/* =========================================================================
   EXPLAINER PAGE LAYER (candidate for platform/shared/neuropsych-explainer.css)
   The devices that make /engine/ read as crafted, lifted verbatim where
   possible so the engine page can adopt this file with one markup change
   (data-explainer on <body>). Tokens only. Scoped to [data-explainer] so
   nothing leaks into other pages.
   ========================================================================= */
[data-explainer]{font-family:var(--font-body);background:var(--bg);color:var(--ink);line-height:1.6;font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
[data-explainer] *{box-sizing:border-box}
:where([data-explainer]) a{color:var(--teal);text-decoration:none}
:where([data-explainer]) a:hover{text-decoration:underline;text-underline-offset:3px}
[data-explainer] b,[data-explainer] strong{font-weight:600}
[data-explainer] .wrap{max-width:1100px;margin:0 auto;padding-left:clamp(24px,6vw,80px);padding-right:clamp(24px,6vw,80px)}

/* text link with a sliding arrow */
[data-explainer] .text-link{display:inline-flex;align-items:center;gap:6px;font-weight:600;color:var(--teal);font-size:14.5px;min-height:44px}
[data-explainer] .text-link .ico{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;transition:transform .3s var(--ease)}
[data-explainer] .text-link:hover .ico{transform:translateX(3px)}

/* ===== HERO ===== */
[data-explainer] .hero{position:relative;padding:120px 0 64px;background:linear-gradient(180deg,rgba(14,116,144,.075) 0%,rgba(14,116,144,.03) 42%,#ffffff 78%);overflow:hidden}
[data-explainer] .hero .wrap{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.92fr);gap:clamp(32px,6vw,72px);align-items:center}
[data-explainer] .overline{display:flex;align-items:center;flex-wrap:wrap;gap:6px 10px;margin-bottom:18px}
[data-explainer] .overline .ov-k{display:inline-flex;align-items:center;gap:8px;font-size:11px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--teal)}
[data-explainer] .overline .ov-k::before{content:'';width:20px;height:2px;background:var(--teal)}
[data-explainer] .overline i{width:3px;height:3px;border-radius:50%;background:var(--text3)}
[data-explainer] .overline em{font-style:normal;font-size:13.5px;font-weight:500;color:var(--text2);letter-spacing:0}
[data-explainer] .hero h1{font-family:var(--font-display);font-size:clamp(36px,5.2vw,58px);font-weight:800;letter-spacing:-.04em;line-height:1.05;margin:0 0 20px;color:var(--ink);text-wrap:balance}
[data-explainer] .hero h1 em{font-style:normal;color:var(--teal)}
[data-explainer] .hero-body{font-size:17px;color:var(--text2);max-width:540px;line-height:1.7;margin:0 0 28px}
[data-explainer] .hero-actions{display:flex;align-items:center;gap:12px 20px;flex-wrap:wrap}
@keyframes heIn{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
.js [data-explainer] .he{animation:heIn .8s var(--ease) both;animation-delay:calc(var(--i,0)*80ms + 60ms)}

/* worked object: the one elevated surface on the page */
[data-explainer] .ex{background:#fff;border:1px solid var(--line);border-radius:var(--r-card);box-shadow:0 1px 2px rgba(0,0,0,.04),0 12px 32px -12px rgba(15,76,92,.18);padding:22px 22px 18px;position:relative}
[data-explainer] .ex-h{display:flex;justify-content:space-between;align-items:baseline;gap:12px;margin-bottom:4px}
[data-explainer] .ex-h b{font-family:var(--font-display);font-size:14.5px;font-weight:700;letter-spacing:-.01em}
[data-explainer] .ex-h span{font-family:var(--font-data);font-size:11px;color:var(--text3);letter-spacing:.04em;white-space:nowrap}
[data-explainer] .ex-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
[data-explainer] .ex-grid.three{grid-template-columns:repeat(3,1fr)}
[data-explainer] .ex-k{display:block;font-size:10.5px;text-transform:uppercase;letter-spacing:.08em;color:var(--text3);font-weight:600;margin-bottom:2px}
[data-explainer] .ex-v{display:block;font-family:var(--font-data);font-size:19px;font-weight:500;color:var(--ink);line-height:1.2;font-variant-numeric:tabular-nums}
[data-explainer] .ex-v small{font-family:var(--font-body);font-size:11.5px;font-weight:500;color:var(--text3);margin-left:2px}
[data-explainer] .ex-v.q{color:var(--teal-deep)}
[data-explainer] .ex-eq{margin-top:14px;padding-top:12px;border-top:1px dashed var(--line-strong);font-family:var(--font-data);font-size:12px;line-height:1.85;color:var(--text2);overflow-x:auto}
[data-explainer] .ex-eq div{white-space:nowrap}
[data-explainer] .ex-eq b{font-weight:500;color:var(--ink)}
[data-explainer] .ex-src{margin:10px 0 0;font-size:11.5px;color:var(--text3);line-height:1.5}
[data-explainer] .ex-src a{color:var(--text2)}

