/* Generated from web/ui/styles — edit modules, not public/learning.css. */

/* module: 00-foundations.css */
:root{
  --bg:#060b13;
  --bg-soft:#09101a;
  --surface:#0c1421;
  --surface-1:#0c1421;
  --surface-2:#101a2a;
  --surface-3:#172235;
  --line:rgba(181,205,235,.15);
  --line-strong:rgba(181,205,235,.27);
  --text:#f8fafc;
  --text-soft:#cbd5e1;
  --muted:#94a3b8;
  --yellow:#ffd84a;
  --yellow-soft:#ffec9a;
  --cyan:#55bfff;
  --mint:#61e6b5;
  --pink:#ff7f9f;
  --violet:#a995ff;
  --container:1304px;
  --control-height:48px;
  --radius-sm:14px;
  --radius:22px;
  --radius-lg:28px;
  --shadow:0 28px 90px rgba(0,0,0,.34);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;color-scheme:dark}
body{
  margin:0;
  min-width:320px;
  background:
    radial-gradient(circle at 12% 0%,rgba(86,216,255,.065),transparent 30rem),
    radial-gradient(circle at 88% 16%,rgba(255,216,74,.055),transparent 28rem),
    var(--bg);
  color:var(--text);
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(255,255,255,.018) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.018) 1px,transparent 1px);
  background-size:44px 44px;
  mask-image:linear-gradient(to bottom,black,transparent 75%);
}
a{color:inherit}
button,input,select{font:inherit}
button{color:inherit}
img,canvas{max-width:100%}
.wrap{width:min(var(--container),calc(100% - 48px));margin-inline:auto}
main{overflow:hidden}
.site-header{
  position:sticky;
  top:0;
  z-index:50;
  background:rgba(6,11,19,.82);
  border-bottom:1px solid var(--line);
  backdrop-filter:blur(18px) saturate(140%);
}
.nav{min-height:72px;display:flex;align-items:center;gap:30px}
.brand{
  display:inline-flex;
  align-items:center;
  gap:9px;
  flex:none;
  text-decoration:none;
  font-size:15px;
  font-weight:850;
  letter-spacing:-.01em;
}
.brand-mark{
  width:38px;
  height:38px;
  display:grid;
  place-items:center;
  border:1px solid rgba(255,216,74,.38);
  border-radius:10px;
  background:rgba(255,216,74,.09);
  color:var(--yellow);
  font-family:Georgia,serif;
  font-size:20px;
  line-height:1;
  box-shadow:inset 0 0 18px rgba(255,216,74,.05);
}
.brand-name{color:var(--text)}
.brand-daily{
  padding:3px 7px;
  border:1px solid var(--line);
  border-radius:999px;
  color:var(--muted);
  font-size:9px;
  font-weight:900;
  letter-spacing:.14em;
  text-transform:uppercase;
}
.nav-links{display:flex;align-items:center;gap:4px;margin-left:auto}
.nav-links a{
  padding:9px 13px;
  border-radius:10px;
  color:var(--muted);
  text-decoration:none;
  font-size:13px;
  font-weight:750;
}
.nav-links a:hover{background:rgba(255,255,255,.045);color:var(--text)}
.nav-cta{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:44px;
  padding:0 16px;
  border:1px solid rgba(255,216,74,.32);
  border-radius:12px;
  background:rgba(255,216,74,.08);
  color:var(--yellow-soft);
  text-decoration:none;
  font-size:12px;
  font-weight:850;
  white-space:nowrap;
}
.nav-cta:hover{background:rgba(255,216,74,.14);border-color:rgba(255,216,74,.52)}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{
  outline:3px solid var(--yellow);
  outline-offset:3px;
}
.eyebrow,.meta,.section-kicker{
  color:var(--yellow);
  font-size:12px;
  font-weight:900;
  letter-spacing:.13em;
  text-transform:uppercase;
}
.hero-badge{
  display:inline-flex;
  align-items:center;
  gap:9px;
  width:max-content;
  max-width:100%;
  padding:7px 11px;
  border:1px solid var(--line);
  border-radius:999px;
  background:rgba(255,255,255,.025);
  color:var(--text-soft);
  font-size:12px;
  font-weight:800;
  letter-spacing:.08em;
  text-transform:uppercase;
}
.hero-badge>span{
  width:7px;
  height:7px;
  border-radius:50%;
  background:var(--mint);
  box-shadow:0 0 16px var(--mint);
}
.hero-actions{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin-top:28px}
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  min-height:54px;
  padding:0 20px;
  border:1px solid var(--line-strong);
  border-radius:14px;
  background:var(--surface-2);
  color:var(--text);
  text-decoration:none;
  font-weight:850;
  line-height:1.2;
  cursor:pointer;
  transition:transform .18s ease,border-color .18s ease,background .18s ease,box-shadow .18s ease;
}
.btn.primary{
  border-color:var(--yellow);
  background:var(--yellow);
  color:#11151d;
  box-shadow:0 12px 32px rgba(255,216,74,.14);
}
.btn.ghost{background:rgba(255,255,255,.03)}
.btn:hover{transform:translateY(-2px);border-color:rgba(255,255,255,.35)}
.btn.primary:hover{border-color:var(--yellow-soft);background:var(--yellow-soft);box-shadow:0 16px 36px rgba(255,216,74,.2)}
.text-link{
  display:inline-flex;
  align-items:center;
  gap:8px;
  color:var(--text-soft);
  text-decoration:none;
  font-weight:800;
}
.text-link:hover{color:var(--yellow)}
.section{padding:92px 0}
.alt{
  background:linear-gradient(180deg,rgba(14,19,32,.72),rgba(10,13,21,.72));
  border-block:1px solid var(--line);
}
.section-head{
  display:flex;
  align-items:end;
  justify-content:space-between;
  gap:48px;
  margin-bottom:32px;
}
.section-head h2,.section h2{
  margin:7px 0 0;
  font-size:clamp(32px,4.4vw,54px);
  line-height:1.05;
  letter-spacing:-.045em;
}
.section-head>p{
  max-width:520px;
  margin:0;
  color:var(--muted);
  font-size:16px;
}
.grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:18px}
.card{
  grid-column:span 6;
  padding:26px;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:linear-gradient(145deg,rgba(18,25,39,.95),rgba(12,17,27,.95));
  text-decoration:none;
}
.card.full{grid-column:1/-1}
.card.third{grid-column:span 4}
.card h2,.card h3{margin:7px 0 8px;line-height:1.14}
.card h3{font-size:23px}
.card p{margin:0;color:var(--muted)}
.card[href]{transition:transform .18s ease,border-color .18s ease,background .18s ease}
.card[href]:hover{transform:translateY(-3px);border-color:var(--line-strong);background:var(--surface-2)}
.hero{
  padding:86px 0 64px;
  background:radial-gradient(circle at 78% 10%,rgba(255,216,74,.08),transparent 28rem);
}
.hero h1{
  max-width:900px;
  margin:12px 0 18px;
  font-size:clamp(44px,7vw,82px);
  line-height:.98;
  letter-spacing:-.055em;
}
.hero p{max-width:720px;margin:0;color:var(--muted);font-size:clamp(17px,2vw,21px)}
.accent{color:var(--yellow)}
.narrow{max-width:790px}
.tiny{color:var(--muted);font-size:12px}
.feedback{min-height:24px;margin-top:12px;font-weight:800}
.lead-form{display:grid;gap:14px}
.lead-form label{display:grid;gap:6px}
.lead-form label>span{color:var(--text-soft);font-size:12px;font-weight:800}
.lead-form input,.lead-form select{
  width:100%;
  min-height:50px;
  padding:0 14px;
  border:1px solid var(--line-strong);
  border-radius:12px;
  background:var(--bg-soft);
  color:var(--text);
}
.signup-card{max-width:820px;margin:24px auto}
.price{margin:18px 0;color:var(--yellow);font-size:22px;font-weight:900}
.aha-list{display:grid;gap:12px;margin:30px 0}
.aha-list>div{padding:18px 20px;border:1px solid var(--line);border-radius:var(--radius-sm);background:var(--surface)}
.aha-list b,.aha-list span{display:block}
.aha-list span{margin-top:4px;color:var(--muted)}

.ui-panel{
  border:1px solid var(--line);
  background:linear-gradient(145deg,rgba(16,26,42,.98),rgba(7,12,21,.98));
  box-shadow:var(--shadow),inset 0 1px 0 rgba(255,255,255,.045);
}

