/* ============================================================
   MathNana — homepage
   Palette sampled from the logo: cream paper, navy ink, ochre.
   Type: Outfit (display, geometric — matches the logotype)
         Source Serif 4 (body & maths — how textbooks are set)
         IBM Plex Mono (labels, counts, marginal notes)
   ============================================================ */

:root{
  --paper:        #F9F1E4;
  --paper-raised: #FFFBF3;
  --paper-tint:   #F4EAD9;
  --ink:          #17305B;
  --ink-deep:     #0D1E3D;
  --ink-soft:     #4A5F84;
  --gold:         #B0812F;
  --gold-bright:  #C79A44;
  --gold-wash:    #EBDCBB;
  --rule:         rgba(23,48,91,.16);
  --rule-soft:    rgba(23,48,91,.09);

  /* Dark panels stay dark in BOTH themes — --ink-deep inverts to white in the
     dark palette, so it can only ever be a text colour, never a background. */
  --panel:        #0D1E3D;
  --panel-hover:  #132A52;
  --btn-bg:       #0D1E3D;
  --btn-bg-hover: #17305B;
  --btn-fg:       #FFFBF3;

  --shell: 1180px;
  --r: 4px;

  --display: "Outfit", ui-sans-serif, system-ui, sans-serif;
  --body: "Source Serif 4", Georgia, "Times New Roman", serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --ease: cubic-bezier(.22,.68,.32,1);
}

[data-theme="dark"]{
  --paper:        #0C1A31;
  --paper-raised: #12263F;
  --paper-tint:   #10203A;
  --ink:          #EFE6D5;
  --ink-deep:     #FFFFFF;
  --ink-soft:     #9FB0C9;
  --gold:         #D9A94F;
  --gold-bright:  #E8BE6C;
  --gold-wash:    #3A3320;
  --rule:         rgba(239,230,213,.18);
  --rule-soft:    rgba(239,230,213,.09);

  --panel:        #081527;
  --panel-hover:  #0E2039;
  --btn-bg:       #D9A94F;
  --btn-bg-hover: #E8BE6C;
  --btn-fg:       #0C1A31;
}

*,*::before,*::after{ box-sizing:border-box; }

html{ scroll-behavior:smooth; -webkit-text-size-adjust:100%; }

body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--body);
  font-size:17px;
  line-height:1.62;
  -webkit-font-smoothing:antialiased;
}

img{ max-width:100%; display:block; }
svg{ fill:none; stroke:currentColor; stroke-width:1.7; stroke-linecap:round; stroke-linejoin:round; }

a{ color:inherit; }

.shell{ width:100%; max-width:var(--shell); margin-inline:auto; padding-inline:28px; }

.skip{
  position:absolute; left:-9999px; top:0; z-index:100;
  background:var(--ink); color:var(--paper); padding:12px 20px;
  font-family:var(--mono); font-size:13px;
}
.skip:focus{ left:0; }

:focus-visible{ outline:2px solid var(--gold); outline-offset:3px; border-radius:2px; }

/* ── shared type ─────────────────────────────────────────── */

h1,h2,h3{
  font-family:var(--display);
  font-weight:500;
  letter-spacing:-.022em;
  line-height:1.08;
  margin:0;
  color:var(--ink-deep);
}

.eyebrow{
  font-family:var(--mono);
  font-size:11.5px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--gold);
  margin:0 0 14px;
}

/* the signature device: a marginal note stating the rule
   that governs the block it sits beside — as in a worked solution */
.sechead__why,
.sheet__note,
.step__why{
  font-family:var(--mono);
  font-size:11.5px;
  line-height:1.5;
  letter-spacing:.03em;
  color:var(--gold);
}

/* ── masthead ────────────────────────────────────────────── */

.masthead{
  position:sticky; top:0; z-index:60;
  background:color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter:saturate(1.4) blur(12px);
  border-bottom:1px solid var(--rule-soft);
}
.masthead__inner{
  display:flex; align-items:center; gap:28px;
  min-height:74px;
}

.brand{ display:flex; align-items:center; gap:12px; text-decoration:none; margin-right:auto; }

.brand__mark{
  width:44px; height:44px; flex:none;
  border-radius:50%;
  background-image:url("/logonew.jpg");
  background-size:264%;
  background-position:50% 41%;
  background-color:#F9F1E4;
  border:1px solid var(--rule);
}
[data-theme="dark"] .brand__mark{ border-color:rgba(239,230,213,.28); }

.brand__type{ display:flex; flex-direction:column; line-height:1; }
.brand__name{
  font-family:var(--display); font-weight:600; font-size:20px;
  letter-spacing:-.02em; color:var(--ink-deep);
}
.brand__tag{
  font-family:var(--mono); font-size:9.5px; letter-spacing:.15em;
  text-transform:uppercase; color:var(--gold); margin-top:5px;
}

.mainnav{ display:flex; gap:30px; }
.mainnav a{
  font-family:var(--display); font-size:15px; font-weight:400;
  text-decoration:none; color:var(--ink); padding:4px 0;
  border-bottom:1px solid transparent;
  transition:border-color .2s var(--ease), color .2s var(--ease);
}
.mainnav a:hover{ color:var(--gold); border-bottom-color:var(--gold); }

.theme{
  width:38px; height:38px; flex:none;
  display:grid; place-items:center;
  background:none; border:1px solid var(--rule); border-radius:50%;
  color:var(--ink); cursor:pointer;
  transition:border-color .2s var(--ease), color .2s var(--ease);
}
.theme:hover{ color:var(--gold); border-color:var(--gold); }
.theme svg{ width:17px; height:17px; }

.burger{
  display:none; width:38px; height:38px;
  flex-direction:column; justify-content:center; align-items:center; gap:5px;
  background:none; border:1px solid var(--rule); border-radius:50%;
  cursor:pointer; padding:0;
}
.burger span{ width:15px; height:1.5px; background:var(--ink); transition:transform .25s var(--ease); }
.burger[aria-expanded="true"] span:first-child{ transform:translateY(3.2px) rotate(45deg); }
.burger[aria-expanded="true"] span:last-child{ transform:translateY(-3.2px) rotate(-45deg); }

/* ── hero ────────────────────────────────────────────────── */

.hero{ padding:78px 0 84px; }

.hero__grid{
  display:grid;
  grid-template-columns:minmax(0,1.02fr) minmax(0,.98fr);
  gap:72px; align-items:start;
}

.hero h1{
  font-size:clamp(2.6rem, 5.4vw, 4.15rem);
  font-weight:300;
  letter-spacing:-.035em;
}
.hero h1 em{
  font-family:var(--body);
  font-style:italic;
  font-weight:400;
  color:var(--gold);
  letter-spacing:-.01em;
}

