:root{
  --bg:#F6F3EC; --surface:#FFFDF8; --ink:#1C2126; --muted:#56646A; --rule:#D9D3C7;
  --teal:#003E52; --teal2:#4F7A86; --ochre:#C9962B; --ochre-ink:#8A6414; --fade:rgba(28,33,38,.10);
  --g0:#003E52; --g1:#3E7C8A; --g2:#93BCC0; --g3:#7B6A55; --g4:#BFB39C;
  --serif:"Newsreader", "Iowan Old Style", Georgia, serif;
  --sans:"Public Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono:"IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    color-scheme:dark;
    --bg:#0F171B; --surface:#152127; --ink:#E8E4DA; --muted:#9AA7A9; --rule:#2A383E;
    --teal:#6FB3C4; --teal2:#5E98A5; --ochre:#E0B04F; --ochre-ink:#E0B04F; --fade:rgba(232,228,218,.10);
    --g0:#6FB3C4; --g1:#3A8494; --g2:#C8DEDD; --g3:#A8937A; --g4:#6E6554;
  }
}
:root[data-theme="dark"]{
  color-scheme:dark;
  --bg:#0F171B; --surface:#152127; --ink:#E8E4DA; --muted:#9AA7A9; --rule:#2A383E;
  --teal:#6FB3C4; --teal2:#5E98A5; --ochre:#E0B04F; --ochre-ink:#E0B04F; --fade:rgba(232,228,218,.10);
  --g0:#6FB3C4; --g1:#3A8494; --g2:#C8DEDD; --g3:#A8937A; --g4:#6E6554;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion: reduce){html{scroll-behavior:auto}}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:17px;line-height:1.6;padding-inline:clamp(16px,4vw,48px);-webkit-font-smoothing:antialiased}
a{color:var(--teal);text-underline-offset:3px}
a:focus-visible,button:focus-visible,input:focus-visible+label{outline:2px solid var(--ochre);outline-offset:3px;border-radius:3px}
h1,h2,h3{font-family:var(--serif);font-weight:500;text-wrap:balance;margin:0;letter-spacing:-.01em}
p{margin:0}
.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--teal2)}
.wrap{max-width:1180px;margin-inline:auto}

/* header */
.top{display:flex;align-items:center;justify-content:space-between;gap:1rem;flex-wrap:wrap;padding-block:20px;max-width:1180px;margin-inline:auto;border-bottom:1px solid var(--rule)}
.brand{font-family:var(--serif);font-size:20px;font-weight:500;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:10px}
.brand i{display:inline-block;width:10px;height:10px;border-radius:50%;background:var(--ochre)}
.top nav{display:flex;gap:1.25rem;flex-wrap:wrap;font-size:14px}
.top nav a{color:var(--muted);text-decoration:none}
.top nav a:hover{color:var(--ink)}

/* story */
.story{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:clamp(24px,4vw,64px);max-width:1180px;margin-inline:auto}
.steps{grid-column:1;grid-row:1}
.stage{grid-column:2;grid-row:1;position:sticky;top:env(safe-area-inset-top,0px);height:100vh;height:100svh;display:flex;flex-direction:column;justify-content:center;gap:12px;padding-block:24px}
.step{min-height:88vh;display:flex;flex-direction:column;justify-content:center;gap:14px;padding-block:40px;transition:opacity .4s}
.step:not(.on){opacity:.55}
.step.hero{min-height:92vh}
.step h2{font-size:clamp(26px,3vw,34px);line-height:1.15}
.step p{max-width:34em;color:var(--ink)}
.step .note{font-size:14px;color:var(--muted)}
.hero h1{font-size:clamp(36px,5vw,60px);line-height:1.04;font-weight:400}
.hero h1 em{font-style:italic;color:var(--teal)}
.hero .lede{font-size:19px;color:var(--muted);max-width:30em}
.ctas{display:flex;gap:12px;flex-wrap:wrap;margin-top:8px}
.btn{font:500 15px/1 var(--sans);padding:13px 18px;border-radius:999px;border:1px solid var(--rule);background:var(--surface);color:var(--ink);text-decoration:none;cursor:pointer;display:inline-flex;align-items:center;gap:8px}
.btn.primary{background:var(--ochre);border-color:var(--ochre);color:#1C2126}
.btn.primary:hover{filter:brightness(1.06)}
.btn .tag{font-family:var(--mono);font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.rewards{font-family:var(--mono);font-size:13px;color:var(--muted);display:flex;flex-wrap:wrap;gap:6px}
.rewards span{border:1px solid var(--rule);border-radius:4px;padding:2px 8px;background:var(--surface)}
.key{font-family:var(--serif);font-style:italic;font-size:clamp(21px,2.2vw,26px);line-height:1.3;color:var(--teal);border-left:3px solid var(--ochre);padding-left:16px;max-width:30em}

