/* ============================================================
   Dynamic Navigator — HERS
   Single committed dark instrument-panel palette.
   Every colour is painted explicitly; no theme inheritance.
   ============================================================ */
:root{
  color-scheme: dark;

  /* neutrals, biased slightly cool-teal toward the accent */
  --ground:#0A0F11;
  --surface:#10171A;
  --surface-2:#151F23;
  --line:#1E2B30;
  --line-soft:#182328;

  /* ink */
  --ink:#E6EDF0;
  --ink-2:#B6C4CA;
  --ink-muted:#87979E;
  --ink-faint:#5E6F76;

  /* accent + validated categorical series (dark mode, OKLCH band 0.48–0.67) */
  --accent:#34D3AF;
  --accent-deep:#12A88C;
  --s-hydraulic:#12A88C;
  --s-kinetic:#4A93E8;
  --s-thermal:#C2801F;
  --neutral-series:#7C8B93;

  --maxw:1120px;
  --prose:66ch;

  --step--1:0.8125rem;
  --step-0:1.0625rem;
  --step-1:1.25rem;
  --step-2:1.55rem;
  --step-3:2.05rem;
  --step-4:2.9rem;
  --step-5:clamp(2.25rem,4.4vw,3.35rem);
}

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

body{
  margin:0;
  background:var(--ground);
  color:var(--ink);
  font-family:"Source Serif 4",Georgia,"Times New Roman",serif;
  font-size:var(--step-0);
  line-height:1.72;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3,h4{
  font-family:Archivo,"Helvetica Neue",Arial,sans-serif;
  font-weight:600;
  letter-spacing:-0.02em;
  line-height:1.12;
  text-wrap:balance;
  margin:0;
  color:var(--ink);
}
p{margin:0;}
a{color:var(--accent);text-decoration:none;}
a:hover{text-decoration:underline;}
a:focus-visible,button:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:2px;}

.mono{font-family:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,monospace;}

/* ---------- layout primitives ---------- */
.wrap{max-width:var(--maxw);margin-inline:auto;padding-inline:20px;}
.stack{display:flex;flex-direction:column;}
.prose{max-width:var(--prose);}
.prose p + p{margin-top:0.9em;}

.eyebrow{
  font-family:"IBM Plex Mono",ui-monospace,monospace;
  font-size:0.71rem;
  letter-spacing:0.16em;
  text-transform:uppercase;
  color:var(--accent);
  margin:0;
}
.eyebrow--muted{color:var(--ink-faint);}

section.band{padding-block:clamp(56px,7vw,104px);border-top:1px solid var(--line-soft);}
section.band:first-of-type{border-top:0;}
.band__head{display:flex;flex-direction:column;gap:14px;margin-bottom:38px;}
.band__head h2{font-size:var(--step-3);}
.band__head .lede{color:var(--ink-2);max-width:62ch;}

/* ---------- header ---------- */
header.site{
  position:sticky;top:0;z-index:40;
  background:rgba(10,15,17,0.88);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line-soft);
}
.site__inner{
  max-width:var(--maxw);margin-inline:auto;padding:12px 20px;
  display:flex;align-items:center;gap:26px;flex-wrap:wrap;
}
.brand{display:flex;align-items:center;gap:11px;text-decoration:none;color:var(--ink);}
.brand:hover{text-decoration:none;}
.brand__name{font-family:Archivo,sans-serif;font-weight:700;font-size:0.95rem;letter-spacing:-0.01em;line-height:1.1;}
.brand__sub{font-family:"IBM Plex Mono",monospace;font-size:0.62rem;letter-spacing:0.15em;text-transform:uppercase;color:var(--ink-faint);}
nav.site__nav{display:flex;gap:20px;flex-wrap:wrap;margin-left:auto;}
nav.site__nav a{
  font-family:"IBM Plex Mono",monospace;font-size:0.73rem;letter-spacing:0.06em;
  color:var(--ink-2);text-transform:uppercase;
}
nav.site__nav a:hover{color:var(--accent);text-decoration:none;}
.btn{
  display:inline-block;font-family:Archivo,sans-serif;font-weight:600;font-size:0.84rem;
  letter-spacing:-0.005em;padding:9px 16px;border-radius:3px;
  background:var(--accent);color:#04211B;border:1px solid var(--accent);
}
.btn:hover{background:#4FE0BF;text-decoration:none;}
.btn--ghost{background:transparent;color:var(--ink);border-color:var(--line);}
.btn--ghost:hover{background:var(--surface-2);border-color:var(--accent);color:var(--accent);}

