@font-face{font-family:"Noto Serif SC";font-style:normal;font-weight:600;font-display:swap;src:url("/fonts/noto-serif-sc-600.woff2") format("woff2")}
@font-face{font-family:"Noto Serif SC";font-style:normal;font-weight:700;font-display:swap;src:url("/fonts/noto-serif-sc-700.woff2") format("woff2")}
@font-face{font-family:"Noto Serif SC";font-style:normal;font-weight:900;font-display:swap;src:url("/fonts/noto-serif-sc-900.woff2") format("woff2")}
:root{
  --bg:#0a0908;
  --bg-2:#100e0c;
  --paper:#f6eedd;
  --paper-ink:#1c1712;
  --amber:#ffb800;
  --amber-deep:#ff8c00;
  --amber-soft:rgba(255,184,0,.14);
  --ink:rgba(255,255,255,.92);
  --ink-2:rgba(255,255,255,.6);
  --ink-3:rgba(255,255,255,.38);
  --hair:rgba(255,255,255,.09);
  --grey-node:#3a382f;
  --serif:"Noto Serif SC","Songti SC","STSong",serif;
  --sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Segoe UI",sans-serif;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  background:var(--bg);
  color:var(--ink);
  font-family:var(--sans);
  font-size:16px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
::selection{background:var(--amber);color:#1a1200}
a{color:inherit;text-decoration:none}
img,svg,canvas{display:block}

/* ---------- grain overlay ---------- */
body::after{
  content:"";position:fixed;inset:0;pointer-events:none;z-index:120;opacity:.05;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- header ---------- */
header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  transition:background .5s ease,border-color .5s ease;
  border-bottom:1px solid transparent;
}
header.scrolled{
  background:rgba(10,9,8,.72);
  -webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
  border-bottom-color:var(--hair);
}
.header-inner{
  max-width:1200px;margin:0 auto;padding:0 28px;height:68px;
  display:flex;align-items:center;gap:32px;
}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:17px;letter-spacing:.02em}
.bmark{width:26px;height:26px;flex:none}
.brand-co{
  font-size:11px;font-weight:400;color:var(--ink-3);letter-spacing:.06em;
  border-left:1px solid var(--hair);padding-left:12px;margin-left:2px;
}
nav{display:flex;gap:26px;margin-left:auto;font-size:13.5px;color:var(--ink-2)}
nav a{position:relative;padding:4px 0;transition:color .3s}
nav a:hover{color:var(--ink)}
nav a::after{
  content:"";position:absolute;left:0;bottom:0;height:1px;width:0;
  background:var(--amber);transition:width .35s cubic-bezier(.4,0,.2,1);
}
nav a:hover::after{width:100%}
.login-link{
  flex:none;font-size:13.5px;font-weight:600;color:var(--ink);
  padding:8px 20px;border-radius:999px;
  border:1px solid rgba(255,184,0,.45);
  background:linear-gradient(180deg,rgba(255,184,0,.12),rgba(255,140,0,.06));
  transition:transform .3s cubic-bezier(.34,1.56,.64,1),box-shadow .3s,background .3s;
}
.login-link:hover{transform:scale(1.07);box-shadow:0 0 24px rgba(255,184,0,.25);background:linear-gradient(180deg,rgba(255,184,0,.2),rgba(255,140,0,.1))}
.login-link:active{transform:scale(.96)}