/* ===== NUMBERS STRIP ===== */
[data-explainer] .nums{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:#fff}
[data-explainer] .nums .wrap{display:grid;grid-template-columns:repeat(var(--n,5),1fr);padding-left:clamp(12px,4vw,80px);padding-right:clamp(12px,4vw,80px)}
[data-explainer] .num{padding:26px 18px 24px;border-left:1px solid var(--line)}
[data-explainer] .num:first-child{border-left:0}
[data-explainer] .num b{display:block;font-family:var(--font-data);font-size:30px;font-weight:500;letter-spacing:-.02em;color:var(--ink);line-height:1.1;font-variant-numeric:tabular-nums}
[data-explainer] .num span{display:block;font-size:12.5px;color:var(--text2);margin-top:7px;line-height:1.45}

/* ===== SECTIONS ===== */
[data-explainer] .sec{padding:84px 0}
[data-explainer] .sec-white{background:#fff}
[data-explainer] .sec-tint{background:var(--teal-tint)}
[data-explainer] .section-label{display:flex;align-items:center;gap:8px;font-size:11px;font-weight:600;letter-spacing:.12em;text-transform:uppercase;color:var(--teal);margin:0 0 14px}
[data-explainer] .section-label::before{content:'';width:20px;height:2px;background:var(--teal)}
[data-explainer] .section-title{font-family:var(--font-display);font-size:clamp(28px,4vw,38px);font-weight:800;letter-spacing:-.035em;line-height:1.1;margin:0 0 12px;color:var(--ink);text-wrap:balance}
[data-explainer] .section-title em{font-style:normal;color:var(--teal)}
[data-explainer] .section-desc{font-size:16px;color:var(--text2);max-width:560px;line-height:1.7;margin:0 0 40px}
[data-explainer] .section-desc a{font-weight:500}

/* ===== PIPELINE (vertical ring numerals with a drawing spine) ===== */
[data-explainer] .legend{display:flex;flex-wrap:wrap;gap:8px 22px;font-family:var(--font-data);font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);margin:-16px 0 36px}
[data-explainer] .legend i,[data-explainer] .step-who i{display:inline-block;width:9px;height:9px;border-radius:50%;background:var(--teal);margin-right:7px;vertical-align:0}
[data-explainer] .legend .m i,[data-explainer] .step.model .step-who i{background:none;border:1.5px dashed var(--teal-deep)}
[data-explainer] .pipe{position:relative;max-width:840px}
[data-explainer] .pipe.wide{max-width:none}
[data-explainer] .pipe::before{content:'';position:absolute;left:19px;top:20px;bottom:36px;width:2px;background:rgba(14,116,144,.28);transform-origin:top}
.js [data-explainer] .pipe::before{transform:scaleY(0);transition:transform 1.6s var(--ease) .2s}
.js [data-explainer] [data-rv].in .pipe::before{transform:scaleY(1)}
[data-explainer] .step{position:relative;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:0 22px;padding-bottom:44px}
[data-explainer] .step:last-child{padding-bottom:0}
[data-explainer] .step-n{width:40px;height:40px;border-radius:50%;background:#fff;border:2px solid var(--teal);display:flex;align-items:center;justify-content:center;font-family:var(--font-data);font-size:12px;font-weight:600;color:var(--teal);position:relative;z-index:1}
[data-explainer] .step.model .step-n,[data-explainer] .step.open .step-n{border-style:dashed;color:var(--teal-deep);border-color:var(--teal-deep);background:#fff}
[data-explainer] .step h3{font-family:var(--font-display);font-size:19px;font-weight:700;letter-spacing:-.02em;margin:8px 0 8px;color:var(--ink)}
[data-explainer] .step p{font-size:15px;color:var(--text2);line-height:1.7;max-width:62ch;margin:0}
[data-explainer] .step p+p{margin-top:10px}
[data-explainer] .step p.q{color:var(--ink);font-size:15.5px}
[data-explainer] .step-who{font-family:var(--font-data);font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);padding-top:13px;white-space:nowrap}
[data-explainer] .step.model .step-who{color:var(--teal-deep)}
[data-explainer] .step dl{display:grid;grid-template-columns:auto minmax(0,1fr);gap:6px 16px;margin:12px 0 0;font-size:14.5px;line-height:1.65}
[data-explainer] .step dt{font-weight:600;color:var(--ink);white-space:nowrap}
[data-explainer] .step dd{margin:0;color:var(--text2);max-width:60ch}

