@font-face{font-family:"Fraunces";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/fraunces-normal-latin.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Fraunces";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/fraunces-normal-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Fraunces";font-style:italic;font-weight:100 900;font-display:swap;src:url(fonts/fraunces-italic-latin.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Fraunces";font-style:italic;font-weight:100 900;font-display:swap;src:url(fonts/fraunces-italic-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Atkinson Hyperlegible Next";font-style:normal;font-weight:200 800;font-display:swap;src:url(fonts/AtkinsonHyperlegibleNext.woff2) format("woff2")}

:root{
  --bg:#f3ede2;--bg2:#e9e1d2;--surface:#fbf8f2;--ink:#1c1712;--muted:#4a4137;--line:#cdbfa8;--accent:#8c2a12;--focus:#1f4fd1;
  --chimp:#5e410f;--human:#1d4f63;--chimp-soft:#e4cf9f;--human-soft:#b9d5df;
  --rig-bone:#fcf8ef;--rig-bone-far:#e4dac6;--rig-ink:#3d3126;--rig-ink-far:#9a8a72;--rig-hole:#3d3126;--rig-accent:#c2401f;
  --rig-muscle:rgba(194,64,31,.22);--rig-cartilage:#cbbb9b;--rig-flesh:#caa27f;--rig-flesh-a:.34;--rig-ground:#8d7c63;--rig-label:#1c1712;--rig-label-muted:#4a4137;
  --serif:"Fraunces",Georgia,"Times New Roman",serif;--sans:"Atkinson Hyperlegible Next",system-ui,-apple-system,"Segoe UI",sans-serif;
  --bar:52px;color-scheme:light
}
:root[data-theme="dark"]{
  --bg:#110f0c;--bg2:#1a1612;--surface:#1d1915;--ink:#f1e9da;--muted:#cbbfa9;--line:#3a3229;--accent:#ff9774;--focus:#9cc2ff;
  --chimp:#f0c46a;--human:#8fd3ea;--chimp-soft:#4a3a1a;--human-soft:#173a47;
  --rig-bone:#eee3cc;--rig-bone-far:#7b7262;--rig-ink:#110f0c;--rig-ink-far:#110f0c;--rig-hole:#110f0c;--rig-accent:#ff7d57;
  --rig-muscle:rgba(255,125,87,.26);--rig-cartilage:#8f836d;--rig-flesh:#5f8196;--rig-flesh-a:.42;--rig-ground:#6f6452;--rig-label:#f1e9da;--rig-label-muted:#cbbfa9;
  color-scheme:dark
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
  --bg:#110f0c;--bg2:#1a1612;--surface:#1d1915;--ink:#f1e9da;--muted:#cbbfa9;--line:#3a3229;--accent:#ff9774;--focus:#9cc2ff;
  --chimp:#f0c46a;--human:#8fd3ea;--chimp-soft:#4a3a1a;--human-soft:#173a47;
  --rig-bone:#eee3cc;--rig-bone-far:#7b7262;--rig-ink:#110f0c;--rig-ink-far:#110f0c;--rig-hole:#110f0c;--rig-accent:#ff7d57;
  --rig-muscle:rgba(255,125,87,.26);--rig-cartilage:#8f836d;--rig-flesh:#5f8196;--rig-flesh-a:.42;--rig-ground:#6f6452;--rig-label:#f1e9da;--rig-label-muted:#cbbfa9;
  color-scheme:dark
}}

*{box-sizing:border-box}
html{scroll-padding-top:calc(var(--bar) + 12px);-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:400 1.0625rem/1.62 var(--sans)}
a{color:inherit;text-decoration-thickness:1px;text-underline-offset:.18em}
a:hover{text-decoration-thickness:2px}
:focus-visible{outline:3px solid var(--focus);outline-offset:3px;border-radius:4px}
.skip{position:absolute;left:-9999px;top:0;z-index:50;background:var(--surface);color:var(--ink);padding:.6rem 1rem}
.skip:focus{left:8px;top:8px}
sup{font-size:.62em;line-height:0}
html:not(.js) .needs-js{display:none!important}
.js .no-js-only{display:none!important}
.chimp{color:var(--chimp)}.human{color:var(--human)}
b.chimp,b.human,strong.chimp,strong.human{font-weight:700}