/* module: 10-home.css */
/* Home */
.home-hero{
  position:relative;
  padding:82px 0 54px;
  background:
    radial-gradient(circle at 72% 30%,rgba(85,191,255,.12),transparent 28rem),
    radial-gradient(circle at 86% 72%,rgba(255,216,74,.075),transparent 24rem);
}
.home-hero::after{
  content:"";
  position:absolute;
  width:340px;
  height:340px;
  right:-180px;
  top:30px;
  border:1px solid rgba(255,255,255,.06);
  border-radius:50%;
  box-shadow:0 0 0 70px rgba(255,255,255,.016),0 0 0 140px rgba(255,255,255,.012);
  pointer-events:none;
}
.hero-grid{display:grid;grid-template-columns:minmax(0,.82fr) minmax(560px,1.18fr);align-items:center;gap:54px}
.hero-copy{min-width:0}
.hero-copy h1{
  margin:18px 0 20px;
  font-size:clamp(58px,6.2vw,88px);
  line-height:.92;
  letter-spacing:-.065em;
}
.hero-copy h1 span{color:var(--yellow)}
.hero-lede{max-width:610px;margin:0;color:var(--text-soft);font-size:clamp(17px,1.55vw,20px);line-height:1.58}
.hero-facts{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:12px;
  margin:34px 0 0;
  padding:24px 0 0;
  border-top:1px solid var(--line);
  list-style:none;
}
.hero-facts li{display:grid;grid-template-columns:44px minmax(0,1fr);align-items:center;gap:10px;min-width:0}
.fact-icon{width:44px;height:44px;display:grid;place-items:center;border:1px solid var(--line);border-radius:50%;background:rgba(255,255,255,.025);color:var(--cyan)}
.hero-facts li:first-child .fact-icon{border-color:rgba(97,230,181,.24);color:var(--mint)}
.hero-facts li:last-child .fact-icon{border-color:rgba(255,216,74,.22);color:var(--yellow)}
.fact-icon svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.fact-copy{display:grid;gap:1px;min-width:0}
.hero-facts strong{font-size:19px;color:var(--text)}
.hero-facts .fact-copy>span{color:var(--muted);font-size:12px;line-height:1.35}
.hero-lab{
  position:relative;
  min-width:0;
  margin:0;
  padding:22px;
  overflow:hidden;
  border:1px solid rgba(85,191,255,.3);
  border-radius:24px;
  background:linear-gradient(145deg,rgba(15,27,44,.99),rgba(7,12,21,.99));
  box-shadow:var(--shadow),inset 0 1px 0 rgba(255,255,255,.05);
}
.hero-lab::before{
  content:"";
  position:absolute;
  width:180px;
  height:180px;
  right:-50px;
  top:-70px;
  border-radius:50%;
  background:rgba(86,216,255,.12);
  filter:blur(55px);
  pointer-events:none;
}
.stage-top,.interactive-top{display:flex;align-items:start;justify-content:space-between;gap:20px;margin-bottom:14px}
.stage-top h2,.interactive-top h2{margin:5px 0 0;font-size:21px;line-height:1.16;letter-spacing:-.02em}
.live-pill,.status-badge{
  display:inline-flex;
  align-items:center;
  gap:7px;
  width:max-content;
  padding:6px 9px;
  border:1px solid rgba(104,232,179,.24);
  border-radius:999px;
  background:rgba(104,232,179,.07);
  color:var(--mint);
  font-size:11px;
  font-weight:850;
  letter-spacing:.05em;
  text-transform:uppercase;
}
.live-pill i{width:6px;height:6px;border-radius:50%;background:var(--mint);box-shadow:0 0 12px var(--mint)}
.hero-lab canvas,.interactive canvas{
  display:block;
  width:100%;
  height:auto;
  aspect-ratio:16/9;
  border:1px solid var(--line);
  border-radius:16px;
  background:#0a0d15;
}
.control-block{margin-top:16px}
.control-label{margin:0 0 5px;color:var(--text-soft);font-size:14px;font-weight:800}
.control-label::first-letter{color:var(--text)}
.controls{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:16px}
.controls input[type="range"]{
  width:100%;
  min-height:44px;
  margin:0;
  accent-color:var(--yellow);
  cursor:ew-resize;
}
.readout{
  min-width:156px;
  padding:9px 12px;
  border:1px solid var(--line);
  border-radius:11px;
  background:rgba(5,8,14,.78);
  color:var(--text-soft);
  font-size:13px;
  font-variant-numeric:tabular-nums;
  line-height:1.45;
}
.readout strong{color:var(--mint)}
.readout span{display:inline-block;min-width:112px;color:var(--muted);font-size:11px;font-weight:800;letter-spacing:.025em}
.interactive-hint{margin:11px 0 0;color:var(--muted);font-size:13px}
.stage-link{
  display:flex;
  align-items:center;
  justify-content:space-between;
  margin:14px -2px -2px;
  padding:12px 3px 2px;
  border-top:1px solid var(--line);
  color:var(--text-soft);
  text-decoration:none;
  font-size:13px;
  font-weight:800;
}
.stage-link:hover{color:var(--yellow)}
.signal-bar{border-block:1px solid var(--line);background:rgba(14,19,32,.64)}
.signal-inner{
  min-height:58px;
  display:flex;
  align-items:center;
  justify-content:center;
  gap:28px;
  color:var(--text-soft);
  font-size:12px;
  font-weight:900;
  letter-spacing:.12em;
  text-transform:uppercase;
}
.signal-inner i{color:var(--yellow);font-style:normal}
.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
.topic-card{
  min-width:0;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  background:linear-gradient(145deg,var(--surface-2),rgba(10,14,23,.96));
  text-decoration:none;
  transition:transform .2s ease,border-color .2s ease,box-shadow .2s ease;
}
.topic-card:hover{transform:translateY(-5px);border-color:var(--line-strong);box-shadow:0 24px 50px rgba(0,0,0,.2)}
.topic-art{position:relative;height:auto;aspect-ratio:16/9;overflow:hidden;border-bottom:1px solid var(--line);background-color:#0a0e17}
.topic-preview{
  display:block;
  width:100%;
  height:100%;
  background:#0a0e17;
}
.axis-x,.axis-y{position:absolute;z-index:1;background:rgba(203,210,223,.35)}
.axis-x{left:10%;right:8%;height:1px;top:67%}
.axis-y{top:10%;bottom:8%;width:1px;left:28%}
.curve-line{
  position:absolute;
  z-index:2;
  width:82%;
  height:3px;
  left:8%;
  top:56%;
  border-radius:99px;
  background:var(--cyan);
  transform:rotate(-27deg);
  box-shadow:0 0 18px rgba(86,216,255,.35);
}
.hole-dot{
  position:absolute;
  z-index:3;
  width:18px;
  height:18px;
  left:55%;
  top:45%;
  border:4px solid var(--yellow);
  border-radius:50%;
  background:#0a0e17;
  box-shadow:0 0 18px rgba(255,216,74,.35);
}
.derivative-art{background:radial-gradient(circle at 65% 35%,rgba(255,127,159,.11),transparent 45%),#0a0e17}
.curve-arc{
  position:absolute;
  z-index:2;
  width:75%;
  height:155%;
  left:12%;
  top:27%;
  border:4px solid var(--pink);
  border-radius:50%;
  box-shadow:0 0 18px rgba(255,127,159,.24);
}
.tangent-line{
  position:absolute;
  z-index:3;
  width:75%;
  height:3px;
  left:26%;
  top:44%;
  background:var(--yellow);
  transform:rotate(-32deg);
  box-shadow:0 0 18px rgba(255,216,74,.3);
}
.focus-dot{
  position:absolute;
  z-index:4;
  width:16px;
  height:16px;
  left:61%;
  top:40%;
  border-radius:50%;
  background:var(--mint);
  box-shadow:0 0 18px var(--mint);
}
.integral-art{background:radial-gradient(circle at 45% 50%,rgba(104,232,179,.1),transparent 45%),#0a0e17}
.area-fill{
  position:absolute;
  z-index:1;
  left:16%;
  bottom:17%;
  width:62%;
  height:68%;
  clip-path:polygon(0 100%,100% 6%,100% 100%);
  background:linear-gradient(135deg,rgba(104,232,179,.08),rgba(104,232,179,.34));
}
.integral-line{
  position:absolute;
  z-index:3;
  left:14%;
  top:48%;
  width:70%;
  height:4px;
  border-radius:99px;
  background:var(--mint);
  transform:rotate(-31deg);
  box-shadow:0 0 20px rgba(104,232,179,.34);
}
.bound-line{
  position:absolute;
  z-index:4;
  left:78%;
  top:21%;
  width:3px;
  height:64%;
  background:var(--yellow);
}
.topic-copy{padding:24px}
.topic-meta{display:flex;justify-content:space-between;gap:12px;color:var(--muted);font-size:11px;font-weight:900;letter-spacing:.1em;text-transform:uppercase}
.topic-card.limits .topic-meta span:first-child{color:var(--cyan)}
.topic-card.derivatives .topic-meta span:first-child{color:var(--pink)}
.topic-card.integrals .topic-meta span:first-child{color:var(--mint)}
.topic-copy h3{margin:12px 0 8px;font-size:25px;line-height:1.08;letter-spacing:-.025em}
.topic-copy p{margin:0;color:var(--muted);font-size:14px}
.card-action{display:flex;justify-content:space-between;margin-top:22px;color:var(--text-soft);font-size:13px;font-weight:850}
.card-action b{color:var(--yellow)}
.route-grid{display:grid;grid-template-columns:minmax(0,.9fr) minmax(420px,1fr);align-items:center;gap:86px}
.route-copy h2{margin:8px 0 18px;font-size:clamp(38px,5vw,64px);line-height:.99;letter-spacing:-.05em}
.route-copy>p{max-width:570px;margin:0;color:var(--muted);font-size:17px}
.method-steps{display:grid;gap:12px;margin:0;padding:0;list-style:none}
.method-steps li{
  display:grid;
  grid-template-columns:54px 1fr;
  gap:18px;
  align-items:start;
  padding:21px;
  border:1px solid var(--line);
  border-radius:18px;
  background:rgba(18,25,39,.72);
}
.method-steps li>span{color:var(--yellow);font-size:12px;font-weight:900;letter-spacing:.08em}
.method-steps strong{display:block;font-size:18px}
.method-steps p{margin:3px 0 0;color:var(--muted);font-size:14px}
.track-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:18px}
.track-card{
  position:relative;
  min-height:210px;
  display:grid;
  grid-template-columns:48px 1fr auto;
  align-items:start;
  gap:18px;
  padding:26px;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:linear-gradient(145deg,var(--surface-2),var(--surface));
  text-decoration:none;
}
.track-featured{
  grid-row:span 2;
  align-content:end;
  min-height:438px;
  background:
    radial-gradient(circle at 70% 24%,rgba(86,216,255,.16),transparent 15rem),
    linear-gradient(145deg,var(--surface-2),var(--surface));
}
.track-card::after{
  content:"";
  position:absolute;
  right:-44px;
  bottom:-60px;
  width:180px;
  height:180px;
  border:1px solid rgba(255,255,255,.07);
  border-radius:50%;
  box-shadow:0 0 0 36px rgba(255,255,255,.018),0 0 0 72px rgba(255,255,255,.012);
}
.track-card:hover{border-color:var(--line-strong)}
.track-number{color:var(--yellow);font-size:12px;font-weight:900}
.track-card h3{margin:7px 0;font-size:29px;line-height:1.08}
.track-card p{max-width:520px;margin:0;color:var(--muted)}
.track-arrow{z-index:1;color:var(--yellow);font-size:20px}
.pack-section{padding-top:20px}
.pack-banner{
  position:relative;
  display:grid;
  grid-template-columns:180px 1fr auto;
  align-items:center;
  gap:34px;
  min-height:230px;
  padding:34px 38px;
  overflow:hidden;
  border:1px solid rgba(255,216,74,.24);
  border-radius:var(--radius-lg);
  background:
    radial-gradient(circle at 14% 50%,rgba(255,216,74,.14),transparent 16rem),
    linear-gradient(135deg,#151825,#0d111b);
}
.pack-copy h2{margin:6px 0 8px;font-size:clamp(31px,4vw,48px);line-height:1.02}
.pack-copy p{margin:0;color:var(--muted)}
.pack-orbit{position:relative;width:150px;height:150px;margin:auto;border:1px solid rgba(255,216,74,.24);border-radius:50%}
.pack-orbit::before,.pack-orbit::after{content:"";position:absolute;inset:22px;border:1px solid rgba(86,216,255,.2);border-radius:50%}
.pack-orbit::after{inset:46px;background:var(--yellow);box-shadow:0 0 45px rgba(255,216,74,.32)}
.pack-orbit span,.pack-orbit i,.pack-orbit b{position:absolute;width:12px;height:12px;border-radius:50%}
.pack-orbit span{left:12px;top:47%;background:var(--cyan)}
.pack-orbit i{right:27px;top:15px;background:var(--mint)}
.pack-orbit b{right:14px;bottom:27px;background:var(--pink)}