.hero__sub{
  max-width:44ch;
  margin:26px 0 34px;
  font-size:18.5px;
  color:var(--ink-soft);
}

.hero__meta{
  display:flex; gap:26px; flex-wrap:wrap;
  margin:26px 0 0;
  font-family:var(--mono); font-size:12px; letter-spacing:.04em;
  color:var(--ink-soft);
}
.hero__meta strong{ color:var(--ink-deep); font-weight:500; }

/* finder */
.finder{ position:relative; max-width:470px; }
.finder__label{
  display:block;
  font-family:var(--mono); font-size:11px; letter-spacing:.14em;
  text-transform:uppercase; color:var(--ink-soft); margin-bottom:9px;
}
.finder__field{
  display:flex; align-items:center; gap:11px;
  background:var(--paper-raised);
  border:1px solid var(--rule);
  border-radius:var(--r);
  padding:0 14px;
  transition:border-color .2s var(--ease), box-shadow .2s var(--ease);
}
.finder__field:focus-within{
  border-color:var(--gold);
  box-shadow:0 0 0 3px var(--gold-wash);
}
.finder__icon{ width:18px; height:18px; flex:none; color:var(--ink-soft); }
.finder__field input{
  flex:1; min-width:0;
  border:0; background:none; outline:none;
  font-family:var(--body); font-size:17px; color:var(--ink);
  padding:15px 0;
}
.finder__field input::placeholder{ color:var(--ink-soft); opacity:.72; }
.finder__kbd{
  font-family:var(--mono); font-size:11px; color:var(--ink-soft);
  border:1px solid var(--rule); border-radius:3px;
  padding:2px 6px; flex:none;
}

.results{
  position:absolute; z-index:40; left:0; right:0; top:calc(100% + 7px);
  margin:0; padding:6px; list-style:none;
  max-height:322px; overflow-y:auto;
  background:var(--paper-raised);
  border:1px solid var(--rule); border-radius:var(--r);
  box-shadow:0 18px 44px -18px rgba(13,30,61,.34);
}
.results li{ border-radius:3px; }
.results a{
  display:flex; align-items:baseline; gap:10px;
  padding:9px 12px; text-decoration:none;
  font-family:var(--display); font-size:15px;
}
.results a small{
  margin-left:auto;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.1em;
  text-transform:uppercase; color:var(--ink-soft);
}
.results li[aria-selected="true"] a,
.results a:hover{ background:var(--paper-tint); }
.results li[aria-selected="true"] a small,
.results a:hover small{ color:var(--gold); }
.results__empty{
  padding:14px 12px; font-size:15px; color:var(--ink-soft);
}

/* ── the solution sheet (signature) ──────────────────────── */

.sheet{
  margin:0;
  background:var(--paper-raised);
  border:1px solid var(--rule);
  border-radius:var(--r);
  padding:26px 28px 20px;
  box-shadow:0 24px 60px -34px rgba(13,30,61,.4);
}

.sheet__head{
  display:flex; align-items:baseline; justify-content:space-between; gap:16px;
  padding-bottom:16px; border-bottom:1px solid var(--rule-soft);
}
.sheet__title{
  font-family:var(--display); font-weight:500; font-size:15.5px;
  color:var(--ink-deep);
}

.steps{ list-style:none; margin:0; padding:22px 0 6px; }

.step{
  position:relative;
  display:grid;
  grid-template-columns:minmax(0,1fr) 150px;
  gap:20px; align-items:baseline;
  padding:13px 0 13px 26px;
  opacity:0;
  transform:translateY(7px);
}
.step.is-in{
  opacity:1; transform:none;
  transition:opacity .5s var(--ease), transform .5s var(--ease);
}

/* the working rule: a hairline down the left, as in a solution column */
.step::before{
  content:"";
  position:absolute; left:0; top:0; bottom:0;
  width:1px; background:var(--rule);
}
.step::after{
  content:attr(data-step);
  position:absolute; left:-13px; top:14px;
  width:20px; height:20px; border-radius:50%;
  display:grid; place-items:center;
  background:var(--paper-raised);
  border:1px solid var(--rule);
  font-family:var(--mono); font-size:10px; color:var(--ink-soft);
}

.step__math{
  font-family:var(--body);
  font-size:clamp(19px, 2.1vw, 23px);
  line-height:1.3;
  color:var(--ink-deep);
  font-variant-numeric:lining-nums;
}
.step__math i{ font-style:italic; }

.step--final .step__math{
  color:var(--gold);
  font-weight:600;
}
.step--final::after{ border-color:var(--gold); color:var(--gold); }

.sheet__foot{
  display:flex; align-items:center; justify-content:space-between;
  gap:16px; flex-wrap:wrap;
  margin-top:16px; padding-top:15px;
  border-top:1px solid var(--rule-soft);
}
.replay{
  display:inline-flex; align-items:center; gap:8px;
  background:none; border:0; padding:0; cursor:pointer;
  font-family:var(--mono); font-size:11.5px; letter-spacing:.06em;
  color:var(--ink-soft);
  transition:color .2s var(--ease);
}
.replay:hover{ color:var(--gold); }
.replay svg{ width:14px; height:14px; }

.verified{
  font-family:var(--mono); font-size:11px; letter-spacing:.04em;
  color:var(--ink-soft);
  display:inline-flex; align-items:center; gap:7px;
}
.verified::before{
  content:""; width:6px; height:6px; border-radius:50%;
  background:var(--gold);
}

/* ── sections ────────────────────────────────────────────── */

.section{ padding:88px 0; border-top:1px solid var(--rule-soft); }
.section--tint{ background:var(--paper-tint); }
.section--ink{ background:var(--panel); color:#EFE6D5; border-top:0; }
.section--ink h2{ color:#FFFBF3; }
.section--ink .eyebrow,
.section--ink .sechead__why{ color:var(--gold-bright); }

.sechead{
  display:flex; align-items:flex-end; justify-content:space-between;
  gap:40px; margin-bottom:48px;
  padding-bottom:20px; border-bottom:1px solid var(--rule);
}
.section--ink .sechead{ border-bottom-color:rgba(239,230,213,.2); }
.sechead h2{ font-size:clamp(1.75rem, 3.1vw, 2.5rem); }
.sechead__why{ max-width:24ch; text-align:right; flex:none; margin:0; }

/* ── category grid ───────────────────────────────────────── */

.cats{
  display:grid;
  grid-template-columns:repeat(3, minmax(0,1fr));
  gap:1px;
  background:var(--rule);
  border:1px solid var(--rule);
}

.cat{
  position:relative;
  display:flex; flex-direction:column;
  gap:10px;
  padding:30px 28px 26px;
  background:var(--paper);
  text-decoration:none;
  transition:background .22s var(--ease);
}
.cat:hover{ background:var(--paper-raised); }