.counter{display:flex;justify-content:space-between;align-items:baseline;gap:12px;font-family:var(--mono);font-size:13px;color:var(--muted)}
.counter b{font-weight:500;color:var(--ink);font-size:15px}
.canvas-box{position:relative;flex:1;min-height:0}
canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.bars{display:grid;gap:7px;font-family:var(--mono);font-size:12px;color:var(--muted)}
.bar{display:grid;grid-template-columns:11.5em 1fr;gap:10px;align-items:center}
.bar .track{display:flex;height:9px;border-radius:2px;overflow:hidden;background:var(--fade)}
.bar .track i{display:block;height:100%;transition:width .5s}
.bar.empty .track{opacity:.4}
.legend{font-size:12px;color:var(--muted);display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.legend .sw{display:inline-flex;gap:3px}
.legend .sw i{width:9px;height:9px;border-radius:50%;display:inline-block}

.draw-ui{display:flex;flex-direction:column;gap:14px;padding:18px;border:1px solid var(--rule);border-radius:10px;background:var(--surface);max-width:34em}
.seg{display:inline-flex;border:1px solid var(--rule);border-radius:999px;padding:3px;gap:2px;flex-wrap:wrap}
.seg input{position:absolute;opacity:0;pointer-events:none}
.seg label{font-size:14px;padding:7px 14px;border-radius:999px;cursor:pointer;color:var(--muted)}
.seg input:checked+label{background:var(--teal);color:var(--bg)}
.draw-row{display:flex;gap:14px;align-items:center;flex-wrap:wrap}
.drawn-count{font-family:var(--mono);font-size:13px;color:var(--muted)}

/* sections */
section.block{max-width:1180px;margin-inline:auto;padding-block:clamp(64px,9vw,112px);border-top:1px solid var(--rule);display:grid;gap:36px}
.block-head{display:grid;gap:14px;max-width:44em}
.block-head h2{font-size:clamp(30px,3.6vw,44px);line-height:1.1}
.block-head p{color:var(--muted);font-size:18px}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,300px),1fr));gap:1px;background:var(--rule);border:1px solid var(--rule);border-radius:10px;overflow:hidden}
.card{background:var(--surface);padding:22px;display:grid;gap:10px;align-content:start}
.card h3{font-size:22px}
.card .q{font-size:15px}
.card .not{font-size:14px;color:var(--muted);border-top:1px dashed var(--rule);padding-top:10px}
.card .not b{font-family:var(--mono);font-weight:500;font-size:11px;letter-spacing:.08em;text-transform:uppercase;display:block;margin-bottom:2px;color:var(--teal2)}

.axis{display:grid;gap:22px}
.oneaxis{display:flex;align-items:center;gap:14px;font-family:var(--serif);font-size:22px;color:var(--muted)}
.oneaxis .line{flex:1;height:2px;background:var(--rule);position:relative}
.oneaxis .line::before,.oneaxis .line::after{content:"";position:absolute;top:-5px;width:0;height:0;border:6px solid transparent}
.oneaxis .line::before{left:-6px;border-right-color:var(--rule);border-left:0}
.oneaxis .line::after{right:-6px;border-left-color:var(--rule);border-right:0}
.oneaxis s{text-decoration-thickness:1.5px}
.questions{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,260px),1fr));gap:10px}
.questions li{padding:14px 16px;border:1px solid var(--rule);border-radius:8px;background:var(--surface);font-size:15px;display:grid;gap:6px}
.questions li.hit{border-color:var(--ochre);box-shadow:inset 0 0 0 1px var(--ochre)}
.questions li.hit small{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--ochre-ink)}

.comp{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,200px),1fr));gap:24px}
.comp div{display:grid;gap:8px;align-content:start;border-top:2px solid var(--teal);padding-top:14px}
.comp h3{font-size:20px}
.comp p{font-size:15px;color:var(--muted)}
.expert{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:clamp(20px,4vw,56px);align-items:start;background:var(--surface);border:1px solid var(--rule);border-radius:10px;padding:clamp(20px,3vw,36px)}
.expert p{font-size:16px}
.expert .stack{display:grid;gap:14px}

.split{display:grid;grid-template-columns:1fr 1fr;gap:clamp(20px,4vw,56px)}
.split h3{font-size:24px;margin-bottom:12px}
.split ul{margin:0;padding:0;list-style:none;display:grid;gap:10px}
.split li{padding-left:22px;position:relative;font-size:16px}
.split .gone li::before{content:"";position:absolute;left:2px;top:.72em;width:12px;height:1.5px;background:var(--teal)}
.split .stays li::before{content:"";position:absolute;left:3px;top:.45em;width:8px;height:8px;border-radius:50%;border:1.5px solid var(--ochre)}