.start-section{
  padding-top:42px;
  border-top:1px solid var(--line);
  background:linear-gradient(180deg,rgba(7,12,21,.18),rgba(12,20,33,.34));
}
.start-section .section-head{padding-top:8px}
.start-section .section-head h2{font-size:clamp(32px,3.6vw,48px)}

/* module: 20-learning-pages.css */
/* Library */
.page-hero{padding:92px 0 76px;border-bottom:1px solid var(--line)}
.page-hero-grid{display:grid;grid-template-columns:minmax(0,1fr) 390px;align-items:center;gap:72px}
.page-hero h1{
  max-width:820px;
  margin:18px 0 20px;
  font-size:clamp(52px,6.8vw,86px);
  line-height:.94;
  letter-spacing:-.06em;
}
.page-hero h1 span{color:var(--yellow)}
.page-hero p{max-width:690px;margin:0;color:var(--text-soft);font-size:19px}
.library-pulse{position:relative;width:330px;height:330px;margin:auto}
.pulse-orbit{position:absolute;border:1px solid rgba(86,216,255,.24);border-radius:50%}
.orbit-one{inset:28px}
.orbit-two{inset:74px;border-color:rgba(255,216,74,.25)}
.pulse-core{position:absolute;inset:116px;display:grid;place-items:center;border-radius:50%;background:var(--yellow);color:#11151d;font-weight:950;box-shadow:0 0 75px rgba(255,216,74,.22)}
.pulse-label{position:absolute;padding:6px 10px;border:1px solid var(--line);border-radius:999px;background:var(--surface);color:var(--text-soft);font-size:11px;font-weight:800}
.label-one{left:0;top:96px}
.label-two{right:4px;top:74px}
.label-three{right:18px;bottom:62px}
.library-grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:18px}
.library-card{
  position:relative;
  min-height:330px;
  display:flex;
  flex-direction:column;
  padding:28px;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  background:linear-gradient(145deg,var(--surface-2),var(--surface));
  text-decoration:none;
  transition:transform .2s ease,border-color .2s ease;
}
.library-card:hover{transform:translateY(-4px);border-color:var(--line-strong)}
.calculus-card{grid-column:span 7;background:radial-gradient(circle at 88% 15%,rgba(86,216,255,.15),transparent 18rem),linear-gradient(145deg,var(--surface-2),var(--surface))}
.geometry-card{grid-column:span 5;background:radial-gradient(circle at 85% 20%,rgba(255,127,159,.12),transparent 16rem),linear-gradient(145deg,var(--surface-2),var(--surface))}
.playground-card{grid-column:1/-1;min-height:250px;background:radial-gradient(circle at 82% 20%,rgba(169,149,255,.12),transparent 20rem),linear-gradient(145deg,var(--surface-2),var(--surface))}
.library-card-top{display:flex;align-items:start;justify-content:space-between;gap:16px;margin-bottom:34px}
.path-icon{font-family:Georgia,serif;color:var(--yellow);font-size:54px;line-height:1}
.status-badge{border-color:rgba(169,149,255,.28);background:rgba(169,149,255,.08);color:#c7baff}
.library-card h3{margin:8px 0 9px;font-size:clamp(30px,3vw,42px);line-height:1.05;letter-spacing:-.035em}
.library-card p{max-width:620px;margin:0;color:var(--muted)}
.module-chips{display:flex;gap:7px;flex-wrap:wrap;margin-top:22px}
.module-chips span{padding:5px 9px;border:1px solid var(--line);border-radius:999px;background:rgba(255,255,255,.025);color:var(--text-soft);font-size:10px;font-weight:750}
.library-card-foot{display:flex;align-items:center;justify-content:space-between;margin-top:auto;padding-top:28px;color:var(--text-soft);font-size:13px;font-weight:850}
.library-card-foot b{color:var(--yellow)}
.building-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}
.building-card{display:grid;grid-template-columns:44px 1fr;gap:15px;padding:22px;border:1px dashed var(--line-strong);border-radius:18px;background:rgba(12,17,27,.58)}
.building-card>span{color:var(--muted);font-size:11px;font-weight:900}
.building-card h3{margin:5px 0;font-size:20px}
.building-card p{margin:0;color:var(--muted);font-size:13px}
.rhythm-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px;margin:0;padding:0;list-style:none}
.rhythm-grid li{padding:26px;border-top:2px solid var(--line-strong);background:linear-gradient(180deg,rgba(18,25,39,.52),transparent)}
.rhythm-grid li>span{color:var(--yellow);font-size:12px;font-weight:900}
.rhythm-grid h3{margin:32px 0 6px;font-size:27px}
.rhythm-grid p{margin:0;color:var(--muted)}

/* Course path */
.path-help{display:flex;gap:8px 12px;flex-wrap:wrap;margin-top:28px;color:var(--muted);font-size:13px}
.path-help strong{color:var(--text-soft)}
.course-orbit{position:relative;width:340px;height:340px;margin:auto}
.orbit-ring{position:absolute;border:1px solid var(--line-strong);border-radius:50%}
.ring-one{inset:24px}
.ring-two{inset:78px;border-color:rgba(255,216,74,.28)}
.course-core{position:absolute;inset:126px;display:grid;place-items:center;border-radius:50%;background:var(--yellow);color:#11151d;font-family:Georgia,serif;font-size:42px;box-shadow:0 0 70px rgba(255,216,74,.24)}
.orbit-symbol{position:absolute;z-index:2;display:grid;place-items:center;width:58px;height:58px;border:1px solid var(--line-strong);border-radius:18px;background:var(--surface);font-family:Georgia,serif;font-size:22px}
.symbol-limit{left:0;top:135px;color:var(--cyan)}
.symbol-derivative{right:18px;top:35px;color:var(--pink)}
.symbol-integral{right:0;bottom:55px;color:var(--mint);font-size:33px}
.course-summary{border-bottom:1px solid var(--line);background:rgba(14,19,32,.58)}
.course-summary-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr))}
.course-summary-grid>div{display:grid;gap:1px;padding:24px 26px;border-left:1px solid var(--line)}
.course-summary-grid>div:last-child{border-right:1px solid var(--line)}
.course-summary strong{font-size:22px}
.course-summary span{color:var(--muted);font-size:11px}
.module-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}
.module-card{
  min-width:0;
  display:grid;
  grid-template-columns:48px 1fr;
  gap:15px;
  padding:22px;
  border:1px solid var(--line);
  border-radius:18px;
  background:var(--surface);
  text-decoration:none;
}
.module-card:hover{border-color:var(--line-strong)}
.module-letter{width:40px;height:40px;display:grid;place-items:center;border-radius:12px;background:rgba(255,255,255,.05);font-size:13px;font-weight:950}
.module-card.foundations .module-letter{color:var(--yellow)}
.module-card.limits-module .module-letter{color:var(--cyan)}
.module-card.derivatives-module .module-letter{color:var(--pink)}
.module-card.integrals-module .module-letter{color:var(--mint)}
.module-card h3{margin:4px 0;font-size:20px}
.module-card p{margin:0;color:var(--muted);font-size:12px}
.course-list{display:grid;gap:10px;counter-reset:lesson}
.path-item{
  position:relative;
  display:grid;
  grid-template-columns:58px 1fr auto;
  align-items:center;
  gap:18px;
  min-width:0;
  padding:16px 18px;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:17px;
  background:rgba(14,19,32,.84);
  text-decoration:none;
  scroll-margin-top:100px;
  transition:transform .16s ease,border-color .16s ease,background .16s ease;
}
.path-item::before{content:"";position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--line-strong)}
.path-item.foundations::before{background:var(--yellow)}
.path-item.limits-module::before{background:var(--cyan)}
.path-item.derivatives-module::before{background:var(--pink)}
.path-item.integrals-module::before{background:var(--mint)}
.path-item:hover{transform:translateX(4px);border-color:var(--line-strong);background:var(--surface-2)}
.path-num{width:42px;height:42px;display:grid;place-items:center;border:1px solid var(--line);border-radius:13px;color:var(--text-soft);font-size:11px;font-weight:900}
.path-module{display:block;margin-bottom:1px;color:var(--muted);font-size:10px;font-weight:900;letter-spacing:.1em;text-transform:uppercase}
.path-item strong{display:block;line-height:1.28}
.path-item small{display:block;margin-top:2px;color:var(--muted);line-height:1.35}
.status{color:var(--text-soft);font-size:11px;font-weight:850}
.status.start{color:var(--yellow)}
.status.soon{color:var(--muted)}
.course-cta{display:flex;align-items:center;justify-content:space-between;gap:28px;margin-top:24px;padding:26px;border:1px solid rgba(255,216,74,.22);border-radius:var(--radius);background:rgba(255,216,74,.055)}
.course-cta h3{margin:5px 0 0;font-size:23px}

/* Geometry */
.semicircle-scene{position:relative;width:390px;height:300px;margin:auto}
.semi-arc{
  position:absolute;
  width:300px;
  height:150px;
  left:45px;
  bottom:60px;
  border:4px solid var(--cyan);
  border-bottom:0;
  border-radius:300px 300px 0 0;
  box-shadow:0 0 28px rgba(86,216,255,.22);
}
.semi-base{position:absolute;left:45px;bottom:59px;width:300px;height:2px;background:var(--text-soft)}
.semi-height{position:absolute;left:195px;bottom:60px;width:3px;height:150px;background:var(--yellow);box-shadow:0 0 18px rgba(255,216,74,.25)}
.semi-point{position:absolute;left:188px;top:82px;width:17px;height:17px;border-radius:50%;background:var(--mint);box-shadow:0 0 20px var(--mint)}
.semi-a,.semi-b,.semi-gm{position:absolute;color:var(--text-soft);font-family:Georgia,serif;font-size:20px}
.semi-a{left:112px;bottom:27px}.semi-b{right:108px;bottom:27px}.semi-gm{left:210px;top:135px;color:var(--yellow)}
.geometry-feature{
  display:grid;
  grid-template-columns:72px 1fr auto;
  align-items:center;
  gap:26px;
  padding:34px;
  border:1px solid rgba(86,216,255,.22);
  border-radius:var(--radius-lg);
  background:radial-gradient(circle at 88% 25%,rgba(86,216,255,.13),transparent 19rem),linear-gradient(145deg,var(--surface-2),var(--surface));
  text-decoration:none;
}
.geometry-feature:hover{border-color:rgba(86,216,255,.42)}
.geometry-feature-number{width:58px;height:58px;display:grid;place-items:center;border:1px solid var(--line-strong);border-radius:16px;color:var(--yellow);font-weight:950}
.geometry-feature h3{margin:7px 0 8px;font-size:32px;line-height:1.08}
.geometry-feature p{max-width:690px;margin:0;color:var(--muted)}

