@font-face{font-family:"Newsreader";font-style:normal;font-weight:200 800;font-display:swap;src:url(fonts/newsreader-latin.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Newsreader";font-style:normal;font-weight:200 800;font-display:swap;src:url(fonts/newsreader-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,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:"Newsreader";font-style:italic;font-weight:400;font-display:swap;src:url(fonts/newsreader-italic-400-latin.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Newsreader";font-style:italic;font-weight:400;font-display:swap;src:url(fonts/newsreader-italic-400-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,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:"Plex Mono";font-style:normal;font-weight:400;font-display:swap;src:url(fonts/IBMPlexMono-Regular.woff2) format("woff2")}

/* Sandstone and ink by day; the city at dusk by night. */
:root{
  --bg:#f3eee4;--bg-2:#e9e1d1;--card:#fbf8f2;--ink:#1c1a16;--ink-2:#3d3931;--rule:#d3c8b3;--rule-2:#8a8070;
  --accent:#8f2f16;--link:#1f3f86;--green:#2c5a2e;
  --map-bg:#ece5d7;--map-ghost:rgba(60,50,35,.10);
  --g-stone:#d8cfbe;--g-roof:#ece6da;--g-cut:#b8452b;--g-low:#e3a21f;--g-sel:#2f6fb3;--g-garden:#2f8a3e;--g-fog:#f3eee4;
  --y0:#4d1636;--y1:#8f2a2e;--y2:#c75a28;--y3:#e3a13a;--y4:#a8b957;--y5:#4f9f8f;--y6:#2f6aa6;
  --bar-bg:rgba(243,238,228,.93);
  color-scheme:light;
}
:root[data-theme="dark"]{
  --bg:#111316;--bg-2:#181b20;--card:#1b1f25;--ink:#efebe3;--ink-2:#cdc6b9;--rule:#2d323a;--rule-2:#69717d;
  --accent:#f2a27e;--link:#9fc0ff;--green:#9fd49a;
  --map-bg:#15181c;--map-ghost:rgba(230,220,200,.07);
  --g-stone:#6f6a62;--g-roof:#8a847a;--g-cut:#e0674a;--g-low:#f0b43a;--g-sel:#6aa9f0;--g-garden:#6cc26f;--g-fog:#111316;
  --y0:#8e3b6b;--y1:#c24a4a;--y2:#e0763a;--y3:#f0b545;--y4:#bfd46a;--y5:#6cc3b0;--y6:#6ea6e6;
  --bar-bg:rgba(17,19,22,.9);
  color-scheme:dark;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --bg:#111316;--bg-2:#181b20;--card:#1b1f25;--ink:#efebe3;--ink-2:#cdc6b9;--rule:#2d323a;--rule-2:#69717d;
    --accent:#f2a27e;--link:#9fc0ff;--green:#9fd49a;
    --map-bg:#15181c;--map-ghost:rgba(230,220,200,.07);
    --g-stone:#6f6a62;--g-roof:#8a847a;--g-cut:#e0674a;--g-low:#f0b43a;--g-sel:#6aa9f0;--g-garden:#6cc26f;--g-fog:#111316;
    --y0:#8e3b6b;--y1:#c24a4a;--y2:#e0763a;--y3:#f0b545;--y4:#bfd46a;--y5:#6cc3b0;--y6:#6ea6e6;
    --bar-bg:rgba(17,19,22,.9);
    color-scheme:dark;
  }
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;overflow-x:clip}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{margin:0;background:var(--bg);color:var(--ink);font:400 1.1875rem/1.62 "Newsreader",Georgia,serif;font-optical-sizing:auto;overflow-x:clip}
a{color:var(--link);text-underline-offset:.18em;text-decoration-thickness:1px}
a:hover{text-decoration-thickness:2px}
:focus-visible{outline:3px solid var(--accent);outline-offset:3px;border-radius:3px}
img{max-width:100%;height:auto;display:block}
b,strong{font-weight:640}
.num{font-family:"Plex Mono",ui-monospace,monospace;font-size:.86em;letter-spacing:-.01em}
.skip{position:absolute;left:-999px;top:0;background:var(--card);color:var(--ink);padding:.5rem .8rem;z-index:99}
.skip:focus{left:.5rem;top:.5rem}
[hidden]{display:none!important}

/* ---- top bar ---- */
.topbar{position:sticky;top:0;z-index:40;display:flex;align-items:center;gap:.9rem;height:2.75rem;padding:0 1rem;background:var(--bar-bg);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-bottom:1px solid var(--rule);font-size:.9rem}
.topbar a{color:var(--ink);text-decoration:none}
.topbar .home{font-weight:600;white-space:nowrap}
.topnav{display:flex;gap:1rem;overflow-x:auto;scrollbar-width:none;min-width:0;flex:0 1 auto}
.topnav::-webkit-scrollbar{display:none}
.topnav a{white-space:nowrap;color:var(--ink-2)}
.topnav a:hover,.topnav a[aria-current="true"]{color:var(--ink);text-decoration:underline}
.spacer{flex:1 1 0}
.langs{position:relative;flex:none}
.langs summary{list-style:none;display:block;cursor:pointer;border:1px solid var(--rule-2);border-radius:99px;padding:.1rem .65rem;font-size:.82rem;white-space:nowrap;line-height:1.6;-webkit-user-select:none;user-select:none}
.langs summary span{display:inline-flex;align-items:center;gap:.35rem;pointer-events:none}
.langs summary::-webkit-details-marker{display:none}
.langs summary span::after{content:"";width:.4em;height:.4em;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg) translateY(-2px)}
.langs ul{position:absolute;right:0;top:calc(100% + .4rem);margin:0;padding:.3rem;list-style:none;background:var(--card);border:1px solid var(--rule);border-radius:8px;box-shadow:0 8px 24px rgba(0,0,0,.15);min-width:9.5rem}
.langs li a{display:block;padding:.45rem .7rem;border-radius:5px;color:var(--ink)}
.langs li a:hover,.langs li a:focus-visible{background:var(--bg-2)}
.langs li a[aria-current="page"]{font-weight:640}
.icon-btn{display:inline-grid;place-items:center;width:2.75rem;height:2.75rem;margin-right:-.6rem;background:none;border:0;color:var(--ink);cursor:pointer;border-radius:50%;flex:none}
@media (max-width:760px){.topnav{display:none}.topbar{gap:.6rem}}