.badge{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;border:1px solid var(--ochre);color:var(--ochre-ink);padding:3px 8px;border-radius:4px;justify-self:start}
.pipe{list-style:none;margin:0;padding:0;display:grid;counter-reset:p}
.pipe li{display:grid;grid-template-columns:44px minmax(0,1.1fr) minmax(0,1fr) minmax(0,1fr);gap:16px;padding-block:18px;border-top:1px solid var(--rule);counter-increment:p;align-items:start}
.pipe li:last-child{border-bottom:1px solid var(--rule)}
.pipe li::before{content:counter(p,decimal-leading-zero);font-family:var(--mono);font-size:13px;color:var(--teal2);padding-top:4px}
.pipe h3{font-size:20px}
.pipe .body{font-size:14px;color:var(--muted);margin-top:2px}
.mech{display:inline-block;margin-top:8px;font-family:var(--mono);font-size:12px;padding:2px 8px;border-radius:4px;border:1px solid var(--rule)}
.mech.lot{border-color:var(--ochre);color:var(--ochre-ink)}
.pipe .col{font-size:14px}
.pipe .col b{display:block;font-family:var(--mono);font-weight:500;font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin-bottom:3px}
.pipe-head{display:grid;grid-template-columns:44px minmax(0,1.1fr) minmax(0,1fr) minmax(0,1fr);gap:16px;font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);padding-bottom:8px}

.pilots{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:0}
.pilots li{display:grid;grid-template-columns:120px 1fr;gap:16px;padding-block:14px;border-top:1px solid var(--rule);font-size:16px}
.pilots li span{font-family:var(--mono);font-size:12px;color:var(--teal2);padding-top:3px}

.timeline{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,210px),1fr));gap:22px}
.timeline li{display:grid;gap:6px;align-content:start;position:relative;padding-top:22px}
.timeline li::before{content:"";position:absolute;top:0;left:0;right:-22px;height:1px;background:var(--rule)}
.timeline li::after{content:"";position:absolute;top:-4px;left:0;width:9px;height:9px;border-radius:50%;background:var(--teal)}
.timeline li.now::after{background:var(--ochre)}
.timeline .when{font-family:var(--mono);font-size:13px;color:var(--teal2)}
.timeline h3{font-size:19px}
.timeline p{font-size:14px;color:var(--muted)}

.paper{display:grid;grid-template-columns:minmax(0,7fr) minmax(0,4fr);gap:clamp(24px,4vw,56px);align-items:start}
.paper .abs{font-size:16px;display:grid;gap:14px}
.paper h3{font-size:clamp(24px,2.6vw,32px);line-height:1.15}
.meta{display:grid;gap:14px;background:var(--surface);border:1px solid var(--rule);border-radius:10px;padding:22px;font-size:14px}
.meta dt{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.meta dd{margin:2px 0 0}
.closing{font-family:var(--serif);font-size:clamp(24px,3vw,36px);line-height:1.25;max-width:26em;font-weight:400}
footer{max-width:1180px;margin-inline:auto;border-top:1px solid var(--rule);padding-block:28px 40px;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;font-size:13px;color:var(--muted)}

@media (max-width:860px){
  body{font-size:16px}
  .story{grid-template-columns:minmax(0,1fr);gap:0}
  .stage{grid-column:1;grid-row:1;height:52vh;height:52svh;z-index:2;background:var(--bg);padding-block:10px;border-bottom:1px solid var(--rule)}
  .steps{grid-column:1;grid-row:2;position:relative;z-index:1}
  .step{min-height:70vh;min-height:70svh;justify-content:flex-start;padding-block:28px 40px}
  .step.hero{min-height:auto;padding-top:24px}
  .step:not(.on){opacity:.75}
  .bar{grid-template-columns:9.5em 1fr}
  .legend{display:none}
  .expert,.split,.paper{grid-template-columns:minmax(0,1fr)}
  .pipe li,.pipe-head{grid-template-columns:32px minmax(0,1fr)}
  .pipe-head{display:none}
  .pipe .col{grid-column:2}
  .pilots li{grid-template-columns:minmax(0,1fr);gap:4px}
}
@media (prefers-reduced-motion: reduce){.step,.bar .track i{transition:none}}

/* shared: nav state, subpage hero, copy */
.top nav a[aria-current="page"]{color:var(--ink);text-decoration:underline;text-decoration-color:var(--ochre);text-decoration-thickness:2px;text-underline-offset:6px}
.page-hero{max-width:1180px;margin-inline:auto;padding-block:clamp(48px,7vw,88px) clamp(32px,4vw,48px);display:grid;gap:16px}
.page-hero h1{font-size:clamp(36px,5vw,58px);line-height:1.05;font-weight:400;max-width:18em}
.page-hero p{font-size:19px;color:var(--muted);max-width:40em}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{font:500 13px/1 var(--sans);padding:8px 12px;border-radius:999px;border:1px solid var(--rule);background:var(--surface);color:var(--muted);cursor:pointer}
.chip[aria-pressed="true"]{background:var(--teal);border-color:var(--teal);color:var(--bg)}
.tag{font-family:var(--mono);font-size:11px;letter-spacing:.06em;text-transform:uppercase;padding:3px 8px;border-radius:4px;border:1px solid var(--rule);color:var(--muted);white-space:nowrap}
.tag.ok{border-color:var(--teal2);color:var(--teal)}
.tag.design{border-color:var(--ochre);color:var(--ochre-ink)}
.tag.open{border-style:dashed;border-color:var(--muted);color:var(--muted)}
.tag.critic{border-color:var(--ochre);color:var(--ochre-ink)}
@media (max-width:520px){.top nav{gap:.9rem}.top nav a[href='index.html#paper']{display:none}}