:root{
    --font-sans:"Inter","Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,sans-serif;
    --font-mono:"SFMono-Regular","SF Mono","JetBrains Mono","Menlo","Consolas",ui-monospace,monospace;
    --bg:#F5F6FB; --bg-elev:#FFFFFF; --hero-1:#EAEEF8; --hero-2:#DFE5F3;
    --ink:#141A32; --ink-soft:#454E6E; --ink-mute:#727B99;
    --line:rgba(20,26,50,0.10); --line-2:rgba(20,26,50,0.06);
    --accent:#B86A11; --accent-fill:#E79A2E; --accent-soft:rgba(231,154,46,0.14); --jade:#0E7F63;
    --shadow:0 1px 2px rgba(20,26,50,.05),0 12px 32px -12px rgba(20,26,50,.18);
    --c-node-a:rgba(231,154,46,.85); --c-node-b:rgba(35,120,150,.55); --c-link:rgba(20,26,50,.14);
  }
  html[lang="zh"]{--font-sans:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Source Han Sans SC","Noto Sans SC","Segoe UI",system-ui,sans-serif}
  @media (prefers-color-scheme:dark){
    :root{
      --bg:#0E1428; --bg-elev:#161D34; --hero-1:#0B1022; --hero-2:#141C38;
      --ink:#E9ECF7; --ink-soft:#AEB6D0; --ink-mute:#7C86A6;
      --line:rgba(233,236,247,0.11); --line-2:rgba(233,236,247,0.06);
      --accent:#F5B44E; --accent-fill:#F5B44E; --accent-soft:rgba(245,180,78,0.13); --jade:#3FC7A6;
      --shadow:0 1px 2px rgba(0,0,0,.3),0 18px 40px -16px rgba(0,0,0,.55);
      --c-node-a:rgba(245,180,78,.9); --c-node-b:rgba(63,199,166,.5); --c-link:rgba(233,236,247,.12);
    }
  }
  :root[data-theme="light"]{
    --bg:#F5F6FB;--bg-elev:#FFFFFF;--hero-1:#EAEEF8;--hero-2:#DFE5F3;--ink:#141A32;--ink-soft:#454E6E;--ink-mute:#727B99;
    --line:rgba(20,26,50,0.10);--line-2:rgba(20,26,50,0.06);--accent:#B86A11;--accent-fill:#E79A2E;--accent-soft:rgba(231,154,46,0.14);--jade:#0E7F63;
    --shadow:0 1px 2px rgba(20,26,50,.05),0 12px 32px -12px rgba(20,26,50,.18);
    --c-node-a:rgba(231,154,46,.85);--c-node-b:rgba(35,120,150,.55);--c-link:rgba(20,26,50,.14);
  }
  :root[data-theme="dark"]{
    --bg:#0E1428;--bg-elev:#161D34;--hero-1:#0B1022;--hero-2:#141C38;--ink:#E9ECF7;--ink-soft:#AEB6D0;--ink-mute:#7C86A6;
    --line:rgba(233,236,247,0.11);--line-2:rgba(233,236,247,0.06);--accent:#F5B44E;--accent-fill:#F5B44E;--accent-soft:rgba(245,180,78,0.13);--jade:#3FC7A6;
    --shadow:0 1px 2px rgba(0,0,0,.3),0 18px 40px -16px rgba(0,0,0,.55);
    --c-node-a:rgba(245,180,78,.9);--c-node-b:rgba(63,199,166,.5);--c-link:rgba(233,236,247,.12);
  }
  html{scrollbar-gutter:stable}
  *{box-sizing:border-box}
  body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--font-sans);
    line-height:1.65;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
  html[lang="zh"] body{line-height:1.75}
  .wrap{max-width:1080px;margin:0 auto;padding:0 24px}
  .section{padding:clamp(3.8rem,8.5vw,6.6rem) 0}
  a{color:inherit;text-decoration:none}
  h1,h2,h3{margin:0;text-wrap:balance;letter-spacing:-.02em;line-height:1.12}
  html[lang="zh"] h1,html[lang="zh"] h2,html[lang="zh"] h3{letter-spacing:-.01em;line-height:1.2}
  p{margin:0}
  .eyebrow{font-family:var(--font-mono);font-size:.74rem;letter-spacing:.22em;text-transform:uppercase;color:var(--accent);font-weight:600}
  .mute{color:var(--ink-mute)} .soft{color:var(--ink-soft)}