/* ---------- hero ---------- */
.hero{padding-block:clamp(48px,6.5vw,86px) clamp(40px,5vw,64px);}
.hero__grid{display:grid;grid-template-columns:minmax(0,1fr);gap:44px;}
@media(min-width:1000px){.hero__grid{grid-template-columns:minmax(0,0.86fr) minmax(0,1.14fr);gap:52px;align-items:center;}}
.split{display:grid;gap:34px;grid-template-columns:minmax(0,1fr);}
@media(min-width:1000px){.split{grid-template-columns:minmax(0,1.18fr) minmax(0,0.82fr);gap:44px;align-items:start;}}
.stackfigs{display:grid;gap:26px;grid-template-columns:minmax(0,1fr);}
.hero h1{font-size:var(--step-5);font-weight:700;letter-spacing:-0.033em;margin-top:18px;}
.hero h1 em{font-style:normal;color:var(--accent);}
.hero__lede{margin-top:20px;color:var(--ink-2);font-size:1.1rem;max-width:52ch;}
.hero__cta{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px;}

.chips{display:grid;grid-template-columns:repeat(auto-fit,minmax(142px,1fr));margin-top:34px;border-top:1px solid var(--line);}
.chip{padding:16px 18px 14px 0;border-right:1px solid var(--line-soft);}
.chip + .chip{padding-left:18px;}
.chip:last-child{border-right:0;}
.chip__v{font-family:Archivo,sans-serif;font-weight:700;font-size:1.5rem;letter-spacing:-0.025em;color:var(--ink);font-variant-numeric:tabular-nums;}
.chip__v span{font-size:0.82rem;font-weight:500;color:var(--ink-muted);margin-left:3px;}
.chip__k{font-family:"IBM Plex Mono",monospace;font-size:0.66rem;letter-spacing:0.11em;text-transform:uppercase;color:var(--ink-faint);margin-top:4px;}

/* ---------- figures ---------- */
figure{margin:0;}
.fig{
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:4px;
  padding:22px 22px 16px;
  overflow-x:auto;
}
.fig svg{display:block;width:100%;max-width:100%;height:auto;min-width:460px;}
.fig figcaption{
  margin-top:14px;padding-top:12px;border-top:1px solid var(--line-soft);
  font-size:0.85rem;color:var(--ink-muted);line-height:1.6;min-width:0;
}
.fig figcaption b{color:var(--ink-2);font-weight:600;}

/* diagram type inside svg */
.d-label{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:11.5px;fill:var(--ink-2);}
.d-label--sm{font-size:10px;fill:var(--ink-faint);letter-spacing:0.04em;}
.d-title{font-family:Archivo,sans-serif;font-size:13px;font-weight:600;fill:var(--ink);}
.d-box{fill:var(--surface-2);stroke:var(--line);stroke-width:1;}
.d-stroke{stroke:var(--ink-faint);stroke-width:1.4;fill:none;}
.d-num{font-family:"IBM Plex Mono",monospace;font-size:11px;fill:var(--accent);}