/* gold rule that draws in on hover — the only hover flourish */
.cat::after{
  content:""; position:absolute; left:0; right:0; bottom:0; height:2px;
  background:var(--gold);
  transform:scaleX(0); transform-origin:left;
  transition:transform .34s var(--ease);
}
.cat:hover::after,
.cat:focus-within::after{ transform:scaleX(1); }

.cat--wide{ grid-column:span 2; }

.cat__icon{ color:var(--gold); }
.cat__icon svg{ width:26px; height:26px; }

.cat h3{ font-size:21px; font-weight:500; }
.cat--wide h3{ font-size:26px; }
.cat__title{
  text-decoration:none;
  transition:color .18s var(--ease);
}
.cat__title::after{ content:""; position:absolute; inset:0; }
.cat:hover .cat__title{ color:var(--gold); }

.cat__desc{
  margin:0;
  font-size:15.5px; line-height:1.55;
  color:var(--ink-soft);
  max-width:38ch;
}

.cat__links{
  position:relative; z-index:1;
  list-style:none; margin:8px 0 0; padding:0;
  display:flex; flex-wrap:wrap; gap:6px 8px;
}
.cat__links a{
  display:inline-block;
  font-family:var(--mono); font-size:11.5px; letter-spacing:.02em;
  text-decoration:none;
  color:var(--ink-soft);
  border:1px solid var(--rule-soft);
  border-radius:2px;
  padding:4px 8px;
  transition:color .18s var(--ease), border-color .18s var(--ease);
}
.cat__links a:hover{ color:var(--gold); border-color:var(--gold); }

.cat__count{
  margin-top:auto; padding-top:16px;
  font-family:var(--mono); font-size:11px; letter-spacing:.1em;
  text-transform:uppercase; color:var(--gold);
}

/* ── three questions ─────────────────────────────────────── */

.asks{
  display:grid; grid-template-columns:repeat(3, minmax(0,1fr));
  gap:1px; background:rgba(239,230,213,.2);
  border:1px solid rgba(239,230,213,.2);
}
.ask{ background:var(--panel); padding:34px 30px 32px; display:flex; flex-direction:column; }

.ask__q{
  font-family:var(--display);
  font-size:20px; font-weight:400; letter-spacing:-.02em;
  color:#FFFBF3;
  margin:0 0 16px;
}
.ask__a{
  margin:0 0 22px;
  font-size:16px; line-height:1.6;
  color:rgba(239,230,213,.76);
}

.ask__link{
  margin-top:auto;
  font-family:var(--mono); font-size:11.5px; letter-spacing:.08em;
  text-transform:uppercase; text-decoration:none;
  color:var(--gold-bright);
  border-bottom:1px solid rgba(217,169,79,.35);
  padding-bottom:3px;
  align-self:flex-start;
  transition:border-color .2s var(--ease);
}
.ask__link:hover{ border-bottom-color:var(--gold-bright); }

/* ── prerequisite chain ──────────────────────────────────── */

.chain{
  display:flex; align-items:center; gap:20px;
  padding:22px 24px; margin-bottom:34px;
  border:1px solid var(--rule); border-radius:var(--r);
  background:var(--paper-raised);
  overflow-x:auto;
}
.chain__label{
  flex:none;
  font-family:var(--mono); font-size:11px; letter-spacing:.12em;
  text-transform:uppercase; color:var(--gold);
}
.chain__list{
  display:flex; align-items:center; gap:14px;
  list-style:none; margin:0; padding:0;
}
.chain__list li{ display:flex; align-items:center; gap:14px; flex:none; }
.chain__list li:not(:last-child)::after{
  content:""; width:22px; height:1px; background:var(--rule);
  position:relative;
}
.chain__list a{
  font-family:var(--display); font-size:14px; text-decoration:none;
  white-space:nowrap;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease), border-color .18s var(--ease);
}
.chain__list a:hover{ color:var(--gold); border-bottom-color:var(--gold); }

.paths{
  display:grid; grid-template-columns:repeat(3, minmax(0,1fr));
  gap:14px;
}
.path{
  display:flex; flex-direction:column; gap:6px;
  padding:20px 22px;
  border:1px solid var(--rule); border-radius:var(--r);
  text-decoration:none;
  transition:border-color .2s var(--ease), background .2s var(--ease);
}
.path:hover{ border-color:var(--gold); background:var(--paper-raised); }
.path span{ font-family:var(--display); font-size:17px; color:var(--ink-deep); }
.path em{
  font-family:var(--mono); font-size:11px; font-style:normal;
  letter-spacing:.05em; color:var(--ink-soft);
}
.path--test{
  grid-column:span 3;
  background:var(--panel);
  border-color:var(--panel);
  flex-direction:row; align-items:center; justify-content:space-between;
}
.path--test:hover{ background:var(--panel-hover); border-color:var(--panel-hover); }
.path--test span{ color:#FFFBF3; }
.path--test em{ color:var(--gold-bright); }

/* ── popular list ────────────────────────────────────────── */

.popular{
  list-style:none; margin:0; padding:0;
  columns:2; column-gap:56px;
}
.popular li{ break-inside:avoid; }
.popular a{
  display:flex; align-items:baseline; gap:14px;
  padding:12px 0;
  border-bottom:1px solid var(--rule-soft);
  text-decoration:none;
  transition:color .18s var(--ease);
}
.popular a:hover{ color:var(--gold); }
.popular .p__name{ font-family:var(--display); font-size:16px; }
.popular .p__branch{
  margin-left:auto; flex:none;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.1em;
  text-transform:uppercase; color:var(--ink-soft);
}

/* ── verify strip ────────────────────────────────────────── */

.verify{ padding:76px 0; border-top:1px solid var(--rule-soft); }
.verify__inner{ display:grid; grid-template-columns:120px minmax(0,1fr); gap:44px; align-items:start; }
.verify__mark{
  width:120px; height:120px; border-radius:50%;
  background-image:url("/logonew.jpg");
  background-size:264%; background-position:50% 41%;
  background-color:#F9F1E4;
  border:1px solid var(--rule);
}
[data-theme="dark"] .verify__mark{ border-color:rgba(239,230,213,.28); }
.verify h2{ font-size:clamp(1.5rem,2.6vw,2rem); margin-bottom:16px; }
.verify p{ margin:0 0 14px; max-width:62ch; color:var(--ink-soft); font-size:16.5px; }
.verify__links{ display:flex; gap:26px; flex-wrap:wrap; }
.verify__links a{
  font-family:var(--mono); font-size:11.5px; letter-spacing:.08em;
  text-transform:uppercase; text-decoration:none; color:var(--gold);
  border-bottom:1px solid var(--gold-wash); padding-bottom:3px;
  transition:border-color .2s var(--ease);
}
.verify__links a:hover{ border-bottom-color:var(--gold); }