  header{position:sticky;top:0;z-index:20;backdrop-filter:saturate(1.4) blur(12px);
    background:color-mix(in srgb,var(--bg) 82%,transparent);border-bottom:1px solid var(--line-2)}
  .nav{display:flex;align-items:center;justify-content:space-between;height:64px;gap:1rem}
  .brand{display:flex;align-items:center;gap:.6rem;font-weight:800;font-size:1.2rem;letter-spacing:-.03em}
  .brand .mark{width:26px;height:26px;display:grid;place-items:center;filter:drop-shadow(0 3px 8px color-mix(in srgb,var(--accent-fill) 42%,transparent))}
  .nav-links{display:flex;align-items:center;gap:1.8rem}
  .nav-links a.lk{font-size:.95rem;color:var(--ink-soft);transition:color .18s;white-space:nowrap}
  .nav-links a.lk:hover{color:var(--ink)}
  .btn{display:inline-flex;align-items:center;gap:.5rem;border-radius:10px;font-weight:600;font-size:.95rem;
    padding:.6rem 1.15rem;cursor:pointer;border:1px solid transparent;transition:.18s}
  .btn-ghost{color:var(--ink-soft);border-color:var(--line)}
  .btn-ghost:hover{color:var(--ink);border-color:var(--ink-mute)}
  .btn-primary{background:var(--accent-fill);color:#1a1204;border-color:var(--accent-fill);font-weight:700}
  .btn-primary:hover{filter:brightness(1.06);transform:translateY(-1px);box-shadow:0 10px 24px -10px var(--accent-fill)}
  .langsel{position:relative}
  .globe{border:1px solid var(--line);background:transparent;border-radius:9px;padding:.28rem .5rem;cursor:pointer;font-size:1rem;line-height:1;color:var(--ink-soft)}
  .globe:hover{border-color:var(--ink-mute)}
  .langmenu{position:absolute;right:0;top:calc(100% + .4rem);background:var(--bg-elev);border:1px solid var(--line);border-radius:10px;min-width:118px;padding:.3rem;display:none;box-shadow:var(--shadow);z-index:30}
  .langmenu.show{display:block}
  .langmenu a{display:block;padding:.5rem .6rem;border-radius:7px;color:var(--ink-soft);text-decoration:none;font-size:.9rem}
  .langmenu a:hover{background:var(--accent-soft);color:var(--accent)}
  .langmenu a.on{color:var(--accent);font-weight:600}
  @media (max-width:820px){.nav-links a.lk{display:none}.nav-links{gap:.6rem}.nav-links .btn{padding:.5rem .7rem;font-size:.88rem;white-space:nowrap}}

  .hero{position:relative;overflow:hidden;background:radial-gradient(120% 90% at 78% 8%,var(--hero-2),var(--hero-1) 60%)}
  .hero canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
  .hero .wrap{position:relative;z-index:2;padding-top:clamp(3.5rem,7vw,5.5rem);padding-bottom:clamp(3.5rem,7vw,5.5rem)}
  .hero-inner{max-width:680px}
  .status{display:inline-flex;align-items:center;gap:.5rem;font-family:var(--font-mono);font-size:.78rem;color:var(--ink-soft);
    border:1px solid var(--line);border-radius:999px;padding:.35rem .8rem;background:color-mix(in srgb,var(--bg-elev) 60%,transparent)}
  .dot{width:7px;height:7px;border-radius:50%;background:var(--jade);box-shadow:0 0 0 0 color-mix(in srgb,var(--jade) 70%,transparent);animation:pulse 2.4s infinite}
  @keyframes pulse{0%{box-shadow:0 0 0 0 color-mix(in srgb,var(--jade) 60%,transparent)}70%{box-shadow:0 0 0 7px transparent}100%{box-shadow:0 0 0 0 transparent}}
  h1.title{font-size:clamp(2.5rem,6vw,4.3rem);font-weight:800;margin:1.3rem 0 0;letter-spacing:-.035em}
  html[lang="zh"] h1.title{letter-spacing:-.01em}
  h1.title .hl{color:var(--accent);white-space:nowrap}
  .lede{font-size:clamp(1.05rem,2.2vw,1.28rem);color:var(--ink-soft);margin-top:1.25rem;max-width:38em}
  .cta-row{display:flex;gap:.85rem;margin-top:2rem;flex-wrap:wrap}
  .btn-lg{padding:.8rem 1.5rem;font-size:1.02rem;border-radius:12px}