/* ---------- top bar ---------- */
.topbar{position:fixed;inset:0 0 auto 0;height:var(--bar);z-index:40;display:flex;align-items:center;gap:.9rem;padding:0 max(16px,3vw);
  background:color-mix(in srgb,var(--bg) 86%,transparent);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.topbar .home{font:600 .95rem/1 var(--serif);text-decoration:none;white-space:nowrap}
.topnav{display:flex;gap:1.1rem;overflow-x:auto;scrollbar-width:none;min-width:0;flex:0 1 auto}
.topnav::-webkit-scrollbar{display:none}
@media (max-width:560px){.topnav{-webkit-mask-image:linear-gradient(90deg,#000 75%,transparent);mask-image:linear-gradient(90deg,#000 75%,transparent);padding-right:1rem}}
.topnav a{font-size:.9rem;text-decoration:none;color:var(--muted);white-space:nowrap;padding:.4rem 0}
.topnav a:hover{color:var(--ink)}
.spacer{flex:1 1 0}
.chip{font-size:.85rem;text-decoration:none;border:1px solid var(--line);border-radius:999px;padding:.3rem .75rem;white-space:nowrap}
.icon-btn{width:36px;height:36px;border-radius:50%;border:1px solid var(--line);background:transparent;color:var(--ink);display:grid;place-items:center;cursor:pointer;flex:none}
.icon-btn svg{display:block}
.icon-btn svg[hidden]{display:none}

/* ---------- reading rail ---------- */
.rail{position:fixed;right:14px;top:50%;transform:translateY(-50%);z-index:30;display:flex;flex-direction:column;gap:12px}
.rail a{display:flex;align-items:center;justify-content:flex-end;gap:10px;text-decoration:none;color:var(--muted)}
.rail a span{font-size:.78rem;opacity:0;transform:translateX(6px);transition:opacity .2s,transform .2s;background:var(--surface);padding:.15rem .5rem;border-radius:6px;white-space:nowrap}
.rail a i{width:8px;height:8px;border-radius:50%;border:1.5px solid currentColor;display:block}
.rail a[aria-current] i{background:currentColor;transform:scale(1.25)}
.rail a:hover span,.rail a:focus-visible span{opacity:1;transform:none}
@media (max-width:1100px){.rail{display:none}}