/* ── footer ──────────────────────────────────────────────── */

.foot{
  background:var(--panel); color:rgba(239,230,213,.8);
  padding:64px 0 28px;
}
.foot__grid{
  display:grid;
  grid-template-columns:1.6fr repeat(5, 1fr);
  gap:36px;
  padding-bottom:44px;
  border-bottom:1px solid rgba(239,230,213,.16);
}
.brand__mark--lg{ width:52px; height:52px; display:block; }
.foot__tag{
  font-family:var(--mono); font-size:10px; letter-spacing:.15em;
  text-transform:uppercase; color:var(--gold-bright);
  margin:16px 0 12px;
}
.foot__blurb{ margin:0; font-size:14.5px; line-height:1.6; max-width:30ch; color:rgba(239,230,213,.6); }

.foot__col{ display:flex; flex-direction:column; gap:9px; }
.foot__col h3{
  font-family:var(--mono); font-size:10.5px; letter-spacing:.14em;
  text-transform:uppercase; font-weight:500;
  color:var(--gold-bright); margin:0 0 6px;
}
.foot__col a{
  font-family:var(--display); font-size:14px; text-decoration:none;
  color:rgba(239,230,213,.78);
  transition:color .18s var(--ease);
}
.foot__col a:hover{ color:var(--gold-bright); }

.foot__legal{
  display:flex; gap:26px; flex-wrap:wrap;
  margin:22px 0 0;
  font-family:var(--mono); font-size:11px; letter-spacing:.05em;
  color:rgba(239,230,213,.5);
}
.foot__legal a{ text-decoration:none; }
.foot__legal a:hover{ color:var(--gold-bright); }

/* ── scroll reveal ───────────────────────────────────────── */

.reveal{ opacity:0; transform:translateY(14px); }
.reveal.is-in{
  opacity:1; transform:none;
  transition:opacity .6s var(--ease), transform .6s var(--ease);
}

/* ── responsive ──────────────────────────────────────────── */

@media (max-width:1080px){
  .hero__grid{ grid-template-columns:1fr; gap:52px; }
  .sheet{ max-width:640px; }
  .foot__grid{ grid-template-columns:1fr 1fr 1fr; }
  .foot__brand{ grid-column:span 3; }
}

@media (max-width:860px){
  .cats{ grid-template-columns:repeat(2, minmax(0,1fr)); }
  .cat--wide{ grid-column:span 2; }
  .asks{ grid-template-columns:1fr; }
  .paths{ grid-template-columns:1fr 1fr; }
  .path--test{ grid-column:span 2; }
  .popular{ columns:1; }
  .sechead{ flex-direction:column; align-items:flex-start; gap:14px; }
  .sechead__why{ text-align:left; max-width:40ch; }
}

@media (max-width:720px){
  body{ font-size:16px; }
  .shell{ padding-inline:20px; }
  .mainnav{
    position:absolute; top:100%; left:0; right:0;
    flex-direction:column; gap:0;
    background:var(--paper-raised);
    border-bottom:1px solid var(--rule);
    padding:8px 20px 18px;
    display:none;
  }
  .mainnav.is-open{ display:flex; }
  .mainnav a{ padding:12px 0; border-bottom:1px solid var(--rule-soft); }
  .burger{ display:flex; }
  .hero{ padding:52px 0 60px; }
  .section{ padding:62px 0; }
  .verify{ padding:56px 0; }
  .verify__inner{ grid-template-columns:1fr; gap:26px; }
  .step{ grid-template-columns:1fr; gap:7px; }
  .step__why{ padding-left:0; }
  .sheet{ padding:22px 20px 18px; }
  .cats{ grid-template-columns:1fr; }
  .cat--wide{ grid-column:span 1; }
  .paths{ grid-template-columns:1fr; }
  .path--test{ grid-column:span 1; flex-direction:column; align-items:flex-start; }
  .foot__grid{ grid-template-columns:1fr 1fr; }
  .foot__brand{ grid-column:span 2; }
}

@media (prefers-reduced-motion:reduce){
  html{ scroll-behavior:auto; }
  *,*::before,*::after{
    animation-duration:.001ms !important;
    transition-duration:.001ms !important;
  }
  .step,.reveal{ opacity:1; transform:none; }
}

/* ============================================================
   CATEGORY HUB PAGES  (/algebra/, /fractions/, …)
   Generated by build.py — same tokens, same signature device.
   ============================================================ */

/* ── breadcrumb + hub header ─────────────────────────────── */

.crumb{
  display:flex; align-items:center; gap:10px;
  font-family:var(--mono); font-size:11px; letter-spacing:.08em;
  text-transform:uppercase; color:var(--ink-soft);
  margin-bottom:34px;
}
.crumb a{ text-decoration:none; }
.crumb a:hover{ color:var(--gold); }
.crumb span[aria-hidden]{ color:var(--rule); }
.crumb [aria-current]{ color:var(--gold); }

.hubhead{ padding:40px 0 74px; }

.hubhead__grid{
  display:grid;
  grid-template-columns:minmax(0,1fr) minmax(0,.86fr);
  gap:68px; align-items:start;
}

.hubhead h1{
  font-size:clamp(2.5rem, 5vw, 3.9rem);
  font-weight:300;
  letter-spacing:-.035em;
}

.hubhead__lede{
  max-width:46ch;
  margin:22px 0 26px;
  font-size:18.5px;
  color:var(--ink-soft);
}

.verified--block{
  display:inline-flex;
  margin:0;
  padding-top:16px;
  border-top:1px solid var(--rule-soft);
}

/* ── calculator clusters ─────────────────────────────────── */

.cluster{ margin-bottom:50px; }
.cluster:last-child{ margin-bottom:0; }

.cluster__name{
  font-family:var(--mono); font-size:11px; font-weight:500;
  letter-spacing:.16em; text-transform:uppercase;
  color:var(--gold);
  margin:0 0 4px;
  padding-bottom:12px;
  border-bottom:1px solid var(--rule);
}

.calcs{
  list-style:none; margin:0; padding:0;
  display:grid; grid-template-columns:repeat(2, minmax(0,1fr));
  gap:0 46px;
}
.calcs li{ border-bottom:1px solid var(--rule-soft); }

.calcs a{
  display:grid;
  grid-template-columns:minmax(0,15em) minmax(0,1fr);
  gap:20px; align-items:baseline;
  padding:15px 0;
  text-decoration:none;
  transition:color .18s var(--ease);
}
.calcs a:hover{ color:var(--gold); }