  .stats{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--bg-elev)}
  .stat-grid{display:grid;grid-template-columns:repeat(4,1fr)}
  .stat{padding:1.6rem 1.4rem;border-left:1px solid var(--line-2)}
  .stat:first-child{border-left:none}
  .stat .num{font-family:var(--font-mono);font-size:1.7rem;font-weight:600;letter-spacing:-.02em;color:var(--ink);font-variant-numeric:tabular-nums}
  .stat .lab{font-size:.86rem;color:var(--ink-mute);margin-top:.25rem}
  @media (max-width:760px){.stat-grid{grid-template-columns:repeat(2,1fr)}.stat:nth-child(3){border-left:none}}

  .head{max-width:42rem;margin-bottom:2.6rem}
  .head h2{font-size:clamp(1.7rem,3.6vw,2.45rem);font-weight:800;margin-top:.7rem}
  .head p{color:var(--ink-soft);margin-top:.8rem;font-size:1.05rem}

  .steps{display:grid;grid-template-columns:repeat(3,1fr);gap:1.1rem}
  .step{position:relative;background:var(--bg-elev);border:1px solid var(--line);border-radius:16px;padding:1.7rem 1.5rem}
  .step .n{font-family:var(--font-mono);font-size:.85rem;font-weight:600;color:var(--accent);letter-spacing:.1em}
  .step h3{font-size:1.18rem;font-weight:700;margin:.9rem 0 .5rem}
  .step p{color:var(--ink-soft);font-size:.98rem}
  .step .arrow{position:absolute;right:-.9rem;top:50%;transform:translateY(-50%);color:var(--line);z-index:3;font-size:1.1rem}
  @media (max-width:820px){.steps{grid-template-columns:1fr}.step .arrow{display:none}}

  .grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1.1rem}
  @media (max-width:820px){.grid{grid-template-columns:1fr}}
  .card{background:var(--bg-elev);border:1px solid var(--line);border-radius:16px;padding:1.6rem 1.5rem;transition:border-color .2s,transform .2s}
  .card:hover{border-color:color-mix(in srgb,var(--accent-fill) 45%,var(--line));transform:translateY(-2px)}
  .card .ico{width:38px;height:38px;border-radius:10px;display:grid;place-items:center;background:var(--accent-soft);color:var(--accent);margin-bottom:1rem;font-size:1.1rem}
  .card h3{font-size:1.08rem;font-weight:700;margin-bottom:.45rem}
  .card p{color:var(--ink-soft);font-size:.96rem}

  .connect{background:var(--bg-elev);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
  .term{background:linear-gradient(180deg,color-mix(in srgb,var(--ink) 4%,var(--bg)),var(--bg));border:1px solid var(--line);border-radius:14px;overflow:hidden;box-shadow:var(--shadow)}
  .term-bar{display:flex;align-items:center;gap:.5rem;padding:.7rem 1rem;border-bottom:1px solid var(--line-2);background:color-mix(in srgb,var(--ink) 5%,transparent)}
  .term-bar i{width:11px;height:11px;border-radius:50%;background:var(--line);display:inline-block}
  .term-bar i:nth-child(1){background:#e4655f}.term-bar i:nth-child(2){background:#e7b34e}.term-bar i:nth-child(3){background:#5bbd7b}
  .term-bar span{margin-left:.5rem;font-family:var(--font-mono);font-size:.76rem;color:var(--ink-mute)}
  .term pre{margin:0;padding:1.3rem 1.4rem;overflow-x:auto;font-family:var(--font-mono);font-size:.9rem;line-height:1.85;color:var(--ink-soft)}
  .term .c{color:var(--ink-mute)}.term .k{color:var(--accent);font-weight:600}.term .s{color:var(--jade)}.term .w{color:var(--ink);font-weight:600}
  .connect-grid{display:grid;grid-template-columns:1fr 1.15fr;gap:2.4rem;align-items:center}
  @media (max-width:860px){.connect-grid{grid-template-columns:1fr;gap:1.8rem}}

