:11.5px;
  text-transform:uppercase; letter-spacing:.09em; font-weight:600;
}
td { padding:12px 16px; border-bottom:1px solid rgba(255,255,255,0.04); }
tr:last-child td { border-bottom:none; }
tr:hover td { background:rgba(255,255,255,0.02); }

/* ─────────────────────────────────────────── STEPS */
.steps { display:flex; flex-direction:column; gap:0; margin:24px 0; }
.step-item {
  display:flex; gap:18px; position:relative;
}
.step-item:not(:last-child)::before {
  content:''; position:absolute; left:11px; top:32px;
  width:2px; height:calc(100% - 16px);
  background:linear-gradient(to bottom, rgba(0,212,180,.3), transparent);
}
.step-left { display:flex; flex-direction:column; align-items:center; padding-top:4px; }
.step-circle {
  width:24px; height:24px; border-radius:50%;
  background:var(--accent-d); border:2px solid var(--accent);
  display:flex; align-items:center; justify-content:center;
  font-size:11px; font-weight:700; color:var(--accent);
  font-family:var(--f-d); flex-shrink:0;
}
.step-body { flex:1; padding-bottom:28px; }
.step-body h3 { margin:0 0 10px; font-size:1rem; }

/* ─────────────────────────────────────────── BADGE */
.badge {
  display:inline-flex; align-items:center; gap:6px; padding:4px 12px;
  border-radius:20px; font-size:12px; font-weight:600; letter-spacing:.04em;
}
.badge-teal { background:var(--accent-d); color:var(--accent); border:1px solid var(--border-hi); }
.badge-blue { background:var(--blue-d); color:var(--blue); border:1px solid var(--border-2); }

/* ─────────────────────────────────────────── INFO BOX */
.info-box {
  background:var(--bg-card); border:1px solid var(--border);
  border-left:3px solid var(--accent);
  border-radius:0 var(--r) var(--r) 0;
  padding:16px 20px; margin:20px 0;
  font-size:14px; color:var(--text-muted); line-height:1.72;
}
.info-box.blue { border-left-color:var(--blue); }

/* ─────────────────────────────────────────── FAQ */
.faq-item {
  border:1px solid var(--border); border-radius:var(--r-lg);
  margin-bottom:10px; overflow:hidden; transition:border-color .2s;
}
.faq-item:hover { border-color:var(--border-hi); }
.faq-q {
  padding:16px 20px; cursor:pointer;
  display:flex; align-items:center; justify-content:space-between; gap:12px;
  font-weight:600; font-size:14.5px; color:var(--text); list-style:none; user-select:none;
}
.faq-q::-webkit-details-marker { display:none; }
.faq-toggle {
  width:24px; height:24px; border-radius:6px; background:var(--accent-d);
  border:1px solid var(--border-hi); display:flex; align-items:center;
  justify-content:center; color:var(--accent); font-size:16px; flex-shrink:0;
  transition:transform .2s, background .2s;
}
details[open] .faq-toggle { transform:rotate(45deg); background:var(--accent); color:#040810; }
.faq-a {
  padding:0 20px 18px; font-size:14px; color:var(--text-muted);
  line-height:1.75; border-top:1px solid var(--border);
}
.faq-a p { margin-bottom:10px; }
.faq-a p:last-child { margin-bottom:0; }

/* ─────────────────────────────────────────── HOMEPAGE */
.hero {
  padding:calc(var(--nav-h) + 88px) 0 110px;
  position:relative; z-index:1;
}
.hero-eyebrow {
  display:inline-flex; align-items:center; gap:8px;
  background:var(--accent-d); border:1px solid var(--border-hi);
  border-radius:20px; padding:5px 14px; font-size:12.5px;
  color:var(--accent); margin-bottom:28px; font-weight:500;
}
.hero-title {
  font-family:var(--f-d); font-size:clamp(2.4rem,5vw,4rem);
  font-weight:800; line-height:1.1; color:#F0F6FF;
  margin-bottom:22px; letter-spacing:-.025em;
}
.hero-title .t-accent { color:var(--accent); }
.hero-title .t-blue   { color:var(--blue); }
.hero-sub {
  font-size:1.05rem; color:var(--text-muted);
  max-width:500px; margin-bottom:38px; line-height:1.88;
}
.hero-btns { display:flex; gap:12px; flex-wrap:wrap; }

/* Arch */
.arch { display:flex; align-items:center; margin:68px 0 0; flex-wrap:wrap; }
.arch-box {
  background:var(--bg-card); border:1px solid var(--border);
  border-radius:var(--r); padding:12px 20px;
  font-size:13.5px; font-weight:500; color:var(--text-muted); text-align:center;
  transition:border-color .2s;
}
.arch-box:hover { border-color:var(--border-hi); }
.arch-box.hub {
  background:linear-gradient(135deg, rgba(0,212,180,0.12), rgba(91,140,255,0.09));
  border-color:rgba(0,212,180,0.3); color:var(--accent);
  font-weight:700; font-size:15px; padding:16px 28px;
}
.arch-hub-label { font-size:11px; color:var(--text-muted); font-weight:400; margin-top:2px; }
.arch-arrow { color:var(--text-dim); font-size:18px; padding:0 12px; }
.arch-targets { display:flex; flex-direction:column; gap:8px; }