.calc__name{ font-family:var(--display); font-size:16.5px; color:var(--ink-deep); }
.calcs a:hover .calc__name{ color:var(--gold); }
.calc__desc{ font-size:14.5px; line-height:1.5; color:var(--ink-soft); }

/* ── prerequisite hint ───────────────────────────────────── */

.chain__hint{
  margin:18px 0 0;
  max-width:64ch;
  font-size:15.5px;
  color:var(--ink-soft);
}

/* ── knowledge-base cards ────────────────────────────────── */

.kbcards{
  display:grid; grid-template-columns:repeat(3, minmax(0,1fr));
  gap:1px;
  background:rgba(239,230,213,.2);
  border:1px solid rgba(239,230,213,.2);
}
.kbcard{
  display:flex; flex-direction:column; gap:12px;
  padding:26px 24px 28px;
  background:var(--panel);
  text-decoration:none;
  transition:background .2s var(--ease);
}
.kbcard:hover{ background:var(--panel-hover); }
.kbcard__type{
  font-family:var(--mono); font-size:10px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold-bright);
}
.kbcard__title{
  font-family:var(--display); font-size:18px; line-height:1.28;
  letter-spacing:-.015em; color:#FFFBF3;
}

.kbmore{ margin:26px 0 0; }
.kbmore a{
  font-family:var(--mono); font-size:11.5px; letter-spacing:.08em;
  text-transform:uppercase; text-decoration:none;
  color:var(--gold-bright);
  border-bottom:1px solid rgba(217,169,79,.35);
  padding-bottom:3px;
}
.kbmore a:hover{ border-bottom-color:var(--gold-bright); }

/* ── FAQ ─────────────────────────────────────────────────── */

.faq{ max-width:78ch; }

.qa{ border-bottom:1px solid var(--rule); }
.qa summary{
  display:flex; align-items:baseline; gap:16px;
  padding:22px 0;
  cursor:pointer; list-style:none;
  font-family:var(--display); font-size:19px;
  letter-spacing:-.015em; color:var(--ink-deep);
  transition:color .18s var(--ease);
}
.qa summary::-webkit-details-marker{ display:none; }
.qa summary:hover{ color:var(--gold); }
.qa summary::after{
  content:"+";
  margin-left:auto; flex:none;
  font-family:var(--mono); font-size:19px; font-weight:400;
  color:var(--gold);
  transition:transform .25s var(--ease);
}
.qa[open] summary::after{ transform:rotate(45deg); }
.qa p{
  margin:0; padding:0 0 24px;
  max-width:64ch;
  font-size:16.5px; color:var(--ink-soft);
}

/* ── responsive ──────────────────────────────────────────── */

@media (max-width:1080px){
  .hubhead__grid{ grid-template-columns:1fr; gap:46px; }
  .hubhead .sheet{ max-width:640px; }
}

@media (max-width:860px){
  .calcs{ grid-template-columns:1fr; gap:0; }
  .kbcards{ grid-template-columns:repeat(2, minmax(0,1fr)); }
}

@media (max-width:720px){
  .hubhead{ padding:28px 0 52px; }
  .calcs a{ grid-template-columns:1fr; gap:4px; padding:13px 0; }
  .kbcards{ grid-template-columns:1fr; }
  .qa summary{ font-size:17.5px; }
}

/* ============================================================
   CALCULATOR PAGES
   The output is the same annotated solution sheet used in every
   hero — the tool and the worked example are one component.
   ============================================================ */

.hubhead--calc{ padding-bottom:38px; }
.hubhead--calc h1{ font-size:clamp(2.2rem, 4.2vw, 3.2rem); }
.hubhead--calc .hubhead__lede{ max-width:60ch; margin-bottom:0; }

.toolwrap{ padding:0 0 74px; }

.tool{
  display:grid;
  grid-template-columns:minmax(0,360px) minmax(0,1fr);
  gap:28px; align-items:start;
}

.tool__inputs{
  display:flex; flex-direction:column; gap:18px;
  padding:26px 24px;
  background:var(--paper-raised);
  border:1px solid var(--rule);
  border-radius:var(--r);
}

.field{ display:flex; flex-direction:column; gap:7px; }
.field label{
  font-family:var(--mono); font-size:11px; letter-spacing:.13em;
  text-transform:uppercase; color:var(--ink-soft);
}
.field input,
.field select,
.field textarea{
  width:100%;
  font-family:var(--body); font-size:17px; color:var(--ink);
  background:var(--paper);
  border:1px solid var(--rule); border-radius:3px;
  padding:11px 12px;
  transition:border-color .18s var(--ease), box-shadow .18s var(--ease);
}
.field textarea{ resize:vertical; line-height:1.5; }
.field select{
  font-family:var(--display); font-size:15px;
  appearance:none;
  background-image:linear-gradient(45deg,transparent 50%,currentColor 50%),
                   linear-gradient(135deg,currentColor 50%,transparent 50%);
  background-position:calc(100% - 17px) 50%, calc(100% - 12px) 50%;
  background-size:5px 5px, 5px 5px;
  background-repeat:no-repeat;
  padding-right:34px;
}
.field input:focus,
.field select:focus,
.field textarea:focus{
  outline:none;
  border-color:var(--gold);
  box-shadow:0 0 0 3px var(--gold-wash);
}
.field__hint{ font-size:13.5px; line-height:1.45; color:var(--ink-soft); }

.fgroup{
  display:grid; grid-template-columns:1fr 1fr; gap:12px;
  margin:0; padding:14px 14px 16px;
  border:1px solid var(--rule-soft); border-radius:3px;
}
.fgroup legend{
  padding:0 7px;
  font-family:var(--mono); font-size:10px; letter-spacing:.14em;
  text-transform:uppercase; color:var(--gold);
}

.tool__actions{ display:flex; gap:10px; flex-wrap:wrap; margin-top:4px; }

.btn{
  font-family:var(--display); font-size:15px; font-weight:500;
  padding:12px 22px; cursor:pointer;
  background:var(--btn-bg); color:var(--btn-fg);
  border:1px solid var(--btn-bg); border-radius:3px;
  transition:background .18s var(--ease), border-color .18s var(--ease);
}
.btn:hover{ background:var(--btn-bg-hover); border-color:var(--btn-bg-hover); }
.btn--ghost{
  background:none; color:var(--ink);
  border-color:var(--rule);
}
.btn--ghost:hover{ background:none; color:var(--gold); border-color:var(--gold); }

.tool__out{ margin:0; min-height:230px; }
.tool__out.is-error{ border-color:rgba(176,129,47,.5); }