/* ===== PIPELINE, HORIZONTAL (four stops on a drawing line) ===== */
[data-explainer] .pipe-h{position:relative;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0 28px}
[data-explainer] .pipe-h::before{content:'';position:absolute;left:20px;right:20px;top:19px;height:2px;background:rgba(14,116,144,.28);transform-origin:left}
.js [data-explainer] .pipe-h::before{transform:scaleX(0);transition:transform 1.6s var(--ease) .2s}
.js [data-explainer] [data-rv].in .pipe-h::before{transform:scaleX(1)}
[data-explainer] .pipe-h .stop{position:relative}
[data-explainer] .pipe-h .step-n{margin-bottom:14px}
[data-explainer] .pipe-h .stop h3{font-family:var(--font-display);font-size:17.5px;font-weight:700;letter-spacing:-.02em;margin:0 0 8px;color:var(--ink)}
[data-explainer] .pipe-h .stop p{font-size:14.5px;color:var(--text2);line-height:1.65;margin:0}
[data-explainer] .pipe-h .stop-who{display:block;font-family:var(--font-data);font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);margin-bottom:6px}

/* ===== HAIRLINE TABLE ===== */
[data-explainer] .srcs{width:100%;border-collapse:collapse;font-size:14px}
[data-explainer] .srcs th{text-align:left;font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--text3);font-weight:600;padding:0 16px 10px 0;border-bottom:1px solid var(--line-strong)}
[data-explainer] .srcs td{padding:13px 16px 13px 0;border-bottom:1px solid var(--line);vertical-align:top;line-height:1.55}
[data-explainer] .srcs td:first-child{font-weight:600;color:var(--ink);white-space:nowrap;width:1%}
[data-explainer] .srcs td:nth-child(2){color:var(--text2)}
[data-explainer] .srcs td:last-child{color:var(--text3);font-size:13px;padding-right:0;font-variant-numeric:tabular-nums}
[data-explainer] .srcs tr:last-child td{border-bottom:0}
[data-explainer] .panel{margin-top:36px;padding:22px 24px;background:var(--surface-2);border-radius:var(--r)}
[data-explainer] .panel h4{font-family:var(--font-display);font-size:15.5px;font-weight:700;letter-spacing:-.015em;margin:0 0 6px}
[data-explainer] .panel p{font-size:14.5px;color:var(--text2);line-height:1.65;margin:0}
[data-explainer] .panel p+p{margin-top:8px}
[data-explainer] .srcs-note{margin:22px 0 0;font-size:13.5px;color:var(--text3);line-height:1.6;max-width:70ch}

/* ===== TWO-COLUMN INTRO ===== */
[data-explainer] .two{display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);gap:24px clamp(32px,6vw,80px);align-items:start}
[data-explainer] .two .section-desc{margin-bottom:0}
[data-explainer] .two .body p{font-size:15.5px;color:var(--text2);line-height:1.75;margin:0}
[data-explainer] .two .body p+p{margin-top:14px}

/* ===== RULES (two-column hairline list) ===== */
[data-explainer] .rules{display:grid;grid-template-columns:1fr 1fr;gap:0 clamp(28px,5vw,64px);border-top:1px solid var(--line-strong)}
[data-explainer] .rules.one{grid-template-columns:1fr}
[data-explainer] .rule{padding:24px 0;border-bottom:1px solid var(--line)}
[data-explainer] .rule h4{font-family:var(--font-display);font-size:16.5px;font-weight:700;letter-spacing:-.015em;margin:0 0 6px;color:var(--ink)}
[data-explainer] .rule p{font-size:14.5px;color:var(--text2);line-height:1.65;margin:0}
[data-explainer] .rule .text-link{min-height:0;margin-top:8px;font-size:14px}