/* Resource */
.resource-hero{min-height:calc(100vh - 72px);display:grid;align-items:center;padding:72px 0 84px}
.resource-grid{display:grid;grid-template-columns:minmax(0,.85fr) minmax(500px,1fr);align-items:center;gap:72px}
.resource-copy h1{margin:18px 0 20px;font-size:clamp(52px,6.2vw,82px);line-height:.94;letter-spacing:-.06em}
.resource-copy h1 span{color:var(--yellow)}
.resource-copy>p{max-width:610px;margin:0;color:var(--text-soft);font-size:19px}
.resource-points{display:grid;gap:12px;margin:34px 0 0;padding:0;list-style:none}
.resource-points li{display:flex;align-items:center;gap:14px;color:var(--text-soft)}
.resource-points span{width:36px;height:28px;display:grid;place-items:center;border:1px solid var(--line);border-radius:9px;color:var(--yellow);font-size:10px;font-weight:900}
.pack-card{display:grid;grid-template-columns:220px 1fr;align-items:center;gap:28px;padding:28px;border:1px solid var(--line);border-radius:var(--radius-lg);background:linear-gradient(145deg,var(--surface-2),var(--surface));box-shadow:var(--shadow)}
.pack-preview{position:relative;height:360px}
.pack-sheet{position:absolute;inset:18px 8px;border-radius:12px}
.sheet-back{transform:rotate(-6deg);background:#dfe6f0;opacity:.35}
.sheet-front{
  display:flex;
  flex-direction:column;
  padding:22px;
  overflow:hidden;
  background:#f5f1df;
  color:#11151d;
  transform:rotate(2deg);
  box-shadow:0 18px 40px rgba(0,0,0,.3);
}
.sheet-brand{font-size:8px;font-weight:950;letter-spacing:.16em}
.sheet-front>strong{margin-top:28px;font-size:25px;line-height:.98;letter-spacing:-.04em}
.sheet-front>span{margin-top:9px;font-size:9px}
.sheet-graph{position:relative;height:130px;margin-top:auto;border-left:1px solid #747b88;border-bottom:1px solid #747b88}
.sheet-graph i{position:absolute;left:7%;top:48%;width:90%;height:3px;background:#149bc3;transform:rotate(-26deg)}
.sheet-graph b{position:absolute;left:55%;top:34%;width:14px;height:14px;border:3px solid #e6a900;border-radius:50%;background:#f5f1df}
.sheet-graph em{position:absolute;left:30%;top:51%;width:10px;height:10px;border-radius:50%;background:#17b47c}
.pack-form-wrap h2{margin:5px 0 20px;font-size:29px;line-height:1.08}

/* module: 30-lesson.css */
/* Lesson */
.breadcrumbs{
  display:flex;
  align-items:center;
  gap:8px;
  padding-top:18px;
  color:var(--muted);
  font-size:12px;
  white-space:nowrap;
  overflow-x:auto;
  scrollbar-width:none;
}
.breadcrumbs::-webkit-scrollbar{display:none}
.breadcrumbs a{text-decoration:none}
.breadcrumbs a:hover{color:var(--text)}
.breadcrumbs>span:last-child{overflow:hidden;text-overflow:ellipsis}
.lesson-jumpbar{display:none}
.lesson-section{padding:20px 0 88px}
.lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) 288px;gap:48px;align-items:start}
.lesson-main{min-width:0}
.lesson-header{max-width:860px}
.lesson-progress{display:flex;align-items:center;gap:12px;margin-bottom:18px;color:var(--text-soft);font-size:11px;font-weight:850;letter-spacing:.07em;text-transform:uppercase}
.progress-track{width:118px;height:4px;overflow:hidden;border-radius:99px;background:rgba(255,255,255,.08)}
.progress-track>span{display:block;height:100%;border-radius:99px;background:var(--yellow)}
.lesson-header h1{max-width:700px;margin:10px 0 14px;font-size:clamp(46px,4.6vw,60px);line-height:.98;letter-spacing:-.052em}
.lede{max-width:760px;margin:0;color:var(--text-soft);font-size:18px}
.lesson-objective{
  display:grid;
  gap:4px;
  margin:16px 0;
  padding:13px 18px;
  border-left:3px solid var(--yellow);
  border-radius:0 13px 13px 0;
  background:rgba(255,216,74,.055);
}
.lesson-objective span{color:var(--yellow);font-size:10px;font-weight:900;letter-spacing:.12em;text-transform:uppercase}
.lesson-objective strong{font-size:14px}
.formula{
  margin:16px 0 20px;
  padding:17px 22px;
  overflow-x:auto;
  overflow-y:hidden;
  border:1px solid var(--line);
  border-radius:16px;
  background:linear-gradient(145deg,#0b101a,#0a0d15);
  text-align:center;
  font-family:Georgia,"Times New Roman",serif;
  font-size:clamp(21px,2.8vw,31px);
  line-height:1.18;
  white-space:normal;
}
.math-expression{display:inline-flex;max-width:100%;align-items:center;justify-content:center;column-gap:.18em;row-gap:.52em;flex-wrap:wrap;vertical-align:middle}
.math-frac{display:inline-grid;grid-template-rows:auto auto;align-items:center;justify-items:center;vertical-align:middle;line-height:.94;margin:0 .1em;transform:translateY(.03em)}
.math-num{min-width:100%;padding:0 .16em .09em;border-bottom:1.35px solid currentColor;text-align:center}
.math-den{padding:.09em .16em 0;text-align:center}
.math-root{display:inline-flex;align-items:flex-start;vertical-align:middle}
.math-radical{font-size:1.12em;line-height:1}
.math-radicand{padding:.02em .12em 0;border-top:1.35px solid currentColor}
.math-expression sup,.math-expression sub{font-size:.58em;line-height:0}
.math-derivation{display:flex;width:100%;align-items:center;justify-content:center;gap:.48em .7em;flex-wrap:wrap;white-space:normal}
.math-line{display:inline-flex;align-items:center;justify-content:center;gap:.11em;white-space:nowrap;line-height:1.12}
.math-line var{font-style:italic}
.math-line sup{position:relative;top:-.34em;font-size:.58em;line-height:0}
.math-fn{font-style:normal;letter-spacing:.01em}
.math-implies,.math-separator{display:inline-grid;place-items:center;flex:none;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1}
.math-implies{padding:0 .05em;color:var(--yellow);font-size:.92em;font-weight:850}
.math-separator{color:var(--muted);font-size:.82em;font-weight:800}
.limit-op{display:inline-flex;min-width:1.6em;flex-direction:column;align-items:center;justify-content:center;vertical-align:middle;line-height:.74;margin:0 .1em;transform:translateY(.035em)}
.limit-op>span{font-style:normal}
.limit-op sub{position:static;font-size:.41em;line-height:1.05;margin-top:.3em;white-space:nowrap}
.interactive,.quiz,[id^="explain-"],#aha{scroll-margin-top:100px}
.lesson-interactive{
  margin:0 0 24px;
  padding:20px;
  border:1px solid rgba(85,191,255,.28);
  border-radius:var(--radius);
  background:linear-gradient(145deg,rgba(16,26,42,.99),rgba(7,12,21,.99));
  box-shadow:0 24px 70px rgba(0,0,0,.22);
}
.lesson-interactive canvas{height:auto;aspect-ratio:16/9}
.interactive-top h2{font-size:24px}
.touch-hint{min-height:36px;display:inline-flex;align-items:center;padding:6px 12px;border:1px solid var(--line);border-radius:999px;color:var(--text-soft);font-size:11px;font-weight:800}
.aha-callout{
  display:grid;
  gap:7px;
  margin:28px 0;
  padding:22px 24px;
  border:1px solid rgba(255,216,74,.27);
  border-radius:18px;
  background:linear-gradient(135deg,rgba(255,216,74,.09),rgba(255,216,74,.035));
}
.aha-callout p{margin:0;color:var(--text);font-size:clamp(18px,2.2vw,23px);font-weight:750;line-height:1.4}
.explain-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin:22px 0 64px}
.explain-card{min-width:0;padding:20px;border-top:2px solid var(--line-strong);background:linear-gradient(180deg,rgba(18,25,39,.55),transparent)}
.section-index{color:var(--muted);font-size:9px;font-weight:900}
.explain-card h2{margin:26px 0 7px;font-size:21px;line-height:1.14;letter-spacing:-.02em}
.explain-card p{margin:0;color:var(--muted);font-size:13px}
.practice-section{margin:0 0 58px}
.practice-section>h2{margin:7px 0 18px;font-size:clamp(29px,3.4vw,40px);line-height:1.08;letter-spacing:-.035em}
.practice-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}
.practice-card{padding:20px;border:1px solid var(--line);border-radius:16px;background:linear-gradient(180deg,rgba(18,25,39,.72),rgba(10,14,23,.88))}
.practice-card.is-correct{border-color:rgba(101,230,180,.4)}
.practice-card h3{margin:8px 0 15px;font-size:18px;line-height:1.35}
.practice-options{display:grid;gap:8px}
.practice-options button{min-height:44px;padding:11px 13px;border:1px solid var(--line);border-radius:11px;background:#0b101a;color:var(--text-soft);text-align:left;cursor:pointer}
.practice-options button:hover{border-color:var(--line-strong);color:var(--text)}
.practice-card .feedback{min-height:22px;margin-top:10px;font-size:12px;line-height:1.45}
.lesson-search-support{display:grid;gap:54px;margin:6px 0 64px}
.lesson-search-support h2{margin:7px 0 12px;font-size:clamp(30px,3.6vw,42px);line-height:1.05;letter-spacing:-.035em}
.lesson-search-support p{color:var(--text-soft)}
.seo-definition{max-width:800px;padding:24px;border-left:3px solid var(--cyan);border-radius:0 16px 16px 0;background:rgba(86,216,255,.05)}
.seo-definition p{margin:0;font-size:17px;line-height:1.65}
.seo-table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:16px;background:var(--surface)}
.seo-table-wrap table{width:100%;border-collapse:collapse;min-width:680px}
.seo-table-wrap th,.seo-table-wrap td{padding:16px 18px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
.seo-table-wrap th{color:var(--yellow);font-size:11px;letter-spacing:.06em;text-transform:uppercase;background:rgba(255,255,255,.025)}
.seo-table-wrap td{color:var(--text-soft);font-size:14px;line-height:1.55}
.seo-table-wrap tr:last-child td{border-bottom:0}
.seo-visual-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
.seo-figure{margin:0;overflow:hidden;border:1px solid var(--line);border-radius:18px;background:var(--surface)}
.seo-figure img{display:block;width:100%;height:auto;background:#090e17}
.seo-figure figcaption{padding:13px 16px;color:var(--muted);font-size:12px;line-height:1.5}
.seo-steps ol{display:grid;gap:10px;margin:18px 0 0;padding:0;list-style:none}
.seo-steps li{display:grid;grid-template-columns:42px 1fr;gap:14px;padding:16px 18px;border:1px solid var(--line);border-radius:14px;background:rgba(255,255,255,.018)}
.seo-steps li>span{display:grid;place-items:center;width:34px;height:34px;border-radius:50%;background:rgba(255,216,74,.08);color:var(--yellow);font-size:10px;font-weight:900}
.seo-steps strong{display:block;margin-bottom:4px}
.seo-steps p{margin:0;font-size:13px}
.seo-example-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}
.seo-example{padding:20px;border:1px solid var(--line);border-radius:16px;background:linear-gradient(180deg,rgba(18,25,39,.72),rgba(10,14,23,.86))}
.seo-example h3{margin:8px 0 12px;font-size:19px}
.seo-example-formula{min-height:62px;display:flex;align-items:center;overflow-x:auto;padding:12px;border-radius:11px;background:#080d15;font-family:Georgia,"Times New Roman",serif;font-size:18px;white-space:nowrap}
.seo-example p{margin:12px 0 0;font-size:13px;line-height:1.55}
.seo-faq{max-width:860px}
.seo-faq details{border-top:1px solid var(--line)}
.seo-faq details:last-child{border-bottom:1px solid var(--line)}
.seo-faq summary{padding:16px 2px;cursor:pointer;color:var(--text);font-weight:800}
.seo-faq details p{margin:0;padding:0 2px 18px;font-size:14px;line-height:1.6}
.quiz-section{margin-top:12px}
.quiz-section>h2{margin:7px 0 18px;font-size:clamp(32px,4vw,46px);line-height:1.05;letter-spacing:-.04em}
.quiz{
  margin:0;
  padding:22px;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--surface);
}
.quiz h3{margin:0;font-size:20px;line-height:1.35}
.quiz-options{display:grid;gap:10px;margin-top:18px}
.quiz button{
  width:100%;
  min-height:48px;
  padding:13px 15px;
  border:1px solid var(--line);
  border-radius:12px;
  background:#0b101a;
  color:var(--text-soft);
  text-align:left;
  cursor:pointer;
  transition:border-color .15s ease,background .15s ease,color .15s ease;
}
.quiz button:hover{border-color:var(--line-strong);background:var(--surface-2);color:var(--text)}
.next-card{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:22px;
  margin-top:24px;
  padding:24px;
  border:1px solid rgba(86,216,255,.23);
  border-radius:var(--radius);
  background:linear-gradient(135deg,rgba(86,216,255,.08),rgba(86,216,255,.025));
  text-decoration:none;
}
.next-card strong{display:block;margin-top:4px}
.next-card:hover{border-color:rgba(86,216,255,.45)}
.next-arrow{width:42px;height:42px;display:grid;place-items:center;flex:none;border:1px solid rgba(86,216,255,.25);border-radius:50%;color:var(--cyan)}
.aside{
  position:sticky;
  top:94px;
  padding:22px;
  border:1px solid var(--line);
  border-radius:18px;
  background:rgba(14,19,32,.9);
}
.aside-label{margin-bottom:13px;color:var(--text-soft);font-size:11px;font-weight:900}
.aside .lesson-progress{display:block;margin-bottom:16px}
.aside .progress-track{display:block;width:100%;margin-top:7px}
.aside>a{display:flex;align-items:center;gap:10px;min-height:44px;padding:9px 0;color:var(--muted);text-decoration:none;font-size:13px}
.aside>a>span{width:24px;color:var(--yellow);font-size:9px;font-weight:900}
.aside>a:hover{color:var(--text)}
.aside hr{border:0;border-top:1px solid var(--line);margin:13px 0}
.aside .aside-back{color:var(--text-soft)}
.aside .aside-pack{margin-top:8px;padding:11px;border:1px solid rgba(255,216,74,.22);border-radius:11px;background:rgba(255,216,74,.06);color:var(--yellow-soft)}