/* ---------- hero ---------- */
.hero{position:relative;min-height:100vh;display:flex;align-items:center;overflow:hidden}
#tree-canvas{position:absolute;inset:0;width:100%;height:100%}
.hero-veil{
  position:absolute;inset:0;pointer-events:none;
  background:linear-gradient(100deg,rgba(10,9,8,.94) 0%,rgba(10,9,8,.82) 34%,rgba(10,9,8,.25) 62%,rgba(10,9,8,.05) 100%);
}
.hero-veil::after{
  content:"";position:absolute;inset:0;
  background:radial-gradient(120% 90% at 50% 110%,rgba(10,9,8,.9) 0%,transparent 55%);
}
.hero-inner{position:relative;z-index:2;max-width:1200px;margin:0 auto;padding:140px 28px 90px;width:100%}
.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  font-size:12.5px;letter-spacing:.28em;color:var(--amber);
  text-transform:uppercase;font-weight:600;margin-bottom:28px;
}
.eyebrow i{width:34px;height:1px;background:linear-gradient(90deg,var(--amber),transparent)}
h1{
  font-family:var(--serif);font-weight:900;
  font-size:clamp(34px,5.2vw,64px);line-height:1.22;letter-spacing:.01em;
  max-width:15em;
}
h1 .lit{
  color:transparent;
  background:linear-gradient(115deg,#ffd96a 0%,var(--amber) 45%,var(--amber-deep) 100%);
  -webkit-background-clip:text;background-clip:text;
  text-shadow:0 0 42px rgba(255,160,0,.28);
}
.hero-sub{
  margin-top:26px;max-width:34em;
  font-size:17px;color:var(--ink-2);line-height:1.9;
}
.hero-sub b{color:var(--ink);font-weight:600}
.hero-cta{display:flex;gap:16px;margin-top:44px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;gap:10px;
  padding:14px 32px;border-radius:999px;font-size:15px;font-weight:600;
  transition:transform .35s cubic-bezier(.34,1.56,.64,1),box-shadow .35s,background .35s,border-color .35s;
  cursor:pointer;
}
.btn-primary{
  color:#241600;
  background:linear-gradient(135deg,#ffd051 0%,var(--amber) 45%,var(--amber-deep) 100%);
  box-shadow:0 6px 30px rgba(255,150,0,.28),inset 0 1px 0 rgba(255,255,255,.5);
}
.btn-primary:hover{transform:scale(1.06);box-shadow:0 10px 44px rgba(255,150,0,.42),inset 0 1px 0 rgba(255,255,255,.5)}
.btn-primary:active{transform:scale(.95)}
.btn-ghost{
  color:var(--ink);border:1px solid var(--hair);
  background:rgba(255,255,255,.04);
}
.btn-ghost:hover{transform:scale(1.06);border-color:rgba(255,184,0,.5);background:rgba(255,184,0,.07)}
.btn-ghost:active{transform:scale(.95)}
.hero-hint{
  margin-top:60px;display:flex;align-items:center;gap:12px;
  font-size:12.5px;color:var(--ink-3);letter-spacing:.12em;
}
.scroll-dot{width:5px;height:5px;border-radius:50%;background:var(--amber);animation:hintdrop 2.2s ease-in-out infinite}
@keyframes hintdrop{0%,100%{transform:translateY(0);opacity:1}50%{transform:translateY(7px);opacity:.35}}

/* ---------- shared section ---------- */
section{position:relative;padding:15vh 0}
.wrap{max-width:1200px;margin:0 auto;padding:0 28px}
.sec-head{margin-bottom:72px;max-width:760px}
.sec-tag{
  font-size:12px;letter-spacing:.3em;color:var(--amber);font-weight:600;
  display:flex;align-items:center;gap:12px;margin-bottom:20px;text-transform:uppercase;
}
.sec-tag::before{content:"";width:28px;height:1px;background:var(--amber)}
h2{font-family:var(--serif);font-weight:700;font-size:clamp(26px,3.4vw,42px);line-height:1.35;letter-spacing:.01em}
.sec-desc{margin-top:18px;color:var(--ink-2);font-size:16px;max-width:38em}

/* hairline divider that draws itself */
.rule{height:1px;background:linear-gradient(90deg,transparent,var(--hair) 18%,var(--hair) 82%,transparent);transform:scaleX(0);transform-origin:center;transition:transform 1.4s cubic-bezier(.22,1,.36,1)}
.rule.in{transform:scaleX(1)}