/* ---------- hero ---------- */
.hero{position:relative;min-height:100svh;padding:calc(var(--bar) + 28px) max(16px,4vw) 28px;display:grid;
  grid-template-columns:minmax(0,34rem) minmax(0,1fr);grid-template-rows:auto 1fr auto;column-gap:2vw;
  background:radial-gradient(70% 60% at 68% 52%,var(--bg2),var(--bg) 72%)}
.hero-text{grid-column:1;grid-row:1 / span 2;align-self:center;position:relative;z-index:2}
.kicker{font-size:.85rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin:0 0 1rem}
h1{font:600 clamp(2.3rem,5.2vw,4.6rem)/1 var(--serif);letter-spacing:-.025em;margin:0;font-variation-settings:"opsz" 144;text-wrap:balance}
.deck{font-size:clamp(1.08rem,1.5vw,1.22rem);line-height:1.55;margin:1.2rem 0 0;text-wrap:pretty}
.byline{font-size:.85rem;color:var(--muted);margin:1rem 0 0}
.hero-fig{grid-column:2;grid-row:1 / span 2;position:relative;min-height:60svh;margin:0}
#hero-cv{position:absolute;inset:0;width:100%;height:100%;display:block}
.hero-fig .still{position:absolute;inset:0;display:flex;align-items:center;justify-content:center}
.js .hero-fig .still{display:none}
.hero-fig .still img{max-width:100%;max-height:100%;object-fit:contain}
.morph{grid-column:1 / -1;grid-row:3;position:relative;z-index:2;margin-top:.6rem}
.morph-row{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:0;position:relative}
.morph input[type=range]{position:absolute;left:10%;right:10%;width:80%;top:-6px;margin:0;height:28px;accent-color:var(--accent);background:transparent}
.stop{appearance:none;border:0;background:none;color:var(--muted);font:inherit;padding:30px 4px 6px;cursor:pointer;text-align:center;min-height:44px}
.stop b{display:block;font:600 1rem/1.15 var(--serif);color:var(--ink)}
.stop span{display:block;font-size:.8rem;line-height:1.3}
.stop[aria-pressed="true"] b{color:var(--accent)}
.morph-out{max-width:46rem;margin:.6rem auto 0;text-align:center;min-height:4.6em}
.morph-out .o-name{font:600 1.1rem/1.2 var(--serif)}
.morph-out .o-when{color:var(--muted);font-size:.9rem;margin-left:.4rem}
.morph-out .o-what{display:block;margin-top:.2rem}
.caveat{font-size:.9rem;color:var(--muted);max-width:46rem;margin:.5rem auto 0;text-align:center}
@media (max-width:820px){
  .hero{grid-template-columns:minmax(0,1fr);grid-template-rows:auto auto auto;padding-top:calc(var(--bar) + 18px)}
  .hero-text,.hero-fig,.morph{grid-column:1;grid-row:auto}
  .hero-fig{min-height:40svh;margin-top:0}
  .stop b{font-size:.88rem}.stop span{font-size:.72rem}
  .morph-out{text-align:left}.caveat{text-align:left}
}

/* ---------- prose sections ---------- */
.sec{padding:clamp(3rem,8vw,6rem) max(16px,4vw);max-width:72rem;margin:0 auto}
.sec>h2,.chapter h2{font:600 clamp(1.9rem,3.6vw,2.9rem)/1.05 var(--serif);letter-spacing:-.02em;margin:0 0 1rem;max-width:44rem;text-wrap:balance}
.sec>p,.prose p{max-width:40rem}
h2 a.anchor,h3 a.anchor{text-decoration:none}
h2 a.anchor:hover::after,h2 a.anchor:focus-visible::after{content:" #";color:var(--muted)}
.lede{font-size:1.2rem;line-height:1.55}
.chapter{padding:clamp(3rem,7vw,5rem) max(16px,4vw) 1rem;max-width:72rem;margin:0 auto}
.chapter .num{font:500 .85rem/1 var(--sans);letter-spacing:.14em;text-transform:uppercase;color:var(--accent);margin:0 0 .8rem}
.chapter p{max-width:40rem}

/* ---------- tour: sticky twin skeletons ---------- */
.tour{position:relative}
.tour .stage{position:sticky;top:var(--bar);height:calc(100svh - var(--bar));overflow:hidden}
.tour canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.tour .steps{position:relative;z-index:2;margin-top:calc(-100svh + var(--bar))}
.tour .step{min-height:92svh;display:flex;align-items:center;padding:2rem max(16px,4vw)}
.tour .step:last-child{min-height:100svh}
.card{max-width:24rem;background:color-mix(in srgb,var(--surface) 92%,transparent);border:1px solid var(--line);border-radius:14px;padding:1.2rem 1.3rem 1.3rem;
  box-shadow:0 18px 50px rgba(0,0,0,.12);backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px)}
.card h3{font:600 1.35rem/1.2 var(--serif);margin:.35rem 0 .2rem;letter-spacing:-.01em}
.card p{margin:.6rem 0 0}
.card .tag{font-size:.78rem;letter-spacing:.1em;text-transform:uppercase;color:var(--accent);margin:0}
.card .vs{display:grid;grid-template-columns:1fr 1fr;gap:.6rem;margin:.8rem 0 0}
.card .vs div{border-top:3px solid;padding-top:.35rem;font-size:.92rem;line-height:1.35}
.card .vs div:first-child{border-color:var(--chimp)}
.card .vs div:last-child{border-color:var(--human)}
.card .vs strong{display:block;font:600 1.5rem/1.1 var(--serif);font-variant-numeric:tabular-nums}
.card .fine{font-size:.88rem;color:var(--muted)}
.tour .still-tour{display:none}
html:not(.js) .tour .stage{display:none}
html:not(.js) .tour .steps{margin-top:0}
html:not(.js) .tour .step{min-height:0}
@media (min-width:821px){.tour .step{justify-content:flex-start}.tour .step.right{justify-content:flex-end}}
@media (max-width:820px){
  .tour .stage{height:48svh}
  .tour .steps{margin-top:-48svh}
  .tour .step{align-items:flex-start;min-height:115svh;padding-top:calc(48svh - var(--bar) + 10px)}
  .tour .step:last-child{min-height:120svh}
  .card{max-width:none;width:100%}
}