.aside>a.is-active{color:var(--text);font-weight:800}
.aside>a.is-active>span{color:var(--yellow)}
.lesson-page .control-block{margin-top:16px}
.lesson-page .control-label{margin:0 0 5px;color:var(--text-soft);font-size:14px;font-weight:800}

/* module: 40-shell.css */
/* Footer */
.footer{border-top:1px solid var(--line);padding:34px 0 44px;background:rgba(5,7,12,.58)}
.footer-inner{display:flex;align-items:center;gap:28px}
.footer-brand{font-size:13px}
.footer-inner>p{margin:0;color:var(--muted);font-size:12px}
.footer-inner nav{display:flex;gap:18px;margin-left:auto}
.footer-inner nav a{color:var(--muted);text-decoration:none;font-size:12px;font-weight:750}
.footer-inner nav a:hover{color:var(--text)}

/* module: 50-responsive.css */
/* Responsive */
@media(max-width:1080px){
  .hero-grid{grid-template-columns:minmax(0,.82fr) minmax(470px,1.08fr);gap:42px}
  .route-grid{gap:52px}
  .module-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .resource-grid{grid-template-columns:minmax(0,.8fr) minmax(470px,1fr);gap:42px}
}
@media(max-width:920px){
  .home-hero{padding-top:62px}
  .hero-grid,.page-hero-grid,.resource-grid{grid-template-columns:1fr}
  .hero-grid{gap:48px}
  .hero-lab{max-width:680px}
  .page-hero-grid{gap:34px}
  .library-pulse,.course-orbit,.semicircle-scene{transform:scale(.88);transform-origin:center}
  .page-hero-grid>div:last-child{min-height:260px}
  .resource-grid{max-width:760px}
  .pack-card{grid-template-columns:220px 1fr}
  .topic-grid{grid-template-columns:1fr}
  .topic-card{display:grid;grid-template-columns:42% 1fr;align-items:center}
  .topic-art{height:auto;min-height:0;aspect-ratio:16/9;border-bottom:0;border-right:1px solid var(--line)}
  .route-grid{grid-template-columns:1fr;gap:36px}
  .track-grid{grid-template-columns:1fr}
  .track-featured{grid-row:auto;min-height:300px}
  .pack-banner{grid-template-columns:140px 1fr}
  .pack-banner>.btn{grid-column:2}
  .library-card{grid-column:1/-1}
  .building-grid{grid-template-columns:1fr}
  .lesson-layout{grid-template-columns:1fr}
  .aside{display:none}
  .lesson-jumpbar{position:relative;z-index:1;display:flex;gap:8px;padding-block:12px;background:rgba(6,11,19,.92)}
  .lesson-jumpbar a{flex:1;min-height:48px;display:grid;place-items:center;border:1px solid var(--line);border-radius:12px;background:var(--surface);color:var(--text-soft);text-decoration:none;font-size:12px;font-weight:800}
  .lesson-jumpbar a.is-active{border-color:rgba(255,216,74,.65);background:rgba(255,216,74,.08);color:var(--yellow)}
  .lesson-page .breadcrumbs{display:none}
  .lesson-interactive canvas{height:auto;aspect-ratio:16/9}
}
@media(max-width:760px){
  .wrap{width:calc(100% - 32px)}
  .nav{min-height:64px;gap:14px}
  .nav-links{display:none}
  .nav-cta{margin-left:auto;min-height:40px;padding-inline:11px;font-size:11px}
  .brand-daily{display:inline-flex}
  .section{padding:66px 0}
  .section-head{display:block;margin-bottom:24px}
  .section-head>p{margin-top:12px}
  .section-head h2,.section h2{font-size:36px}
  .home-hero{padding:42px 0 48px}
  .hero-grid{gap:40px}
  .hero-copy h1{font-size:clamp(50px,14.8vw,64px)}
  .hero-lede{font-size:17px}
  .hero-facts{gap:8px;margin-top:30px}
  .hero-facts li{grid-template-columns:40px minmax(0,1fr);gap:8px}
  .fact-icon{width:40px;height:40px}
  .fact-icon svg{width:20px;height:20px}
  .hero-facts strong{font-size:18px}
  .hero-facts .fact-copy>span{font-size:12px}
  .signal-inner{gap:12px;justify-content:flex-start;overflow-x:auto;white-space:nowrap}
  .topic-card{display:block}
  .topic-art{height:auto;min-height:0;aspect-ratio:16/9;border-right:0;border-bottom:1px solid var(--line)}
  .route-copy h2{font-size:42px}
  .track-card{grid-template-columns:38px 1fr auto;min-height:230px;padding:22px}
  .track-featured{min-height:300px}
  .pack-banner{grid-template-columns:1fr;padding:28px}
  .pack-orbit{width:120px;height:120px;margin:0}
  .pack-banner>.btn{grid-column:auto;width:100%}
  .page-hero{padding:60px 0 52px}
  .page-hero h1{font-size:clamp(46px,14vw,66px)}
  .page-hero p{font-size:17px}
  .page-hero-grid>div:last-child{min-height:230px}
  .library-pulse,.course-orbit,.semicircle-scene{transform:scale(.72)}
  .course-summary-grid{grid-template-columns:repeat(2,1fr)}
  .course-summary-grid>div{border-bottom:1px solid var(--line)}
  .course-summary-grid>div:nth-child(2n){border-right:1px solid var(--line)}
  .module-grid{grid-template-columns:1fr}
  .path-item{grid-template-columns:48px 1fr;padding:14px}
  .path-item .status{display:none}
  .course-cta{display:block}
  .course-cta .btn{width:100%;margin-top:18px}
  .geometry-feature{grid-template-columns:54px 1fr;padding:22px}
  .geometry-feature>.track-arrow{display:none}
  .resource-hero{min-height:auto;padding:56px 0 68px}
  .resource-copy h1{font-size:clamp(46px,14vw,66px)}
  .resource-copy>p{font-size:17px}
  .pack-card{grid-template-columns:1fr}
  .pack-preview{height:300px;max-width:220px;width:100%;margin:auto}
  .explain-grid{grid-template-columns:1fr;margin-bottom:50px}
  .explain-card h2{margin-top:18px}
  .practice-grid{grid-template-columns:1fr}
  .seo-visual-grid,.seo-example-grid{grid-template-columns:1fr}
  .lesson-search-support{gap:42px;margin-bottom:52px}
  .seo-definition{padding:20px}
  .lesson-section{padding-top:22px}
  .lesson-header h1{font-size:clamp(40px,11.5vw,48px)}
  .lesson-header .lede{font-size:16px}
  .lesson-objective{margin-block:20px;padding:15px 16px}
  .controls{grid-template-columns:1fr}
  .readout{min-width:0}
  .lesson-interactive,.quiz{padding:16px}
  .touch-hint{display:none}
  .footer-inner{align-items:flex-start;flex-direction:column;gap:14px}
  .footer-inner nav{margin-left:0;flex-wrap:wrap}
  .card,.card.third{grid-column:1/-1}
}
@media(max-width:480px){
  .hero-actions{display:grid;grid-template-columns:1fr;width:100%}
  .hero-actions .btn{width:100%}
  .hero-actions .text-link{justify-content:center;min-height:44px}
  .hero-lab{padding:13px;border-radius:22px}
  .stage-top h2{font-size:18px}
  .live-pill{display:inline-flex}
  .topic-copy{padding:21px}
  .topic-copy h3{font-size:23px}
  .method-steps li{grid-template-columns:38px 1fr;padding:17px}
  .track-card{grid-template-columns:30px 1fr;padding:19px}
  .track-arrow{display:none}
  .library-card{min-height:300px;padding:22px}
  .library-card-top{margin-bottom:26px}
  .library-card h3{font-size:31px}
  .rhythm-grid{grid-template-columns:1fr}
  .rhythm-grid li{padding:20px}
  .rhythm-grid h3{margin-top:18px}
  .course-summary-grid>div{padding:18px}
  .geometry-feature{grid-template-columns:1fr}
  .geometry-feature-number{width:48px;height:48px}
  .lesson-progress{align-items:flex-start;flex-direction:column;gap:7px}
  .lesson-jumpbar{gap:6px}
  .lesson-jumpbar a{font-size:11px}
  .lesson-header h1{font-size:42px}
  .lede{font-size:16px}
  .formula{padding:16px;font-size:20px;line-height:1.35;white-space:normal;overflow-wrap:break-word}
  .math-derivation{display:grid;justify-items:center;gap:8px}
  .math-line{white-space:normal}
  .math-implies{font-size:24px;line-height:1}
  .interactive-top h2{font-size:21px}
  .aha-callout{padding:18px}
  .next-card{padding:19px}
  .next-arrow{width:36px;height:36px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}
}
@media print{
  .site-header,.lesson-jumpbar,.no-print,.footer{display:none!important}
  body{background:#fff;color:#111}
  body::before{display:none}
  .wrap{width:100%}
  .aha-list>div{break-inside:avoid;background:#fff;border-color:#ccc}
  .aha-list span{color:#333}
}