/* scroll reveal */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .8s ease,transform .8s cubic-bezier(.22,1,.36,1);transition-delay:var(--d,0s)}
.reveal.in{opacity:1;transform:translateY(0)}
@media (prefers-reduced-motion:reduce){
  .reveal{opacity:1;transform:none;transition:none}
  .rule{transform:scaleX(1);transition:none}
  html{scroll-behavior:auto}
}

/* ---------- pain points ---------- */
.pains{display:grid;grid-template-columns:repeat(3,1fr);gap:0;border-top:1px solid var(--hair);border-bottom:1px solid var(--hair)}
.pain{padding:44px 36px 48px;border-left:1px solid var(--hair);position:relative}
.pain:first-child{border-left:none}
.pain-no{
  font-family:var(--serif);font-size:15px;color:var(--amber);font-weight:700;
  letter-spacing:.2em;margin-bottom:20px;
}
.pain h3{font-size:19px;font-weight:700;line-height:1.5;margin-bottom:14px}
.pain p{font-size:14.5px;color:var(--ink-2);line-height:1.85}
.pain::before{
  content:"";position:absolute;top:-1px;left:0;height:1px;width:0;
  background:linear-gradient(90deg,var(--amber),transparent);
  transition:width .9s cubic-bezier(.22,1,.36,1);
}
.pain:hover::before{width:100%}

/* ---------- loop (paper band) ---------- */
.band-paper{background:var(--paper);color:var(--paper-ink)}
.band-paper .sec-tag{color:#b07400}
.band-paper .sec-tag::before{background:#b07400}
.band-paper .sec-desc{color:rgba(28,23,18,.66)}
.loop{display:grid;grid-template-columns:repeat(6,1fr);gap:0}
.step{
  position:relative;padding:30px 22px 34px;
  border-left:1px solid rgba(28,23,18,.14);
}
.step:first-child{border-left:none;padding-left:0}
.step-no{
  width:44px;height:44px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  font-family:var(--serif);font-weight:700;font-size:17px;
  border:1.5px solid rgba(28,23,18,.28);color:rgba(28,23,18,.75);
  margin-bottom:20px;background:transparent;
  transition:all .4s ease;
}
.step:hover .step-no{
  border-color:var(--amber-deep);color:#241600;
  background:linear-gradient(135deg,#ffd051,var(--amber-deep));
  box-shadow:0 6px 20px rgba(255,150,0,.35);
}
.step h3{font-size:16.5px;font-weight:700;margin-bottom:10px}
.step p{font-size:13.5px;line-height:1.8;color:rgba(28,23,18,.62)}
.step .arr{
  position:absolute;top:48px;right:-9px;z-index:2;color:#c98a00;font-size:14px;
}
.loop-foot{
  margin-top:56px;padding-top:28px;border-top:1px solid rgba(28,23,18,.14);
  font-size:14px;color:rgba(28,23,18,.6);display:flex;gap:10px;align-items:baseline;flex-wrap:wrap;
}
.loop-foot b{color:var(--paper-ink)}