/* ---------- figures and widgets ---------- */
figure{margin:2rem 0}
figure.wide{max-width:64rem}
figure img{display:block;width:100%;height:auto;border-radius:6px}
figcaption{font-size:.9rem;color:var(--muted);margin-top:.6rem;max-width:44rem}
figcaption .credit{display:block;font-size:.8rem;margin-top:.25rem}
.widget{border:1px solid var(--line);border-radius:14px;background:var(--surface);padding:1.2rem;max-width:52rem;margin:2rem 0}
.widget h3{font:600 1.2rem/1.2 var(--serif);margin:0 0 .4rem}
.widget .note{font-size:.9rem;color:var(--muted);margin:.6rem 0 0}
.widget.failed .needs-js{display:none!important}
.btn{font:600 .95rem/1 var(--sans);color:var(--ink);background:transparent;border:1px solid var(--line);border-radius:999px;padding:.7rem 1.1rem;min-height:44px;cursor:pointer}
.btn[aria-pressed="true"],.btn.primary{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.row{display:flex;gap:.6rem;flex-wrap:wrap;align-items:center}
.bars{display:grid;gap:.7rem;margin-top:.8rem}
.bar{display:grid;grid-template-columns:minmax(8rem,13rem) 1fr minmax(4.5rem,auto);gap:.7rem;align-items:center}
.bar .track{height:28px;width:100%;display:block;background:var(--bg2);border-radius:4px}
.bar .fill.c{fill:var(--chimp)}.bar .fill.h{fill:var(--human)}
.bar .v{font-variant-numeric:tabular-nums;font-weight:700}
svg text{font-family:var(--sans)}
.chart{width:100%;height:auto;display:block}
.chart .axis{stroke:var(--line)}
.chart .lab{fill:var(--muted);font-size:12px}
.chart .c{fill:var(--chimp)}.chart .h{fill:var(--human)}

/* ---------- after ---------- */
.after{border-top:1px solid var(--line)}
.srcs{padding-left:1.1rem;font-size:.92rem;max-width:52rem}
.srcs li{margin:.35rem 0}
.method{max-width:44rem;color:var(--muted)}
.foot{padding:2rem max(16px,4vw) 3rem;border-top:1px solid var(--line);font-size:.9rem;color:var(--muted)}
.nf main{padding:20vh 16px;text-align:center}