@media(max-width:600px){
  .nav{gap:10px}
  .brand{gap:7px}
  .brand-mark{width:34px;height:34px}
  .nav-cta{font-size:10px;padding-inline:10px}
  .hero-actions{margin-top:24px}
  .home-page .hero-actions{gap:10px}
  .start-section{padding-top:34px}
  .lesson-progress{margin-bottom:16px}
  .lesson-header .eyebrow{font-size:11px}
  .lesson-interactive .interactive-top{align-items:center}
}
@media(max-width:360px){
  .brand-daily{display:none}
  .nav-cta{padding-inline:9px}
  .hero-facts li{display:block;text-align:center}
  .fact-icon{margin:0 auto 7px}
}

/* module: 60-auxiliary.css */
/* business/learning system v2 (superseded by aha-lab v4) */
/* learning UX v3 (superseded by aha-lab v4) */
/* production visual + SEO finish v1 */
.module-hero{padding-top:64px}
.module-orbit{position:relative;min-height:320px;border:1px solid var(--line);border-radius:24px;overflow:hidden;background-color:#090c14;background-image:linear-gradient(rgba(255,255,255,.035) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.035) 1px,transparent 1px);background-size:32px 32px;box-shadow:0 26px 70px rgba(0,0,0,.32)}
.orbit-axis-x,.orbit-axis-y{position:absolute;background:#4c5670}.orbit-axis-x{left:8%;right:8%;top:58%;height:2px}.orbit-axis-y{top:9%;bottom:9%;left:52%;width:2px}
.orbit-curve{position:absolute;left:7%;right:7%;top:49%;height:58px;border-top:5px solid var(--cyan);border-radius:50%;transform:rotate(-10deg);filter:drop-shadow(0 0 14px rgba(86,184,255,.24))}
.orbit-hole{position:absolute;left:calc(52% - 11px);top:calc(52% - 11px);width:18px;height:18px;border:4px solid var(--yellow);border-radius:50%;background:#090c14;box-shadow:0 0 0 7px rgba(255,217,61,.08)}
.orbit-near{position:absolute;top:53%;width:10px;height:10px;border-radius:50%;background:var(--mint);box-shadow:0 0 18px rgba(101,230,180,.7)}.orbit-near.left{left:33%}.orbit-near.right{right:28%}
.module-orbit em{position:absolute;right:24px;bottom:20px;color:var(--yellow);font-size:13px;font-weight:850;font-style:normal;letter-spacing:.08em}
.module-lessons{display:grid;gap:12px;max-width:920px}.module-lessons .path-item{grid-template-columns:64px minmax(0,1fr) auto}
.module-outcome{max-width:920px;margin-top:24px;padding:28px;border:1px solid var(--line);border-radius:20px;background:var(--surface-1)}.module-outcome ul{margin:16px 0 22px;padding-left:22px;color:var(--text-soft)}.module-outcome li+li{margin-top:8px}
.bio-page{min-height:100vh;background-color:#070910;background-image:radial-gradient(circle at 50% -10%,rgba(86,184,255,.12),transparent 36%),linear-gradient(rgba(255,255,255,.025) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.025) 1px,transparent 1px);background-size:auto,32px 32px,32px 32px}
.bio-shell{width:min(100% - 32px,580px);margin:0 auto;padding:38px 0 42px}
.bio-brand{width:max-content;margin-bottom:74px}.bio-kicker{color:var(--cyan);font-size:11px;font-weight:900;letter-spacing:.16em;text-transform:uppercase}
.bio-shell h1{margin:13px 0 14px;font-size:clamp(44px,10vw,68px);line-height:.96;letter-spacing:-.055em}.bio-shell h1 span{color:var(--yellow)}
.bio-intro{max-width:490px;margin:0 0 30px;color:var(--text-soft);font-size:16px}
.bio-links{display:grid;gap:12px}.bio-link{display:grid;grid-template-columns:48px minmax(0,1fr) auto;gap:14px;align-items:center;padding:17px 18px;border:1px solid var(--line);border-radius:16px;background:rgba(16,20,31,.9);color:var(--text);text-decoration:none;transition:transform .16s,border-color .16s,background .16s}
.bio-link:hover{transform:translateY(-2px);border-color:var(--line-strong);background:#131827}.bio-link.primary{border-color:rgba(255,217,61,.48);background:linear-gradient(120deg,rgba(255,217,61,.13),rgba(16,20,31,.95) 58%)}
.bio-symbol{display:grid;place-items:center;width:48px;height:48px;border:1px solid var(--line-strong);border-radius:12px;color:var(--yellow);font-size:25px;font-weight:800;background:#090c14}.bio-link strong,.bio-link small{display:block}.bio-link strong{font-size:15px}.bio-link small{margin-top:3px;color:var(--muted);font-size:12px;line-height:1.35}.bio-link>b{color:var(--yellow)}
.bio-socials{display:flex;gap:8px;margin-top:16px}.bio-socials a{flex:1;padding:12px 8px;border:1px solid var(--line);border-radius:12px;color:var(--text-soft);text-align:center;text-decoration:none;font-size:12px;font-weight:800}.bio-socials a:hover{border-color:var(--line-strong);color:var(--text)}
.bio-footer{display:flex;justify-content:space-between;margin-top:54px;padding-top:16px;border-top:1px solid var(--line);color:var(--muted);font-size:11px;font-weight:800;letter-spacing:.1em;text-transform:uppercase}
.not-found{display:grid;min-height:calc(100vh - 74px);place-items:center;padding:64px 0}.not-found-grid{display:grid;grid-template-columns:minmax(0,1fr) 380px;gap:72px;align-items:center}.not-found h1{max-width:720px;margin:14px 0;font-size:clamp(48px,7vw,88px);line-height:.94;letter-spacing:-.055em}.not-found p{max-width:630px;color:var(--text-soft);font-size:18px}
.missing-plot{position:relative;min-height:330px;border:1px solid var(--line);border-radius:24px;overflow:hidden;background-color:#090c14;background-image:linear-gradient(rgba(255,255,255,.035) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.035) 1px,transparent 1px);background-size:32px 32px}.missing-x,.missing-y{position:absolute;background:#4c5670}.missing-x{left:8%;right:8%;top:62%;height:2px}.missing-y{top:9%;bottom:9%;left:48%;width:2px}.missing-curve{position:absolute;left:8%;right:8%;top:44%;height:65px;border-top:5px solid var(--cyan);border-radius:50%;transform:rotate(-11deg)}.missing-plot i{position:absolute;left:calc(48% - 10px);top:calc(56% - 10px);width:18px;height:18px;border:4px solid var(--yellow);border-radius:50%;background:#090c14}.missing-plot b{position:absolute;right:24px;bottom:18px;color:var(--yellow);font-size:54px}
.deep-dive,.lesson-video{margin-top:44px}.deep-dive>h2,.lesson-video>h2{margin:8px 0 10px;font-size:clamp(27px,3vw,38px)}.deep-dive-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:18px}.deep-dive-card{padding:22px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1)}.deep-dive-card h3{margin:0 0 8px;font-size:17px}.deep-dive-card p,.lesson-video>p,.related-tool p{margin:0;color:var(--text-soft)}
.video-frame{position:relative;overflow:hidden;margin-top:18px;border:1px solid var(--line);border-radius:20px;background:#02040a;aspect-ratio:16/9}.video-frame iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.related-tool{display:flex;align-items:center;justify-content:space-between;gap:26px;margin-top:28px;padding:24px}.related-tool h2{margin:5px 0 7px;font-size:22px}.related-tool .btn{flex:none}
.tool-page .page-hero{padding-bottom:42px}.tool-hero-copy{max-width:800px}.tool-hero-copy h1{font-size:clamp(44px,6vw,78px);line-height:.98;letter-spacing:-.05em}.tool-hero-copy p{max-width:720px;color:var(--text-soft);font-size:18px}.tool-grid{display:grid;grid-template-columns:minmax(0,1.55fr) minmax(280px,.65fr);gap:22px;align-items:start}.tool-panel{padding:22px}.tool-panel canvas{display:block;width:100%;height:auto;border:1px solid var(--line);border-radius:16px;background:#080d16}.tool-controls{display:grid;gap:12px;margin-bottom:16px}.riemann-controls{grid-template-columns:minmax(180px,2fr) repeat(4,minmax(80px,.7fr))}.tangent-controls{grid-template-columns:minmax(180px,1.6fr) minmax(100px,.55fr) minmax(220px,1fr)}.tool-controls label{display:grid;gap:7px;color:var(--muted);font-size:12px;font-weight:800;letter-spacing:.04em}.tool-controls input,.tool-controls select{width:100%;min-height:44px;padding:10px 12px;border:1px solid var(--line-strong);border-radius:10px;background:#090d16;color:var(--text);font:inherit}.tool-controls input[type=range]{padding:0}.tool-result{display:grid;gap:10px;margin-top:16px}.tool-result>div{display:flex;justify-content:space-between;gap:16px;padding:12px 14px;border:1px solid var(--line);border-radius:12px;background:rgba(255,255,255,.02)}.tool-result span{color:var(--muted);font-size:13px}.tool-result strong{font-size:14px;text-align:right}.tool-result small{color:var(--muted)}.tool-error{min-height:24px;margin:10px 0 0;color:#ff8d8d;font-size:13px}.tool-side{display:grid;gap:14px}.tool-note{padding:20px;border:1px solid var(--line);border-radius:16px;background:var(--surface-1)}.tool-note h2,.tool-note h3{margin:0 0 8px}.tool-note p,.tool-note li{color:var(--text-soft)}.tool-note ul{margin:10px 0 0;padding-left:20px}.tool-note code{color:var(--yellow)}.tool-explain{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.tool-explain article{padding:22px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1)}.tool-explain h2{font-size:19px}.tool-explain p{color:var(--text-soft)}.tool-cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.tool-cards-three{grid-template-columns:repeat(3,minmax(0,1fr))}.featured-practice-card{border-color:rgba(255,217,61,.34);background:linear-gradient(145deg,rgba(255,217,61,.08),var(--surface-1) 58%)}.tool-card{display:block;padding:24px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1);color:var(--text);text-decoration:none}.tool-card:hover{border-color:var(--line-strong);transform:translateY(-2px)}.tool-card .meta{margin-bottom:8px}.tool-card h2{margin:0 0 8px}.tool-card p{margin:0;color:var(--text-soft)}