/* ===== LEDGER (filled dot = in place, hollow dot = not yet) ===== */
[data-explainer] .ledger{display:grid;grid-template-columns:1fr 1fr;gap:0 clamp(28px,5vw,64px)}
[data-explainer] .ledger h3{display:flex;align-items:center;gap:10px;font-family:var(--font-display);font-size:16px;font-weight:700;letter-spacing:-.015em;margin:0;padding:0 0 12px;border-bottom:1px solid var(--line-strong);color:var(--ink)}
[data-explainer] .ledger h3::before{content:'';width:11px;height:11px;border-radius:50%;background:var(--teal);flex:none}
[data-explainer] .ledger .open h3::before{background:#fff;box-shadow:inset 0 0 0 2px var(--teal-deep)}
[data-explainer] .ledger ul{list-style:none;margin:0;padding:0}
[data-explainer] .ledger li{position:relative;padding:16px 0 16px 24px;border-bottom:1px solid var(--line);font-size:14.5px;line-height:1.6;color:var(--text2)}
[data-explainer] .ledger li::before{content:'';position:absolute;left:2px;top:1.35em;width:8px;height:8px;border-radius:50%;background:var(--teal)}
[data-explainer] .ledger .open li::before{background:#fff;box-shadow:inset 0 0 0 1.5px var(--teal-deep)}
[data-explainer] .ledger li b{color:var(--ink)}

/* ===== DEFINITION LIST (term left, text right) ===== */
[data-explainer] .tech{display:grid;grid-template-columns:220px minmax(0,1fr);gap:0 40px;border-top:1px solid var(--line-strong);margin:0}
[data-explainer] .tech.wide{grid-template-columns:280px minmax(0,1fr)}
[data-explainer] .tech dt{font-family:var(--font-display);font-size:15px;font-weight:700;letter-spacing:-.01em;padding:22px 0;border-bottom:1px solid var(--line);color:var(--ink)}
[data-explainer] .tech dt small{display:block;font-family:var(--font-data);font-size:11px;font-weight:500;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);margin-top:4px}
[data-explainer] .tech dd{font-size:14.5px;color:var(--text2);line-height:1.7;padding:22px 0;border-bottom:1px solid var(--line);margin:0}
[data-explainer] .tech dd code{font-family:var(--font-data);font-size:12.5px;background:var(--surface-2);padding:2px 6px;border-radius:8px;color:var(--ink)}
[data-explainer] .tech dd p{margin:0}
[data-explainer] .tech dd p+p{margin-top:8px}
[data-explainer] .tech dd .text-link{min-height:0;margin-top:8px;font-size:14px}
[data-explainer] .note{margin-top:40px;background:var(--surface-2);border-radius:var(--r);padding:20px 24px;font-size:14px;color:var(--text2);line-height:1.65;max-width:78ch}
[data-explainer] .note strong{color:var(--ink)}
[data-explainer] .cta{margin-top:44px;display:flex;gap:12px 20px;flex-wrap:wrap;align-items:center}

/* ===== THE ASK (one question and one secondary button closing a section) ===== */
[data-explainer] .ask{display:flex;justify-content:space-between;align-items:center;gap:16px 32px;flex-wrap:wrap;border-top:1px solid var(--line-strong);padding-top:24px;margin-top:44px}
[data-explainer] .ask p{font-family:var(--font-display);font-size:18px;font-weight:700;letter-spacing:-.02em;margin:0;color:var(--ink)}
[data-explainer] .ask p small{display:block;font-family:var(--font-body);font-size:14px;font-weight:400;color:var(--text2);margin-top:4px;letter-spacing:0}

/* ===== REVEAL ===== */
.js [data-explainer] [data-rv] .rv{opacity:0;transform:translateY(18px);transition:opacity .7s var(--ease),transform .7s var(--ease);transition-delay:calc(var(--i,0)*80ms)}
.js [data-explainer] [data-rv].in .rv{opacity:1;transform:none}
.js [data-explainer] [data-rv] .rv-row{opacity:0;transition:opacity .6s var(--ease);transition-delay:calc(var(--i,0)*45ms + .2s)}
.js [data-explainer] [data-rv].in .rv-row{opacity:1}
/* bars that grow on reveal: set --w inline */
.js [data-explainer] [data-rv] .grow{transform:scaleX(0);transform-origin:left;transition:transform 1s var(--ease);transition-delay:calc(var(--i,0)*60ms + .3s)}
.js [data-explainer] [data-rv].in .grow{transform:scaleX(1)}