/* ---------- pathway sections ---------- */
.pathway{border-top:1px solid var(--line-soft);padding-top:38px;margin-top:44px;}
.pathway:first-of-type{border-top:0;padding-top:0;margin-top:0;}
.pathway__head{display:flex;align-items:baseline;gap:14px;flex-wrap:wrap;margin-bottom:8px;}
.pathway__tag{
  font-family:"IBM Plex Mono",monospace;font-size:0.68rem;letter-spacing:0.12em;text-transform:uppercase;
  padding:3px 9px;border-radius:2px;border:1px solid currentColor;
}
.t-kinetic{color:var(--s-kinetic);}
.t-hydraulic{color:var(--s-hydraulic);}
.t-thermal{color:var(--s-thermal);}
.pathway h3{font-size:var(--step-2);}
.pathway__body{display:grid;gap:28px;margin-top:20px;}
@media(min-width:900px){
  .pathway__body{grid-template-columns:minmax(0,1.25fr) minmax(0,0.75fr);align-items:start;gap:40px;}
  .pathway__body > figure{grid-column:1 / -1;}
}
.pathway__side .spec{margin-top:0;}

.spec{border-top:1px solid var(--line);margin-top:22px;}
.spec dl{display:grid;grid-template-columns:auto 1fr;gap:0;margin:0;}
.spec dt,.spec dd{
  padding:9px 0;border-bottom:1px solid var(--line-soft);margin:0;
  font-family:"IBM Plex Mono",monospace;font-size:0.78rem;line-height:1.5;
}
.spec dt{color:var(--ink-faint);padding-right:22px;letter-spacing:0.04em;}
.spec dd{color:var(--ink);text-align:right;font-variant-numeric:tabular-nums;}

.eq{
  font-family:"IBM Plex Mono",monospace;font-size:0.84rem;color:var(--ink-2);
  background:var(--surface);border-left:2px solid var(--accent-deep);
  padding:12px 16px;margin-top:18px;border-radius:0 3px 3px 0;line-height:1.8;
  overflow-x:auto;
}
.eq b{color:var(--accent);font-weight:400;}

/* ---------- driver cards ---------- */
.drivers{display:grid;gap:1px;background:var(--line-soft);border:1px solid var(--line-soft);border-radius:4px;overflow:hidden;}
@media(min-width:720px){.drivers{grid-template-columns:repeat(2,minmax(0,1fr));}}
@media(min-width:1040px){.drivers{grid-template-columns:repeat(4,minmax(0,1fr));}}
.driver{background:var(--surface);padding:24px 22px 26px;display:flex;flex-direction:column;gap:9px;}
.driver__k{font-family:"IBM Plex Mono",monospace;font-size:0.65rem;letter-spacing:0.13em;text-transform:uppercase;color:var(--accent);}
.driver h3{font-size:1.02rem;letter-spacing:-0.012em;}
.driver p{font-size:0.9rem;color:var(--ink-2);line-height:1.62;}
.driver .when{
  margin-top:auto;padding-top:12px;font-family:"IBM Plex Mono",monospace;font-size:0.7rem;
  color:var(--ink-faint);border-top:1px solid var(--line-soft);
}

/* ---------- tables ---------- */
.tablewrap{overflow-x:auto;border:1px solid var(--line);border-radius:4px;background:var(--surface);}
table{border-collapse:collapse;width:100%;min-width:560px;font-size:0.88rem;}
caption{text-align:left;padding:16px 18px 0;font-family:"IBM Plex Mono",monospace;font-size:0.68rem;letter-spacing:0.13em;text-transform:uppercase;color:var(--ink-faint);}
th,td{padding:11px 18px;text-align:left;border-bottom:1px solid var(--line-soft);vertical-align:top;}
thead th{
  font-family:"IBM Plex Mono",monospace;font-size:0.68rem;letter-spacing:0.09em;text-transform:uppercase;
  color:var(--ink-faint);font-weight:400;border-bottom:1px solid var(--line);
}
td.num,th.num{text-align:right;font-family:"IBM Plex Mono",monospace;font-variant-numeric:tabular-nums;white-space:nowrap;}
tbody tr:last-child td{border-bottom:0;}
tr.total td{border-top:1px solid var(--line);background:var(--surface-2);font-weight:600;color:var(--ink);}
.swatch{display:inline-block;width:9px;height:9px;border-radius:2px;margin-right:9px;vertical-align:baseline;}