.practice-section{padding-top:10px}.unit-practice-shell{display:grid;gap:16px}.practice-toolbar{display:grid;grid-template-columns:minmax(220px,.65fr) auto minmax(0,1.4fr);gap:16px;align-items:end;padding:16px 18px}.practice-toolbar label{display:grid;gap:7px;color:var(--muted);font-size:12px;font-weight:850;letter-spacing:.04em}.practice-toolbar select{min-height:44px;padding:10px 12px;border:1px solid var(--line-strong);border-radius:10px;background:#090d16;color:var(--text);font:inherit}.practice-reset{min-height:44px}.practice-stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.practice-stats div{padding:8px 12px;border-left:1px solid var(--line)}.practice-progress-track{grid-column:1/-1;height:5px;overflow:hidden;border-radius:999px;background:rgba(255,255,255,.06)}.practice-progress-track span{display:block;width:0;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--cyan),var(--mint));transition:width .22s ease}.practice-stats span,.practice-stats strong{display:block}.practice-stats span{color:var(--muted);font-size:10px;font-weight:800;letter-spacing:.05em;text-transform:uppercase}.practice-stats strong{margin-top:3px;font-size:17px}.unit-practice-grid{display:grid;grid-template-columns:minmax(320px,.95fr) minmax(0,1.05fr);gap:18px;align-items:stretch}.unit-circle-card,.practice-question-card{padding:22px}.unit-circle-card{display:grid;align-content:start}.unit-circle-viz{overflow:hidden;border:1px solid var(--line);border-radius:18px;background:radial-gradient(circle at 50% 50%,rgba(86,184,255,.055),transparent 52%),#080d16}.unit-circle-viz svg{display:block;width:100%;height:auto}.uc-ring{fill:none;stroke:#3b4960;stroke-width:3}.uc-axis{stroke:#334057;stroke-width:2}.uc-diagonal{stroke:#222d3f;stroke-width:1;stroke-dasharray:7 8;transition:opacity .16s ease}.uc-ray{stroke:var(--yellow);stroke-width:6;stroke-linecap:round;transition:opacity .16s ease}.uc-point{fill:var(--mint);stroke:#071018;stroke-width:4}.uc-angle-arc{fill:none;stroke:var(--cyan);stroke-width:4;stroke-linecap:round;transition:opacity .16s ease}.uc-axis-label{fill:#758198;font-size:16px;font-weight:800}.uc-angle-label{fill:var(--yellow);font-size:20px;font-weight:900}.uc-coordinate-label{fill:var(--mint);font-size:16px;font-weight:850}.practice-visual-note{padding:12px 4px 0;color:var(--muted);font-size:13px}.practice-question-card{display:flex;flex-direction:column}.practice-question-card h2{margin:8px 0 8px;font-size:clamp(26px,3vw,38px);line-height:1.05}.practice-help{margin:0 0 20px;color:var(--text-soft)}.practice-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.practice-option{min-height:64px;padding:13px 14px;border:1px solid var(--line-strong);border-radius:14px;background:#0a0f19;color:var(--text);font:inherit;font-size:15px;font-weight:800;text-align:left;cursor:pointer;transition:border-color .16s,transform .16s,background .16s}.practice-option:hover:not(:disabled){transform:translateY(-1px);border-color:#728099}.practice-option[data-state="wrong"]{border-color:rgba(255,120,120,.58);background:rgba(255,100,100,.08)}.practice-option[data-state="correct"]{border-color:rgba(101,230,180,.65);background:rgba(101,230,180,.09)}.practice-option:disabled{cursor:default}.practice-feedback{min-height:48px;margin-top:14px;padding:12px 14px;border-radius:12px;background:rgba(255,255,255,.025);color:var(--text-soft);font-size:14px}.practice-feedback.correct{color:var(--mint)}.practice-feedback.wrong{color:#ffadad}.practice-next{align-self:flex-start;margin-top:12px}.practice-next[hidden],.practice-complete[hidden]{display:none!important}.practice-complete{margin-top:auto;padding-top:22px}.practice-complete h3{margin:7px 0 7px;font-size:28px}.practice-complete p{color:var(--text-soft)}.unit-value-table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:18px}.unit-value-table{width:100%;border-collapse:collapse;min-width:660px;background:var(--surface-1)}.unit-value-table th,.unit-value-table td{padding:14px 16px;border-bottom:1px solid var(--line);text-align:left}.unit-value-table th{color:var(--muted);font-size:11px;text-transform:uppercase;letter-spacing:.06em}.unit-value-table td{font-weight:750}.unit-value-table tbody tr:last-child td{border-bottom:0}.unit-circle-tips{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:18px}
.riemann-formula-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin:22px 0}.tool-concept-figure{margin:28px 0 0}.tool-concept-figure img{display:block;width:100%;height:auto;border:1px solid var(--line);border-radius:20px;background:#080d16}.tool-concept-figure figcaption{margin-top:10px;color:var(--muted);font-size:13px}.riemann-check{display:grid;grid-template-columns:minmax(220px,.55fr) minmax(0,1fr);gap:24px;align-items:center;margin-top:18px;padding:22px}.riemann-check h3{margin:5px 0 0;font-size:24px}.riemann-check p{margin:0;color:var(--text-soft)}.tool-concept-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:22px}.tool-faq{margin-top:34px}.tool-faq h2{margin:7px 0 14px}.tool-faq details{border-top:1px solid var(--line);padding:15px 0}.tool-faq details:last-child{border-bottom:1px solid var(--line)}.tool-faq summary{cursor:pointer;font-weight:800}.tool-faq p{color:var(--text-soft)}
@media(max-width:900px){.tool-grid{grid-template-columns:1fr}.deep-dive-grid,.tool-explain,.riemann-formula-grid,.tool-cards-three{grid-template-columns:1fr}.riemann-controls,.tangent-controls{grid-template-columns:1fr 1fr}.related-tool{align-items:flex-start;flex-direction:column}.riemann-check{grid-template-columns:1fr}.tool-concept-links{grid-template-columns:1fr}.practice-toolbar{grid-template-columns:1fr auto}.practice-stats{grid-column:1/-1}.unit-practice-grid{grid-template-columns:1fr}.unit-circle-card{max-width:620px}.unit-circle-tips{grid-template-columns:1fr}}
@media(max-width:800px){.not-found-grid{grid-template-columns:1fr;gap:34px}.missing-plot{min-height:260px}.bio-brand{margin-bottom:52px}.tool-cards{grid-template-columns:1fr}}
@media(max-width:700px){.practice-page .page-hero{padding-top:34px;padding-bottom:28px}.practice-page .tool-hero-copy h1{font-size:clamp(38px,12vw,54px);line-height:.96}.practice-page .tool-hero-copy p{font-size:16px;line-height:1.55}.module-lessons .path-item{grid-template-columns:48px minmax(0,1fr)}.module-lessons .status{display:none}.module-outcome{padding:22px}.bio-shell{padding-top:24px}.bio-link{padding:14px}.bio-socials{display:grid;grid-template-columns:1fr 1fr}.bio-socials a:last-child{grid-column:1/-1}.not-found{padding:42px 0}.not-found h1{font-size:clamp(43px,13vw,66px)}.riemann-controls,.tangent-controls{grid-template-columns:1fr}.tool-panel{padding:14px}.tool-result>div{display:grid}.tool-result strong{text-align:left}.practice-toolbar{grid-template-columns:1fr}.practice-reset{justify-self:start}.practice-stats{grid-template-columns:1fr 1fr 1fr}.practice-stats div{padding:8px;border-left:0;border-top:1px solid var(--line)}.unit-circle-card,.practice-question-card{padding:14px}.practice-options{grid-template-columns:1fr}.practice-option{min-height:58px}}