/* ===== RESPONSIVE ===== */
@media(max-width:1000px){
  [data-explainer] .two{grid-template-columns:1fr}
  [data-explainer] .tech,[data-explainer] .tech.wide{grid-template-columns:180px 1fr}
}
@media(max-width:900px){
  [data-explainer] .hero .wrap{grid-template-columns:1fr;gap:36px}
  [data-explainer] .hero{padding-top:104px}
  [data-explainer] .nums .wrap{grid-template-columns:repeat(3,1fr)}
  [data-explainer] .num:nth-child(4){border-left:0}
  [data-explainer] .num{border-top:1px solid var(--line)}
  [data-explainer] .num:nth-child(-n+3){border-top:0}
  [data-explainer] .rules{grid-template-columns:1fr}
  [data-explainer] .ledger{grid-template-columns:1fr;gap:32px 0}
  [data-explainer] .pipe-h{grid-template-columns:1fr;gap:28px 0;padding-left:0}
  [data-explainer] .pipe-h::before{left:19px;right:auto;top:20px;bottom:40px;width:2px;height:auto;transform-origin:top}
  .js [data-explainer] .pipe-h::before{transform:scaleY(0)}
  .js [data-explainer] [data-rv].in .pipe-h::before{transform:scaleY(1)}
  [data-explainer] .pipe-h .stop{display:grid;grid-template-columns:40px minmax(0,1fr);gap:0 22px}
  [data-explainer] .pipe-h .step-n{margin:0}
  [data-explainer] .pipe-h .stop h3{margin-top:8px}
}
@media(max-width:700px){
  [data-explainer] .sec{padding:64px 0}
  [data-explainer] .step{grid-template-columns:40px minmax(0,1fr)}
  [data-explainer] .step-who{grid-column:2;padding-top:0;margin-top:-4px;margin-bottom:10px;order:-1}
  [data-explainer] .step h3{margin-top:0}
  [data-explainer] .step-n{grid-row:1/span 3}
  [data-explainer] .step dl{grid-template-columns:1fr;gap:2px 0}
  [data-explainer] .step dd{margin-bottom:8px}
  [data-explainer] .srcs thead{display:none}
  [data-explainer] .srcs tr{display:block;padding:14px 0;border-bottom:1px solid var(--line)}
  [data-explainer] .srcs td{display:block;border:0;padding:2px 0}
  [data-explainer] .srcs td:first-child{white-space:normal;width:auto}
  [data-explainer] .tech,[data-explainer] .tech.wide{grid-template-columns:1fr}
  [data-explainer] .tech dt{padding:20px 0 4px;border-bottom:0}
  [data-explainer] .tech dd{padding:0 0 20px}
}
@media(max-width:600px){
  [data-explainer] .nums .wrap{grid-template-columns:1fr 1fr}
  [data-explainer] .num{border-top:1px solid var(--line);padding:20px 14px 18px}
  [data-explainer] .num:nth-child(-n+3){border-top:1px solid var(--line)}
  [data-explainer] .num:nth-child(-n+2){border-top:0}
  [data-explainer] .num:nth-child(odd){border-left:0}
  [data-explainer] .num:nth-child(even){border-left:1px solid var(--line)}
  [data-explainer] .num b{font-size:26px}
  [data-explainer] .ex{padding:18px 16px 14px}
  [data-explainer] .ex-grid,[data-explainer] .ex-grid.three{grid-template-columns:1fr 1fr;gap:12px 8px}
}
@media(max-width:480px){
  [data-explainer] .hero-actions>a{width:100%}
  [data-explainer] .ask>a{width:100%}
}
@media(prefers-reduced-motion:reduce){
  .js [data-explainer] .he{animation:none}
  .js [data-explainer] [data-rv] .rv,.js [data-explainer] [data-rv] .rv-row{opacity:1;transform:none;transition:none}
  .js [data-explainer] .pipe::before,.js [data-explainer] .pipe-h::before{transform:none;transition:none}
  .js [data-explainer] [data-rv] .grow{transform:none;transition:none}
}