.tool__error,
.tool__note,
.tool__extra{ list-style:none; }

.tool__error{
  padding:26px 0 8px;
  font-size:17px; color:var(--gold);
  max-width:52ch;
}
.tool__note{
  margin-top:14px; padding:14px 16px;
  background:var(--paper-tint); border-radius:3px;
  font-size:15.5px; line-height:1.55; color:var(--ink-soft);
  max-width:62ch;
}
.tool__extra{
  display:flex; flex-wrap:wrap; gap:8px 10px;
  margin-top:18px; padding-top:16px;
  border-top:1px solid var(--rule-soft);
}
.tool__extra span{
  font-family:var(--mono); font-size:11.5px; letter-spacing:.02em;
  color:var(--ink-soft);
  border:1px solid var(--rule-soft); border-radius:2px;
  padding:5px 9px;
}

/* Stacked fractions in the working. The slash is kept in the markup so the
   value still reads correctly when copied or announced, but it is not drawn —
   the rule under the numerator is the visible bar. */
.frac{
  display:inline-flex; flex-direction:column; align-items:center;
  vertical-align:-0.34em; line-height:1.12; margin:0 .16em;
}
.frac sup,
.frac sub{ font-size:.64em; position:static; padding:0 .2em; }
.frac sup{ border-bottom:1px solid currentColor; padding-bottom:.08em; }
.frac sub{ padding-top:.08em; }
.frac__slash{
  position:absolute; width:1px; height:1px;
  overflow:hidden; clip-path:inset(50%); white-space:nowrap;
}

/* ── prose, mistakes ─────────────────────────────────────── */

.proses{ display:grid; grid-template-columns:repeat(2, minmax(0,1fr)); gap:44px; }
.prose h3{ font-size:20px; font-weight:500; margin-bottom:12px; }
.prose p{ margin:0; font-size:16.5px; color:var(--ink-soft); max-width:52ch; }

.mistakes{
  counter-reset:mis;
  list-style:none; margin:0; padding:0;
  display:grid; grid-template-columns:repeat(3, minmax(0,1fr)); gap:1px;
  background:rgba(239,230,213,.2);
  border:1px solid rgba(239,230,213,.2);
}
.mistakes li{
  position:relative;
  background:var(--panel);
  padding:30px 26px 30px;
}
.mistakes li::before{
  counter-increment:mis; content:counter(mis);
  font-family:var(--mono); font-size:10.5px; letter-spacing:.1em;
  color:var(--gold-bright);
}
.mistakes h3{
  font-size:19px; font-weight:400; letter-spacing:-.015em;
  color:#FFFBF3; margin:10px 0 12px;
}
.mistakes p{ margin:0; font-size:15.5px; line-height:1.6; color:rgba(239,230,213,.76); }

/* ── responsive ──────────────────────────────────────────── */

@media (max-width:1080px){
  .tool{ grid-template-columns:1fr; }
  .tool__inputs{ max-width:520px; }
  .mistakes{ grid-template-columns:1fr; }
}

@media (max-width:860px){
  .proses{ grid-template-columns:1fr; gap:32px; }
}

@media (max-width:720px){
  .toolwrap{ padding-bottom:52px; }
  .tool__inputs{ max-width:none; padding:20px 18px; }
  .btn{ flex:1; }
}

/* A calculator that is planned but not built yet is listed, not linked —
   the site never ships an internal link to a page that would 404. */
.soon{ color:var(--ink-soft); opacity:.62; cursor:default; }
.calcs .soon{ display:grid; grid-template-columns:minmax(0,15em) minmax(0,1fr);
              gap:20px; align-items:baseline; padding:15px 0; }
.calcs .soon .calc__name{ color:var(--ink-soft); }
.cat__links .soon{ display:inline-block; border:1px dashed var(--rule-soft);
                   border-radius:2px; padding:4px 8px; font-family:var(--mono);
                   font-size:11.5px; }
.foot .soon{ font-family:var(--display); font-size:14px; color:rgba(239,230,213,.42); }
.chain__list .soon{ font-family:var(--display); font-size:14px; white-space:nowrap; }
.path.soon{ opacity:.5; }
.proses--single{ grid-template-columns:1fr; gap:34px; max-width:70ch; }
.proses--single .prose p{ max-width:none; }

/* ============================================================
   KNOWLEDGE BASE — blog index and article layout
   A reading column, not a tool layout: narrow measure, larger
   type, and the solution sheet reused inline for worked examples.
   ============================================================ */

.shell--reading{ max-width:960px; }

/* ── article cards (index and related) ───────────────────── */

/* auto-fill rather than a fixed three, so a branch with one article does not
   leave two empty cells sitting in the grid */
.acards{
  display:grid;
  grid-template-columns:repeat(auto-fill, minmax(290px, 1fr));
  gap:16px;
}
.acard{
  display:flex; flex-direction:column; gap:11px;
  padding:24px 24px 22px;
  background:var(--paper-raised); text-decoration:none;
  border:1px solid var(--rule); border-radius:var(--r);
  transition:border-color .2s var(--ease), background .2s var(--ease);
}
.acard:hover{ border-color:var(--gold); background:var(--paper); }
.acard__type{
  font-family:var(--mono); font-size:10px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold);
}
.acard__type em{
  font-style:normal; color:var(--ink-soft);
}
.acard__type em::before{ content:"·"; margin:0 .5em; }
.acard__title{
  font-family:var(--display); font-size:19px; font-weight:500;
  line-height:1.25; letter-spacing:-.018em; color:var(--ink-deep);
}
.acard:hover .acard__title{ color:var(--gold); }
.acard__excerpt{ font-size:15px; line-height:1.55; color:var(--ink-soft); }
.acard__meta{
  margin-top:auto; padding-top:14px;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.08em;
  text-transform:uppercase; color:var(--ink-soft);
}

.kbmore--light a{ color:var(--gold); border-bottom-color:var(--gold-wash); }

/* ── article page ────────────────────────────────────────── */

.art__head{ padding:40px 0 34px; border-bottom:1px solid var(--rule); }
.art__type{
  font-family:var(--mono); font-size:11px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold); margin:0 0 16px;
}
.art h1{
  font-size:clamp(2.1rem, 4.4vw, 3.1rem);
  font-weight:300; letter-spacing:-.032em; max-width:20ch;
}
.art__dek{
  margin:20px 0 24px; max-width:52ch;
  font-size:20px; line-height:1.5; color:var(--ink-soft);
}
.art__meta{
  display:flex; gap:22px; flex-wrap:wrap; margin:0;
  font-family:var(--mono); font-size:11px; letter-spacing:.05em;
  color:var(--ink-soft);
}

.art__grid{
  display:grid; grid-template-columns:200px minmax(0,1fr);
  gap:56px; align-items:start;
  padding:44px 0 66px;
}