/* module: 70-studio.css */
/* Educational animation commercial hub */
.studio-page{background:#070910}.studio-page .section{padding:76px 0}.studio-band{border-block:1px solid var(--line);background:rgba(255,255,255,.018)}
.studio-hero{padding:82px 0 70px;background:radial-gradient(circle at 14% 8%,rgba(86,184,255,.11),transparent 34%),radial-gradient(circle at 90% 4%,rgba(255,217,61,.07),transparent 28%)}
.studio-hero-grid{display:grid;grid-template-columns:minmax(0,1.55fr) minmax(300px,.55fr);gap:48px;align-items:end}.studio-hero h1{max-width:920px;margin:14px 0 20px;font-size:clamp(48px,6.6vw,92px);line-height:.94;letter-spacing:-.057em}.studio-lede{max-width:820px;margin:0;color:var(--text-soft);font-size:clamp(18px,2vw,23px);line-height:1.55}.studio-proofline{display:flex;flex-wrap:wrap;gap:8px;margin-top:30px}.studio-proofline span{padding:8px 11px;border:1px solid var(--line);border-radius:999px;color:var(--muted);font-size:11px;font-weight:850;letter-spacing:.05em;text-transform:uppercase}.studio-hero-note{padding:25px;border:1px solid var(--line-strong);border-radius:22px;background:linear-gradient(145deg,rgba(20,26,40,.96),rgba(9,12,20,.96));box-shadow:0 22px 62px rgba(0,0,0,.28)}.studio-hero-note strong{display:block;margin:9px 0 11px;font-size:25px;line-height:1.08}.studio-hero-note p{margin:0 0 18px;color:var(--text-soft)}.studio-hero-note a{color:var(--yellow);text-decoration:none;font-size:13px;font-weight:850}
.studio-page .section-head{display:flex;justify-content:space-between;gap:42px;align-items:end;margin-bottom:28px}.studio-page .section-head h2,.studio-split h2,.studio-delivery-grid h2,.studio-license h2,.studio-faq h2,.studio-quote h2{margin:8px 0 0;font-size:clamp(32px,4vw,54px);line-height:1;letter-spacing:-.045em}.studio-page .section-head>p{max-width:540px;margin:0;color:var(--text-soft)}
.studio-reel-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.studio-reel-card{overflow:hidden;border:1px solid var(--line);border-radius:20px;background:var(--surface-1)}.studio-reel-media{position:relative;aspect-ratio:16/10;overflow:hidden;background:#05070d}.studio-reel-media video{width:100%;height:100%;object-fit:cover;display:block}.studio-reel-media span{position:absolute;left:12px;top:12px;padding:6px 8px;border:1px solid rgba(255,255,255,.15);border-radius:999px;background:rgba(5,7,13,.7);backdrop-filter:blur(8px);font-size:10px;font-weight:900;letter-spacing:.08em;text-transform:uppercase}.studio-reel-copy{padding:18px}.studio-reel-copy h3{margin:0 0 7px;font-size:18px}.studio-reel-copy p{margin:0;color:var(--text-soft);font-size:14px;line-height:1.5}
.studio-card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.studio-card-grid article,.studio-audience article,.studio-why-grid article,.studio-license-grid article,.studio-pricing-grid article,.studio-cost-drivers article{padding:23px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1)}.studio-card-grid span,.studio-cost-drivers span{display:block;margin-bottom:24px;color:var(--yellow);font-size:11px;font-weight:900;letter-spacing:.12em}.studio-card-grid h3,.studio-audience h3,.studio-why-grid h3,.studio-license-grid h3,.studio-cost-drivers h3{margin:0 0 8px}.studio-card-grid p,.studio-audience p,.studio-why-grid p,.studio-license-grid p,.studio-cost-drivers p{margin:0;color:var(--text-soft)}
.studio-split{display:grid;grid-template-columns:minmax(0,.8fr) minmax(0,1.2fr);gap:56px}.studio-audience{display:grid;grid-template-columns:1fr 1fr;gap:14px}.studio-audience article{min-height:170px}
.studio-why-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.studio-why-grid article{padding:26px}.studio-why-mark{display:flex;align-items:center;justify-content:center;width:58px;height:58px;margin-bottom:28px;border:1px solid rgba(255,217,61,.34);border-radius:16px;background:rgba(255,217,61,.06);color:var(--yellow);font-size:18px;font-weight:900}.studio-why-grid h3{font-size:21px}
.studio-process{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin:0;padding:0;list-style:none}.studio-process li{display:flex;gap:15px;padding:22px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1)}.studio-process li>span{display:grid;place-items:center;flex:0 0 34px;width:34px;height:34px;border-radius:50%;background:var(--yellow);color:#090b10;font-weight:950}.studio-process h3{margin:2px 0 7px}.studio-process p{margin:0;color:var(--text-soft);font-size:14px}
.studio-delivery-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(330px,.72fr);gap:42px;align-items:start}.studio-checks{margin:25px 0 0;padding:0;list-style:none}.studio-checks li{position:relative;padding:12px 0 12px 27px;border-bottom:1px solid var(--line);color:var(--text-soft)}.studio-checks li:before{content:'✓';position:absolute;left:0;color:var(--mint);font-weight:900}.studio-price-card{padding:28px;border:1px solid rgba(255,217,61,.32);border-radius:22px;background:linear-gradient(150deg,rgba(255,217,61,.08),rgba(16,20,31,.9) 45%)}.studio-price-card h2{font-size:clamp(28px,3vw,42px)}.studio-price-card h2 strong{color:var(--yellow)}.studio-price-card p{color:var(--text-soft)}.studio-price-card small{display:block;margin-top:17px;color:var(--muted);line-height:1.5}.studio-price-card .text-link{display:inline-block;margin-top:8px;color:var(--yellow);font-weight:850;text-decoration:none}
.studio-license{display:grid;grid-template-columns:minmax(0,.6fr) minmax(0,1.4fr);gap:48px}.studio-license-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.studio-faq{max-width:930px}.studio-faq details{padding:18px 0;border-top:1px solid var(--line)}.studio-faq details:last-child{border-bottom:1px solid var(--line)}.studio-faq summary{cursor:pointer;font-weight:850;font-size:16px}.studio-faq p{max-width:780px;color:var(--text-soft)}
.studio-quote{background:radial-gradient(circle at 78% 10%,rgba(86,184,255,.08),transparent 30%)}.studio-quote-grid{display:grid;grid-template-columns:minmax(0,.72fr) minmax(0,1.28fr);gap:54px;align-items:start}.studio-quote-grid>div>p{color:var(--text-soft);font-size:17px;line-height:1.6}.studio-form{display:grid;grid-template-columns:1fr 1fr;gap:14px;padding:24px;border:1px solid var(--line-strong);border-radius:22px;background:var(--surface-1)}.studio-form label{display:grid;gap:7px;color:var(--text-soft);font-size:12px;font-weight:850;letter-spacing:.03em}.studio-form label span{color:var(--muted);font-weight:650}.studio-form input,.studio-form select{width:100%;min-height:48px;padding:11px 12px;border:1px solid var(--line-strong);border-radius:11px;background:#090d16;color:var(--text);font:inherit}.studio-form input:focus,.studio-form select:focus{outline:2px solid rgba(86,184,255,.35);outline-offset:1px}.studio-form-wide{grid-column:1/-1}.studio-form-submit{display:flex;align-items:center;gap:16px;margin-top:3px}.studio-form-submit p{margin:0;color:var(--muted);font-size:11px;line-height:1.45}.studio-form .feedback{min-height:22px;color:var(--mint);font-size:13px}
.studio-cost-hero{padding-bottom:58px}.studio-cost-hero .wrap{max-width:1000px}.studio-cost-hero h1{max-width:900px}.studio-pricing-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.studio-pricing-grid article{display:flex;flex-direction:column;min-height:330px}.studio-pricing-grid article.featured{border-color:rgba(255,217,61,.35);background:linear-gradient(145deg,rgba(255,217,61,.07),var(--surface-1) 45%)}.studio-pricing-grid h3{margin:10px 0 16px;color:var(--yellow);font-size:35px}.studio-pricing-grid p{color:var(--text-soft)}.studio-pricing-grid strong{margin-top:auto}.studio-cost-drivers{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:12px}.studio-cost-drivers article{padding:20px}.studio-cost-compare{display:grid;grid-template-columns:minmax(0,1fr) minmax(330px,.78fr);gap:42px;align-items:start}.studio-cost-compare h2{margin:8px 0 16px;font-size:clamp(34px,4vw,52px);letter-spacing:-.045em}.studio-cost-compare>div>p{color:var(--text-soft);font-size:18px}.studio-cost-compare aside{padding:24px;border:1px solid var(--line);border-radius:18px;background:var(--surface-1)}.studio-cost-compare aside strong{display:block;margin-top:14px}.studio-cost-compare aside strong:first-child{margin-top:0}.studio-cost-compare ul{padding-left:20px;color:var(--text-soft)}.studio-final-cta{display:flex;align-items:center;justify-content:space-between;gap:40px}.studio-final-cta p{max-width:680px;color:var(--text-soft)}.studio-final-cta .btn{flex:none}
@media(max-width:1080px){.studio-reel-grid,.studio-card-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.studio-process{grid-template-columns:1fr 1fr}.studio-cost-drivers{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:900px){.studio-hero-grid,.studio-split,.studio-delivery-grid,.studio-license,.studio-quote-grid,.studio-cost-compare{grid-template-columns:1fr}.studio-hero-note{max-width:620px}.studio-license-grid{grid-template-columns:1fr 1fr}.studio-why-grid,.studio-pricing-grid{grid-template-columns:1fr}.studio-pricing-grid article{min-height:0}.studio-page .section-head{align-items:flex-start;flex-direction:column}.studio-page .section-head>p{max-width:740px}.studio-final-cta{align-items:flex-start;flex-direction:column}}
@media(max-width:680px){.studio-page .section{padding:58px 0}.studio-hero{padding:58px 0 48px}.studio-hero h1{font-size:clamp(43px,13vw,64px)}.studio-reel-grid,.studio-card-grid,.studio-audience,.studio-process,.studio-license-grid,.studio-cost-drivers{grid-template-columns:1fr}.studio-reel-media{aspect-ratio:16/11}.studio-form{grid-template-columns:1fr;padding:17px}.studio-form label,.studio-form-wide{grid-column:1}.studio-form-submit{align-items:flex-start;flex-direction:column}.studio-proofline span{font-size:9px}.studio-final-cta .btn{width:100%;text-align:center}}