/* ---------- esg matrix ---------- */
.esg{display:grid;gap:18px;}
@media(min-width:880px){.esg{grid-template-columns:repeat(3,minmax(0,1fr));}}
.esg__col{background:var(--surface);border:1px solid var(--line);border-radius:4px;padding:24px 22px;display:flex;flex-direction:column;gap:14px;}
.esg__letter{
  font-family:Archivo,sans-serif;font-weight:700;font-size:2.2rem;line-height:1;
  color:var(--accent-deep);letter-spacing:-0.04em;
}
.esg__col h3{font-size:1.02rem;}
.esg__col ul{margin:0;padding-left:0;list-style:none;display:flex;flex-direction:column;gap:11px;}
.esg__col li{font-size:0.88rem;color:var(--ink-2);line-height:1.6;padding-left:16px;position:relative;}
.esg__col li::before{content:"";position:absolute;left:0;top:0.62em;width:6px;height:1px;background:var(--accent-deep);}
.esg__col li b{color:var(--ink);font-weight:600;}
.frameworks{margin-top:auto;padding-top:14px;border-top:1px solid var(--line-soft);display:flex;flex-wrap:wrap;gap:6px;}
.fw{
  font-family:"IBM Plex Mono",monospace;font-size:0.66rem;letter-spacing:0.05em;
  color:var(--ink-muted);border:1px solid var(--line);border-radius:2px;padding:2px 7px;
}

/* ---------- stages ---------- */
.stages{display:grid;gap:1px;background:var(--line-soft);border:1px solid var(--line-soft);border-radius:4px;overflow:hidden;}
@media(min-width:860px){.stages{grid-template-columns:repeat(4,minmax(0,1fr));}}
.stage{background:var(--surface);padding:24px 22px;display:flex;flex-direction:column;gap:10px;}
.stage__n{font-family:"IBM Plex Mono",monospace;font-size:0.72rem;color:var(--accent);letter-spacing:0.1em;}
.stage h3{font-size:0.98rem;}
.stage p{font-size:0.87rem;color:var(--ink-2);line-height:1.6;}
.stage .dur{margin-top:auto;padding-top:12px;border-top:1px solid var(--line-soft);font-family:"IBM Plex Mono",monospace;font-size:0.7rem;color:var(--ink-faint);}

/* ---------- notes / assumptions ---------- */
.note{
  background:var(--surface);border:1px solid var(--line);border-left:2px solid var(--s-thermal);
  border-radius:0 4px 4px 0;padding:20px 22px;
}
.note h4{font-size:0.9rem;margin-bottom:8px;}
.note p,.note li{font-size:0.85rem;color:var(--ink-muted);line-height:1.65;}
.note ul{margin:8px 0 0;padding-left:18px;display:flex;flex-direction:column;gap:5px;}

/* ---------- contact ---------- */
.contact{display:grid;gap:30px;}
@media(min-width:880px){.contact{grid-template-columns:minmax(0,1.1fr) minmax(0,0.9fr);gap:48px;}}
.contact__card{background:var(--surface);border:1px solid var(--line);border-radius:4px;padding:26px 24px;}
.contact__row{display:flex;gap:16px;padding:12px 0;border-bottom:1px solid var(--line-soft);align-items:baseline;}
.contact__row:last-child{border-bottom:0;}
.contact__k{font-family:"IBM Plex Mono",monospace;font-size:0.67rem;letter-spacing:0.12em;text-transform:uppercase;color:var(--ink-faint);min-width:84px;}
.contact__v{font-size:0.92rem;color:var(--ink);}

/* ---------- footer ---------- */
footer.site{border-top:1px solid var(--line-soft);padding-block:40px 56px;background:var(--surface);}
footer.site .cols{display:grid;gap:26px;}
@media(min-width:800px){footer.site .cols{grid-template-columns:minmax(0,1.2fr) minmax(0,2fr);gap:48px;}}
footer.site p,footer.site li{font-size:0.8rem;color:var(--ink-faint);line-height:1.65;}
footer.site h4{font-family:"IBM Plex Mono",monospace;font-size:0.66rem;letter-spacing:0.13em;text-transform:uppercase;color:var(--ink-muted);font-weight:400;margin-bottom:10px;}
footer.site ol{margin:0;padding-left:18px;display:flex;flex-direction:column;gap:6px;}
footer.site a{color:var(--ink-muted);}