/* Section */
.section-eyebrow {
  font-size:11.5px; text-transform:uppercase; letter-spacing:.14em;
  color:var(--accent); font-weight:600; margin-bottom:10px;
}
.section-title {
  font-family:var(--f-d); font-size:1.7rem; font-weight:700;
  color:#EEF4FF; margin-bottom:12px; letter-spacing:-.015em;
}
.section-sub { color:var(--text-muted); font-size:1rem; margin-bottom:36px; }

/* Models */
.model-grid {
  display:grid; grid-template-columns:repeat(auto-fill, minmax(200px,1fr));
  gap:12px; margin:28px 0;
}
.model-card {
  background:var(--bg-card); border:1px solid var(--border);
  border-radius:var(--r); padding:16px;
  display:flex; align-items:center; gap:12px;
  transition:border-color .2s, transform .18s;
}
.model-card:hover { border-color:var(--border-hi); transform:translateY(-2px); }
.model-logo {
  width:38px; height:38px; border-radius:9px;
  display:flex; align-items:center; justify-content:center;
  font-size:15px; font-weight:800; font-family:var(--f-d); flex-shrink:0;
}
.ml-o { background:linear-gradient(135deg,#10B981,#059669); color:#fff; }
.ml-c { background:linear-gradient(135deg,#F59E0B,#D97706); color:#fff; }
.ml-g { background:linear-gradient(135deg,#3B82F6,#2563EB); color:#fff; }
.ml-x { background:linear-gradient(135deg,#EF4444,#DC2626); color:#fff; }
.ml-m { background:linear-gradient(135deg,#8B5CF6,#7C3AED); color:#fff; }
.model-name { font-weight:600; font-size:13.5px; }
.model-desc { font-size:12px; color:var(--text-muted); }

/* Features */
.feat-grid {
  display:grid; grid-template-columns:repeat(auto-fill, minmax(290px,1fr));
  gap:18px; margin:28px 0;
}
.feat-card {
  background:var(--bg-card); border:1px solid var(--border);
  border-radius:var(--r-lg); padding:28px;
  transition:border-color .2s, transform .2s;
}
.feat-card:hover { border-color:var(--border-hi); transform:translateY(-3px); }
.feat-icon {
  width:44px; height:44px; border-radius:11px;
  display:flex; align-items:center; justify-content:center;
  font-size:20px; margin-bottom:16px;
}
.fi-teal   { background:var(--accent-d); box-shadow:0 0 0 1px var(--border-hi); }
.fi-blue   { background:var(--blue-d);   box-shadow:0 0 0 1px var(--border-2); }
.fi-yellow { background:rgba(255,184,48,0.1); box-shadow:0 0 0 1px rgba(255,184,48,0.2); }
.feat-card h3 { font-size:1rem; margin:0 0 8px; font-weight:600; }
.feat-card p  { font-size:14px; color:var(--text-muted); margin:0; line-height:1.72; }

/* CTA */
.cta-block {
  background:linear-gradient(135deg, rgba(0,212,180,0.08), rgba(91,140,255,0.07));
  border:1px solid rgba(0,212,180,0.16); border-radius:var(--r-xl);
  padding:60px 48px; text-align:center; margin:72px 0; position:relative; overflow:hidden;
}
.cta-block::before {
  content:''; position:absolute; top:-60px; left:50%; transform:translateX(-50%);
  width:400px; height:300px;
  background:radial-gradient(ellipse, rgba(0,212,180,0.08) 0%, transparent 70%);
  pointer-events:none;
}
.cta-block h2 { font-size:1.7rem; margin:0 0 12px; border:none; padding:0; }
.cta-block h2::before { display:none; }
.cta-block p { color:var(--text-muted); margin-bottom:28px; }
.cta-btns { display:flex; gap:12px; justify-content:center; flex-wrap:wrap; }

/* ─────────────────────────────────────────── FOOTER */
footer {
  border-top:1px solid var(--border); padding:32px 28px;
  text-align:center; font-size:13px; color:var(--text-dim);
  position:relative; z-index:1;
}
footer a { color:var(--text-muted); }
footer a:hover { color:var(--accent); text-decoration:none; }

/* ─────────────────────────────────────────── SCROLLBAR */
::-webkit-scrollbar { width:6px; height:6px; }
::-webkit-scrollbar-track { background:transparent; }
::-webkit-scrollbar-thumb { background:rgba(255,255,255,0.1); border-radius:3px; }
::-webkit-scrollbar-thumb:hover { background:rgba(255,255,255,0.18); }

/* ─────────────────────────────────────────── ANIMATIONS */
@keyframes fade-up { from { opacity:0; transform:translateY(14px); } to { opacity:1; transform:none; } }
.anim { animation:fade-up .5s ease both; }
.d1 { animation-delay:.07s; } .d2 { animation-delay:.14s; }
.d3 { animation-delay:.21s; } .d4 { animation-delay:.28s; }

/* ─────────────────────────────────────────── RESPONSIVE */
@media (max-width:900px) {
  .doc-toc { display:none; }
  .doc-layout { flex-direction:column; gap:0; }
}
@media (max-width:680px) {
  .nav-links { display:none; }
  .hero-title { font-size:2rem; }
  .cta-block { padding:36px 20px; }
  .page-wrap { padding:0 16px; }
  .nav-inner { padding:0 16px; }
}