.toc{ position:sticky; top:100px; }
.toc__label{
  font-family:var(--mono); font-size:10px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold); margin:0 0 14px;
}
.toc ol{ list-style:none; margin:0; padding:0; counter-reset:toc; }
.toc li{ margin-bottom:11px; }
.toc a{
  font-family:var(--display); font-size:13.5px; line-height:1.35;
  text-decoration:none; color:var(--ink-soft);
  display:block; padding-left:14px; border-left:1px solid var(--rule);
  transition:color .18s var(--ease), border-color .18s var(--ease);
}
.toc a:hover{ color:var(--gold); border-left-color:var(--gold); }
.toc__cta{
  display:inline-block; margin-top:22px;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.08em;
  text-transform:uppercase; text-decoration:none; color:var(--gold);
  border-bottom:1px solid var(--gold-wash); padding-bottom:3px;
}

.art__body{ max-width:68ch; }
.asec{ margin-bottom:42px; }
.asec:last-child{ margin-bottom:0; }
.asec h2{
  font-size:clamp(1.4rem, 2.4vw, 1.85rem);
  margin-bottom:18px; scroll-margin-top:100px;
}
.asec p{ margin:0 0 18px; font-size:17.5px; line-height:1.7; }
.asec p:last-child{ margin-bottom:0; }
.asec strong{ font-weight:600; color:var(--ink-deep); }
.asec em{ font-style:italic; }

.bullets{ margin:0 0 20px; padding-left:22px; }
.bullets li{ margin-bottom:11px; font-size:17px; line-height:1.65; }

.callout{
  margin:0 0 22px; padding:18px 22px;
  background:var(--paper-tint);
  border-left:2px solid var(--gold);
  border-radius:0 3px 3px 0;
}
.callout p{ margin:0; font-size:16.5px; line-height:1.6; color:var(--ink-soft); }

.sheet--inline{ margin:0 0 24px; padding:20px 22px 14px; }
.sheet--inline .steps{ padding:16px 0 2px; }
.sheet--inline .step{ padding:10px 0 10px 24px; }
.sheet--inline .step__math{ font-size:clamp(17px, 1.9vw, 20px); }

.tablewrap{ overflow-x:auto; margin:0 0 24px; }
.tablewrap table{ width:100%; border-collapse:collapse; font-size:15.5px; }
.tablewrap th{
  text-align:left; padding:11px 14px 11px 0;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.12em;
  text-transform:uppercase; color:var(--gold); font-weight:500;
  border-bottom:1px solid var(--rule);
  white-space:nowrap;
}
.tablewrap td{
  padding:12px 14px 12px 0; vertical-align:top;
  border-bottom:1px solid var(--rule-soft); color:var(--ink-soft);
}
.tablewrap tr td:first-child{ color:var(--ink-deep); }

.graphblock{
  display:grid; grid-template-columns:1fr 1fr; gap:32px;
  margin:44px 0 0; padding:24px 26px;
  border:1px solid var(--rule); border-radius:var(--r);
}
.graphblock__label{
  font-family:var(--mono); font-size:10px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold); margin:0 0 12px;
}
.graphblock ul{ list-style:none; margin:0; padding:0; }
.graphblock li{ margin-bottom:8px; }
.graphblock a{
  font-family:var(--display); font-size:15px; text-decoration:none;
  border-bottom:1px solid transparent;
}
.graphblock a:hover{ color:var(--gold); border-bottom-color:var(--gold); }

.toolcta{
  margin-top:22px; padding:26px 28px;
  background:var(--panel); border-radius:var(--r);
}
.toolcta__label{
  font-family:var(--mono); font-size:10px; letter-spacing:.16em;
  text-transform:uppercase; color:var(--gold-bright); margin:0 0 10px;
}
.toolcta__text{
  margin:0 0 18px; font-size:16.5px; color:rgba(239,230,213,.8); max-width:44ch;
}
.toolcta .btn{ background:var(--gold); border-color:var(--gold); color:#0C1A31; }
.toolcta .btn:hover{ background:var(--gold-bright); border-color:var(--gold-bright); }

@media (max-width:1000px){
  .art__grid{ grid-template-columns:1fr; gap:34px; padding-top:34px; }
  .toc{
    position:static;
    padding:20px 22px; border:1px solid var(--rule); border-radius:var(--r);
  }
  .toc ol{ columns:2; column-gap:28px; }
}

@media (max-width:720px){
  .art__head{ padding:26px 0 26px; }
  .art__body{ max-width:none; }
  .asec p{ font-size:16.5px; }
  .toc ol{ columns:1; }
  .graphblock{ grid-template-columns:1fr; gap:22px; }
}

/* ============================================================
   THEME SWITCH — a pull-cord lamp
   Light theme = the light is on: the bulb glows and casts rays.
   Pull the cord (click, or Enter/Space) and it goes out.
   ============================================================ */

.lamp{
  position:relative;
  width:44px; height:44px; flex:none;
  padding:0; margin:0; border:0; background:none;
  cursor:pointer;
  -webkit-tap-highlight-color:transparent;
}
.lamp__flex{ display:block; }

.lamp__bulb{
  width:34px; height:46px;
  position:absolute; top:-13px; left:50%;
  transform:translateX(-50%);
  overflow:visible;
  stroke:var(--ink); stroke-width:1.6;
  transition:stroke .3s var(--ease);
}

/* the glass fills with warm light when the lamp is on */
.lamp__glass{
  fill:var(--gold-wash);
  transition:fill .35s var(--ease);
}
.lamp__filament{ stroke:var(--gold); transition:stroke .35s var(--ease); }
.lamp__cap{ stroke:var(--ink-soft); }

.lamp__rays{
  stroke:var(--gold);
  opacity:1;
  transform-origin:17px 16px;
  transition:opacity .3s var(--ease), transform .3s var(--ease);
}

/* the cord hangs from the cap and springs back after a pull */
.lamp__cord{
  position:absolute; left:50%; top:24px;
  width:1px; height:15px;
  background:var(--rule);
  transform-origin:top center;
  transition:transform .34s cubic-bezier(.2,1.5,.4,1);
}
.lamp__cord i{
  position:absolute; left:50%; bottom:-4px;
  width:5px; height:5px; margin-left:-2.5px;
  border-radius:50%;
  background:var(--gold);
}

/* pull */
.lamp:hover .lamp__cord,
.lamp:focus-visible .lamp__cord{ transform:scaleY(1.42); }
.lamp:active .lamp__cord{ transform:scaleY(1.85); transition-duration:.09s; }

.lamp:focus-visible{ outline:2px solid var(--gold); outline-offset:4px; border-radius:4px; }

/* ── light off: dark theme ───────────────────────────────── */

[data-theme="dark"] .lamp__bulb{ stroke:var(--ink-soft); }
[data-theme="dark"] .lamp__glass{ fill:transparent; }
[data-theme="dark"] .lamp__filament{ stroke:var(--ink-soft); opacity:.55; }
[data-theme="dark"] .lamp__cord i{ background:var(--ink-soft); }
[data-theme="dark"] .lamp__rays{ opacity:0; transform:scale(.55); }
[data-theme="dark"] .lamp:hover .lamp__bulb{ stroke:var(--gold); }