  .price{display:grid;grid-template-columns:1.1fr .9fr;gap:2rem;align-items:center;background:var(--bg-elev);border:1px solid var(--line);border-radius:20px;padding:clamp(1.8rem,4vw,2.8rem);box-shadow:var(--shadow)}
  @media (max-width:820px){.price{grid-template-columns:1fr}}
  .price h2{font-size:clamp(1.6rem,3.4vw,2.2rem);font-weight:800}
  .price .big{font-family:var(--font-mono);font-size:2.6rem;font-weight:600;color:var(--accent);letter-spacing:-.02em;font-variant-numeric:tabular-nums}
  .price ul{margin:1.1rem 0 0;padding:0;list-style:none;display:grid;gap:.6rem}
  .price li{display:flex;gap:.6rem;color:var(--ink-soft);font-size:1rem}
  .price li b{color:var(--ink);font-weight:600}
  .check{color:var(--jade);flex:none;margin-top:.15rem}

  .faq{display:grid;gap:.7rem}
  details{background:var(--bg-elev);border:1px solid var(--line);border-radius:13px;padding:.3rem 1.2rem}
  summary{cursor:pointer;list-style:none;padding:1rem 0;font-weight:600;font-size:1.03rem;display:flex;justify-content:space-between;align-items:center;gap:1rem}
  summary::-webkit-details-marker{display:none}
  summary::after{content:"+";font-family:var(--font-mono);color:var(--accent);font-size:1.3rem;flex:none;transition:transform .2s}
  details[open] summary::after{transform:rotate(45deg)}
  details p{color:var(--ink-soft);padding:0 0 1.1rem;font-size:.98rem}

  .footcta{text-align:center}
  .footcta h2{font-size:clamp(1.9rem,4vw,2.8rem);font-weight:800}
  .footcta p{color:var(--ink-soft);margin:1rem auto 0;max-width:34em;font-size:1.08rem}
  footer{border-top:1px solid var(--line);padding:2.4rem 0;color:var(--ink-mute);font-size:.9rem}
  .foot-row{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap}
  .foot-row .mono{font-family:var(--font-mono);font-size:.8rem}
  .foot-links{display:flex;flex-wrap:wrap;gap:1.2rem}
  .foot-links a{color:var(--ink-soft);font-size:.88rem}.foot-links a:hover{color:var(--accent)}

  .reveal{opacity:0;transform:translateY(14px);animation:rise .7s cubic-bezier(.2,.7,.2,1) forwards}
  .reveal.d1{animation-delay:.08s}.reveal.d2{animation-delay:.16s}.reveal.d3{animation-delay:.24s}
  @keyframes rise{to{opacity:1;transform:none}}
  @media (prefers-reduced-motion:reduce){.reveal{animation:none;opacity:1;transform:none}.dot{animation:none}.btn-primary:hover{transform:none}.card:hover{transform:none}}
  :focus-visible{outline:2px solid var(--accent-fill);outline-offset:3px;border-radius:4px}
/* mobile nav + a11y baseline */
.skip-link{position:absolute;left:0;top:0;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);white-space:nowrap;background:var(--bg-elev);color:var(--ink);padding:.6rem 1rem;border-radius:0 0 10px 0;z-index:100;font-size:.95rem}
.skip-link:focus{width:auto;height:auto;overflow:visible;clip:auto;clip-path:none}
a:focus-visible,button:focus-visible{outline:2px solid var(--accent-fill);outline-offset:2px}
.nav-burger{display:none;background:none;border:1px solid var(--line);border-radius:8px;padding:.25rem .55rem;font-size:1.15rem;line-height:1.4;color:var(--ink);cursor:pointer}
@media (max-width:820px){
  .nav-burger{display:inline-flex}
  .nav{height:auto;min-height:64px;flex-wrap:wrap;padding:.5rem 0}
  .nav.open .nav-links{flex:1 1 100%;flex-wrap:wrap;justify-content:flex-end}
  .nav.open .nav-links a.lk{display:block;order:10;flex:1 1 100%;padding:.55rem 0;margin:0;border-top:1px solid var(--line-2);font-size:1rem}
}