/* ---------- chart tooltip ---------- */
.charthost{position:relative;}
#tip{
  position:fixed;z-index:80;pointer-events:none;opacity:0;transition:opacity .09s;
  background:#0A1214;border:1px solid var(--line);border-radius:3px;padding:7px 10px;
  font-family:"IBM Plex Mono",monospace;font-size:0.72rem;color:var(--ink);
  box-shadow:0 6px 20px rgba(0,0,0,0.5);white-space:nowrap;line-height:1.5;
}
#tip.on{opacity:1;}
#tip .t-k{color:var(--ink-faint);}

@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;}}


/* ============================================================
   Multi-page navigation
   ============================================================ */
nav.site__nav a.is-active{color:var(--accent);}
nav.site__nav a.is-active::after{content:"";display:block;height:1px;background:var(--accent);margin-top:4px;}

.pagehead{padding-block:clamp(38px,5vw,66px) 0;}
.pagehead .eyebrow{margin-bottom:14px;}
.pagehead h1{font-size:var(--step-4);letter-spacing:-0.03em;}
.pagehead h1 em{font-style:normal;color:var(--accent);}
.pagehead .lede{color:var(--ink-2);max-width:62ch;margin-top:16px;font-size:1.06rem;}
.pagehead + section.band{border-top:0;padding-top:clamp(30px,3.6vw,46px);}

.pagenav{max-width:var(--maxw);margin-inline:auto;display:grid;gap:1px;background:var(--line-soft);
  border-top:1px solid var(--line-soft);border-bottom:1px solid var(--line-soft);}
@media(min-width:720px){.pagenav{grid-template-columns:repeat(2,minmax(0,1fr));}}
.pagenav__item{display:flex;flex-direction:column;gap:6px;background:var(--ground);padding:26px 20px;text-decoration:none;}
.pagenav__item:hover{background:var(--surface);text-decoration:none;}
.pagenav__item--next{align-items:flex-end;text-align:right;}
.pagenav__k{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:0.66rem;letter-spacing:0.13em;
  text-transform:uppercase;color:var(--ink-faint);}
.pagenav__t{font-family:Archivo,sans-serif;font-weight:600;font-size:1.02rem;color:var(--ink);letter-spacing:-0.015em;}
.pagenav__item:hover .pagenav__t{color:var(--accent);}

.pagecards{display:grid;gap:1px;background:var(--line-soft);border:1px solid var(--line-soft);border-radius:4px;overflow:hidden;}
@media(min-width:720px){.pagecards{grid-template-columns:repeat(2,minmax(0,1fr));}}
@media(min-width:1040px){.pagecards{grid-template-columns:repeat(3,minmax(0,1fr));}}
.pagecard{background:var(--surface);padding:26px 22px;display:flex;flex-direction:column;gap:10px;text-decoration:none;}
.pagecard:hover{background:var(--surface-2);text-decoration:none;}
.pagecard__k{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:0.65rem;letter-spacing:0.13em;
  text-transform:uppercase;color:var(--accent);}
.pagecard h3{font-size:1.05rem;color:var(--ink);}
.pagecard p{font-size:0.88rem;color:var(--ink-2);line-height:1.6;}
.pagecard__go{margin-top:auto;padding-top:12px;border-top:1px solid var(--line-soft);
  font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:0.7rem;color:var(--ink-faint);}
.pagecard:hover .pagecard__go{color:var(--accent);}

.defs-hidden{position:absolute;width:0;height:0;overflow:hidden;}
.skip{position:absolute;left:-9999px;}
.skip:focus{left:12px;top:12px;z-index:90;background:var(--accent);color:#04211B;padding:8px 14px;border-radius:3px;}