/* ---------- states & rules ---------- */
.states-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:80px;align-items:start}
.state-list{display:flex;flex-direction:column}
.state{
  display:flex;gap:22px;align-items:flex-start;
  padding:26px 0;border-bottom:1px solid var(--hair);
}
.state:last-child{border-bottom:none}
.node-demo{width:56px;height:56px;flex:none;display:flex;align-items:center;justify-content:center}
.nd{width:22px;height:22px;border-radius:50%;position:relative}
.nd-locked{background:var(--grey-node);box-shadow:inset 0 1px 2px rgba(0,0,0,.6)}
.nd-open{
  background:transparent;border:2px solid var(--amber);
  box-shadow:0 0 10px rgba(255,184,0,.3),inset 0 0 6px rgba(255,184,0,.15);
}
.nd-pending{
  background:radial-gradient(circle at 35% 30%,#ffe9ad,var(--amber) 55%,var(--amber-deep));
  animation:pendpulse 1.6s ease-in-out infinite;
}
@keyframes pendpulse{
  0%,100%{box-shadow:0 0 8px 2px rgba(255,184,0,.35)}
  50%{box-shadow:0 0 22px 8px rgba(255,184,0,.65)}
}
.nd-lit{
  background:radial-gradient(circle at 35% 30%,#fff3cf,#ffcf4d 40%,var(--amber) 70%,var(--amber-deep));
  box-shadow:0 0 14px 4px rgba(255,170,0,.55),0 0 40px 10px rgba(255,150,0,.18);
}
.state h3{font-size:16.5px;font-weight:700;margin-bottom:6px}
.state h3 span{font-size:12px;color:var(--ink-3);font-weight:400;margin-left:10px;letter-spacing:.08em}
.state p{font-size:14px;color:var(--ink-2);line-height:1.8}
.rules{display:flex;flex-direction:column;border-top:1px solid var(--hair)}
.rule-item{display:flex;gap:18px;padding:22px 0;border-bottom:1px solid var(--hair);font-size:14.5px;color:var(--ink-2);line-height:1.8}
.rule-item b{color:var(--ink);font-weight:600}
.rule-item .dot{
  flex:none;width:7px;height:7px;border-radius:50%;margin-top:11px;
  background:var(--amber);box-shadow:0 0 8px rgba(255,184,0,.6);
}

/* ---------- roles ---------- */
.roles{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--hair);border-radius:20px;overflow:hidden}
.role{padding:52px 48px}
.role-teacher{border-right:1px solid var(--hair);background:linear-gradient(160deg,rgba(255,184,0,.06),transparent 55%)}
.role-tag{
  display:inline-block;font-size:12px;letter-spacing:.22em;font-weight:600;
  color:var(--amber);margin-bottom:18px;
}
.role-student .role-tag{color:var(--ink-2)}
.role h3{font-family:var(--serif);font-size:24px;font-weight:700;margin-bottom:8px}
.role .who{font-size:13px;color:var(--ink-3);margin-bottom:26px}
.role ul{list-style:none;display:flex;flex-direction:column;gap:16px}
.role li{display:flex;gap:14px;font-size:14.5px;color:var(--ink-2);line-height:1.8}
.role li svg{flex:none;margin-top:5px}
.role li b{color:var(--ink);font-weight:600}

/* ---------- numbers ---------- */
.numbers{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--hair);border-bottom:1px solid var(--hair)}
.num{padding:44px 32px;border-left:1px solid var(--hair)}
.num:first-child{border-left:none}
.num-v{
  font-family:var(--serif);font-weight:900;
  font-size:clamp(38px,4.4vw,56px);line-height:1;
  background:linear-gradient(135deg,#ffe09a,var(--amber) 60%,var(--amber-deep));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.num-v small{font-size:.45em;font-weight:700;letter-spacing:.05em;margin-left:4px}
.num-l{margin-top:14px;font-size:13.5px;color:var(--ink-2);line-height:1.7}

/* ---------- not-us strip ---------- */
.notus{
  margin-top:14vh;border:1px solid var(--hair);border-radius:20px;
  padding:48px 52px;display:flex;gap:48px;align-items:center;flex-wrap:wrap;
  background:linear-gradient(120deg,rgba(255,184,0,.05),transparent 60%);
}
.notus-l{flex:1 1 320px}
.notus-l h3{font-family:var(--serif);font-size:22px;font-weight:700;line-height:1.5}
.notus-l p{margin-top:10px;font-size:14px;color:var(--ink-2)}
.notus-r{flex:1 1 320px;display:flex;flex-wrap:wrap;gap:12px}
.chip{
  font-size:13.5px;padding:9px 18px;border-radius:999px;
  border:1px solid var(--hair);color:var(--ink-2);background:rgba(255,255,255,.03);
}
.chip.no{color:var(--ink-3);text-decoration:line-through;text-decoration-color:rgba(255,120,80,.7);text-decoration-thickness:1.5px}
.chip.yes{border-color:rgba(255,184,0,.5);color:var(--amber);background:var(--amber-soft)}