/* one warm flash across the page as the light comes on */
.flash{
  position:fixed; inset:0; z-index:200;
  pointer-events:none;
  background:radial-gradient(circle at 50% 0%,
             rgba(255,214,140,.5), rgba(255,214,140,0) 62%);
  opacity:0;
  animation:flash .5s var(--ease);
}
@keyframes flash{
  0%{ opacity:0; } 22%{ opacity:1; } 100%{ opacity:0; }
}

@media (prefers-reduced-motion:reduce){
  .lamp__cord{ transition:none; }
  .flash{ display:none; }
}

@media (max-width:720px){
  .lamp{ width:38px; height:38px; }
  .lamp__bulb{ width:29px; height:40px; top:-11px; }
  .lamp__cord{ top:20px; height:12px; }
}

/* A calculator that is planned but not built keeps its place in the list and
   its label, but its href is "#" — nothing on the site points at a URL that
   would 404. Clicking does nothing, so it must not look clickable. */
a.soon{ text-decoration:none; pointer-events:none; }

/* ── reviewer card ───────────────────────────────────────── */

.person{
  margin:0 0 40px; padding:28px 30px;
  border:1px solid var(--rule); border-radius:var(--r);
  background:var(--paper-raised);
  max-width:70ch;
}
.person__head{ display:flex; gap:18px; align-items:center; margin-bottom:22px; }
.person__mark{
  width:64px; height:64px; flex:none; border-radius:50%;
  background-image:url("/logonew.jpg");
  background-size:264%; background-position:50% 41%;
  background-color:#F9F1E4;
  border:1px solid var(--rule);
}
.person__name{
  font-family:var(--display); font-size:23px; font-weight:600;
  letter-spacing:-.02em; color:var(--ink-deep); margin:0;
}
.person__role{
  font-family:var(--mono); font-size:11px; letter-spacing:.1em;
  text-transform:uppercase; color:var(--gold); margin:7px 0 0;
}
.person__where{ margin:5px 0 0; font-size:15px; color:var(--ink-soft); }

.person__facts{
  display:grid; grid-template-columns:repeat(2, minmax(0,1fr));
  gap:14px 28px; margin:0 0 22px;
  padding:20px 0; border-top:1px solid var(--rule-soft);
  border-bottom:1px solid var(--rule-soft);
}
.person__facts dt{
  font-family:var(--mono); font-size:10px; letter-spacing:.14em;
  text-transform:uppercase; color:var(--ink-soft); margin-bottom:5px;
}
.person__facts dd{ margin:0; font-size:15.5px; line-height:1.45; color:var(--ink-deep); }

.person__links{ list-style:none; margin:0; padding:0; display:grid; gap:14px; }
.person__links li{ display:flex; flex-direction:column; gap:3px; }
.person__links a{
  font-family:var(--display); font-size:16px; color:var(--gold);
  text-decoration:none; border-bottom:1px solid var(--gold-wash);
  padding-bottom:2px; align-self:flex-start;
}
.person__links a:hover{ border-bottom-color:var(--gold); }
.person__links span{ font-size:14.5px; color:var(--ink-soft); }

@media (max-width:720px){
  .person{ padding:22px 20px; }
  .person__facts{ grid-template-columns:1fr; }
  .person__head{ gap:14px; }
  .person__mark{ width:52px; height:52px; }
}

/* ── learning stages ─────────────────────────────────────── */
/* A path reads left to right, so the stages sit side by side and each one is
   joined to the next by a rule. The numbering is not decoration: the order is
   the dependency order, which is the whole claim the section makes. */

.stages{
  list-style:none; margin:0; padding:0;
  display:grid; grid-template-columns:repeat(3, minmax(0,1fr));
  gap:28px;
}

.stage{
  position:relative;
  display:flex; flex-direction:column;
  padding:26px 26px 24px;
  border:1px solid var(--rule); border-radius:var(--r);
  background:var(--paper-raised);
}

/* the rule joining one stage to the next */
.stage:not(:last-child)::after{
  content:""; position:absolute; z-index:1;
  top:52px; right:-29px; width:28px; height:1px;
  background:var(--rule);
}
.stage:not(:last-child)::before{
  content:""; position:absolute; z-index:2;
  top:49px; right:-33px;
  width:6px; height:6px; border-radius:50%;
  background:var(--gold);
}

.stage__n{
  font-family:var(--mono); font-size:11px; letter-spacing:.16em;
  color:var(--gold);
}
.stage__head h3{
  font-size:22px; font-weight:500; margin:10px 0 10px;
}
.stage__head p{
  margin:0 0 20px; font-size:15.5px; line-height:1.55; color:var(--ink-soft);
}

.stage__list{
  list-style:none; margin:0 0 20px; padding:0;
  border-top:1px solid var(--rule-soft);
}
.stage__list li{ border-bottom:1px solid var(--rule-soft); }
.stage__list a{
  display:flex; align-items:baseline; justify-content:space-between; gap:14px;
  padding:11px 0;
  font-family:var(--display); font-size:15.5px;
  text-decoration:none; color:var(--ink-deep);
  transition:color .18s var(--ease);
}
.stage__list a:hover{ color:var(--gold); }
.stage__list em{
  flex:none;
  font-family:var(--mono); font-size:9.5px; font-style:normal;
  letter-spacing:.11em; text-transform:uppercase; color:var(--ink-soft);
}

.stage__tool{
  margin-top:auto; align-self:flex-start;
  font-family:var(--mono); font-size:10.5px; letter-spacing:.09em;
  text-transform:uppercase; text-decoration:none; color:var(--gold);
  border-bottom:1px solid var(--gold-wash); padding-bottom:3px;
  transition:border-color .18s var(--ease);
}
.stage__tool:hover{ border-bottom-color:var(--gold); }

.stages__hint{
  margin:26px 0 0; max-width:70ch;
  font-size:16px; color:var(--ink-soft);
}
.stages__hint a{ color:var(--gold); text-decoration:none;
                 border-bottom:1px solid var(--gold-wash); }
.stages__hint a:hover{ border-bottom-color:var(--gold); }

@media (max-width:980px){
  .stages{ grid-template-columns:1fr; gap:18px; }
  /* stacked, the joining rule runs downward instead */
  .stage:not(:last-child)::after{
    top:auto; bottom:-19px; right:auto; left:44px;
    width:1px; height:18px;
  }
  .stage:not(:last-child)::before{
    top:auto; bottom:-23px; right:auto; left:41px;
  }
}