/* ---------- components ---------- */
.visually-hidden{position:absolute!important;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.share{display:flex;flex-wrap:wrap;gap:.4rem;align-items:center;margin-top:1rem;font-size:.9rem}
.share a,.share button{display:inline-flex;align-items:center;min-height:44px;padding:0 .9rem;border:1px solid var(--line);border-radius:999px;text-decoration:none;color:var(--ink);background:transparent;font:inherit;cursor:pointer}
.share-note{color:var(--muted);font-size:.85rem}
.split{display:grid;grid-template-columns:minmax(0,40rem) minmax(0,1fr);gap:3rem;align-items:start}
@media (max-width:900px){.split{grid-template-columns:1fr;gap:1rem}}
.pair{display:grid;grid-template-columns:1fr 1fr;gap:1rem;align-items:start;max-width:64rem}
.pair figure{margin:0}
@media (max-width:560px){.pair{grid-template-columns:1fr}}
.prose h3{font:600 1.3rem/1.2 var(--serif);margin:2rem 0 .4rem}
.after-tour{padding-top:1rem}
.squares{display:grid;grid-template-columns:1fr 1fr;gap:1rem;max-width:30rem;margin-top:.8rem}
.squares figure{margin:0}
.skin{width:100%;height:auto;display:block}
.skin rect{fill:var(--bg2);stroke:var(--line)}
.skin.c circle{fill:var(--chimp)}.skin.h circle{fill:var(--human)}
.lanes{display:grid;gap:.9rem;margin-top:.8rem}
.lane{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:.2rem .8rem;align-items:center}
.lane .who{font-size:.92rem;grid-column:1 / -1}
.lane .track{position:relative;height:18px;border-bottom:1px dashed var(--line)}
.lane .ball{position:absolute;top:2px;left:0;width:14px;height:14px;border-radius:50%}
.lane .ball.c{background:var(--chimp)}.lane .ball.h{background:var(--human)}
.lane .spd{font-size:.85rem;font-variant-numeric:tabular-nums;white-space:nowrap}
.lane .t{grid-column:1 / -1;font-size:.8rem;color:var(--muted);min-height:1em}
html:not(.js) .lane .ball,.race:not(.ready) .ball{left:calc(100% - 14px)!important}
.bar>span:first-child{font-size:.9rem;line-height:1.25}
@media (max-width:560px){.bar{grid-template-columns:1fr auto;}.bar .track{grid-column:1 / -1;grid-row:2}.bar .v{grid-row:1;grid-column:2}}
.widget label{display:inline-flex;align-items:center;gap:.4rem;font-size:.95rem}
.widget input,.widget select{font:inherit;color:var(--ink);background:var(--bg);border:1px solid var(--line);border-radius:8px;padding:.45rem .6rem;min-height:44px}
.widget input{width:5.5rem}
.widget input[aria-invalid=true]{border-color:var(--accent)}
.chart-fig{max-width:60rem}
.chart .band.c{fill:var(--chimp-soft)}.chart .band.h{fill:var(--human-soft)}
.chart .bandlab{fill:var(--ink);font-weight:600}
.chart .pt{fill:var(--accent);fill-opacity:.85;stroke:var(--bg);stroke-width:1}
.chart .mark{stroke:var(--ink);stroke-dasharray:3 4;stroke-width:1}
.chart .mk{fill:var(--ink);font-size:12px}
.chart .lifebar.c{fill:var(--chimp)}.chart .lifebar.h{fill:var(--human)}
.chart .tick{stroke:var(--ink);stroke-width:1.5}
.chart .who{fill:var(--ink);font-size:13px;font-weight:600}
.stops-text{max-width:46rem;margin:.6rem auto 0;padding-left:1.2rem}
.stops-text li{margin:.4rem 0}
.js .hero-fig.no-canvas .still{display:flex}
.tour.no-canvas .stage{display:none}
.tour.no-canvas .steps{margin-top:0}
.tour.no-canvas .step{min-height:0}
@media (max-width:360px){.topbar{gap:.5rem;padding:0 10px}.topbar .home{font-size:.85rem}.chip{padding:.3rem .55rem}}
@media (max-width:380px){.stop{padding-left:1px;padding-right:1px}.stop b{font-size:.74rem;overflow-wrap:anywhere}.stop span{font-size:.66rem}}
.srcs a{overflow-wrap:anywhere}
@media (min-width:1101px){.morph{margin-right:32px}}