/* ---------- free ---------- */
.free-banner{
  display:flex;gap:64px;align-items:center;flex-wrap:wrap;
  border:1px solid rgba(255,184,0,.4);border-radius:24px;
  padding:64px 60px;
  background:
    radial-gradient(60% 120% at 12% 50%,rgba(255,160,20,.12),transparent 70%),
    linear-gradient(165deg,rgba(255,184,0,.06),transparent 55%),var(--bg-2);
}
.free-zero{
  flex:none;font-family:var(--serif);font-weight:900;line-height:1;
  font-size:clamp(90px,12vw,160px);
  background:linear-gradient(150deg,#ffe9ad 5%,var(--amber) 55%,var(--amber-deep) 95%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
  filter:drop-shadow(0 0 34px rgba(255,160,0,.22));
}
.free-text{flex:1 1 380px}
.free-text h2{margin-bottom:16px}
.free-text p{color:var(--ink-2);max-width:36em}
.free-text .hero-cta{margin-top:32px}
.free-points{display:grid;grid-template-columns:repeat(3,1fr);gap:0;margin-top:56px;border-top:1px solid var(--hair);border-bottom:1px solid var(--hair)}
.free-point{padding:32px 30px;border-left:1px solid var(--hair);font-size:14px;color:var(--ink-2);line-height:1.8}
.free-point:first-child{border-left:none}
.free-point b{display:block;color:var(--ink);font-size:15.5px;margin-bottom:8px}

/* ---------- final cta ---------- */
.final{text-align:center;padding:20vh 0}
.final h2{max-width:16em;margin:0 auto}
.final p{margin:22px auto 0;color:var(--ink-2);max-width:34em}
.final .hero-cta{justify-content:center}

/* ---------- footer ---------- */
footer{border-top:1px solid var(--hair);padding:56px 0 48px}
.foot-inner{max-width:1200px;margin:0 auto;padding:0 28px;display:flex;flex-wrap:wrap;gap:28px;align-items:flex-end;justify-content:space-between}
.foot-brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:15px}
.foot-co{margin-top:10px;font-size:13px;color:var(--ink-3);line-height:1.9}
.foot-links{display:flex;gap:24px;font-size:13px;color:var(--ink-3)}
.foot-links a:hover{color:var(--ink-2)}
.foot-copy{font-size:12.5px;color:var(--ink-3);text-align:right;line-height:1.9}
/* 页脚互链：首页与营销静态页共用（/templates /blog /faq /about） */
.foot-links{display:flex;flex-wrap:wrap;gap:8px 22px;font-size:13px}
.foot-links a{color:var(--ink-3);transition:color .3s}
.foot-links a:hover{color:var(--amber)}

/* ---------- responsive ---------- */
@media (max-width:980px){
  nav{display:none}
  .brand-co{display:none}
  .pains{grid-template-columns:1fr}
  .pain{border-left:none;border-top:1px solid var(--hair)}
  .pain:first-child{border-top:none}
  .loop{grid-template-columns:repeat(2,1fr)}
  .step{border-left:none;border-top:1px solid rgba(28,23,18,.14);padding-left:0}
  .step .arr{display:none}
  .states-grid{grid-template-columns:1fr;gap:48px}
  .roles{grid-template-columns:1fr}
  .role-teacher{border-right:none;border-bottom:1px solid var(--hair)}
  .numbers{grid-template-columns:repeat(2,1fr)}
  .num{border-left:none;border-top:1px solid var(--hair)}
  .num:nth-child(odd){border-left:none}
  .num:nth-child(-n+2){border-top:none}
  .free-banner{padding:44px 32px;gap:36px}
  .free-points{grid-template-columns:1fr}
  .free-point{border-left:none;border-top:1px solid var(--hair)}
  .free-point:first-child{border-top:none}
  .role{padding:38px 30px}
  .notus{padding:36px 30px}
}