/* ---- right rail ---- */
.rail{position:fixed;right:.9rem;top:50%;transform:translateY(-50%);z-index:30;display:flex;flex-direction:column;gap:.55rem}
.rail a{display:flex;align-items:center;justify-content:flex-end;gap:.5rem;text-decoration:none;color:var(--ink-2);font-size:.8rem;min-height:24px}
.rail a span{opacity:0;transform:translateX(6px);transition:opacity .2s,transform .2s;background:var(--card);padding:.1rem .45rem;border-radius:4px;border:1px solid var(--rule);white-space:nowrap}
.rail a:hover span,.rail a:focus-visible span{opacity:1;transform:none}
.rail i{width:8px;height:8px;border-radius:50%;border:1.5px solid var(--rule-2);flex:none;transition:background .2s,transform .2s}
.rail a[aria-current="true"] i{background:var(--accent);border-color:var(--accent);transform:scale(1.3)}
@media (max-width:1100px){.rail{display:none}}

/* ---- opening ---- */
.hero{position:relative;padding:0 0 2rem}
.hero-text{max-width:46rem;margin:0 auto;padding:3.2rem 1.25rem 1.2rem}
.kicker{font:500 .8rem/1.3 "Plex Mono",ui-monospace,monospace;letter-spacing:.08em;text-transform:uppercase;color:var(--accent);margin:0 0 1rem}
h1{font-size:clamp(2.3rem,6.2vw,4.4rem);line-height:1.02;letter-spacing:-.022em;font-weight:560;margin:0 0 1.1rem;text-wrap:balance}
h1 .second{display:block;font-style:italic;font-weight:400;color:var(--accent)}
.deck{font-size:1.32rem;line-height:1.5;color:var(--ink-2);margin:0;max-width:40rem}
.byline{font-size:.92rem;color:var(--ink-2);margin:1.2rem 0 0}

.city{margin:1.2rem auto 0;max-width:1400px;padding:0 1rem}
.city-frame{position:relative;aspect-ratio:16/9;background:var(--map-bg);border-radius:6px;overflow:hidden}
.city canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.city-year{position:absolute;left:1.1rem;top:.6rem;font:600 clamp(2.4rem,7vw,5.4rem)/1 "Newsreader",Georgia,serif;letter-spacing:-.03em;color:var(--ink);opacity:.9;pointer-events:none;font-variant-numeric:tabular-nums}
.city .status,.stage .status{position:absolute;inset:auto 0 45% 0;text-align:center;color:var(--ink-2);font-size:1rem;pointer-events:none}
.city-ctl{display:flex;align-items:center;gap:.8rem;flex-wrap:wrap;margin:.7rem 0 0;font-size:.95rem}
.city-ctl input{flex:1 1 14rem}
.city figcaption,.fig figcaption{font-size:.95rem;line-height:1.5;color:var(--ink-2);margin:.6rem 0 0;max-width:46rem}
@media (max-width:640px){.city-frame{aspect-ratio:4/5}}

button.btn,.play{font:inherit;font-size:.92rem;background:var(--card);color:var(--ink);border:1px solid var(--rule-2);border-radius:99px;padding:.4rem .95rem;min-height:44px;cursor:pointer}
button.btn[aria-pressed="true"]{background:var(--ink);color:var(--bg);border-color:var(--ink)}
input[type=range]{accent-color:var(--accent);min-height:44px}

.ramp{display:flex;align-items:center;gap:.5rem;font:400 .8rem/1 "Plex Mono",ui-monospace,monospace;color:var(--ink-2)}
.ramp i{display:block;width:9rem;height:.6rem;border-radius:2px;background:linear-gradient(90deg,var(--y0),var(--y1) 17%,var(--y2) 42%,var(--y3) 60%,var(--y4) 75%,var(--y5) 88%,var(--y6))}

/* ---- prose ---- */
main{display:block}
.block{max-width:44rem;margin:0 auto;padding:3.5rem 1.25rem 0}
.block h2{font-size:clamp(1.75rem,3.6vw,2.5rem);line-height:1.12;letter-spacing:-.015em;font-weight:560;margin:0 0 1.1rem;text-wrap:balance}
.block h3{font-size:1.25rem;margin:2rem 0 .5rem;font-weight:620}
.anchor{color:inherit;text-decoration:none}
.anchor:hover{text-decoration:underline;text-decoration-thickness:1px}
p{margin:0 0 1.05rem}
.wide{max-width:72rem;margin:2.2rem auto;padding:0 1.25rem}
.fig{margin:2rem 0}
.fig img{border-radius:4px;border:1px solid var(--rule);background:var(--bg-2)}
.fig .credit{display:block;font-size:.82rem;color:var(--ink-2);margin-top:.3rem}
.pair{display:grid;grid-template-columns:1.25fr 1fr;gap:1.4rem;align-items:start}
@media (max-width:760px){.pair{grid-template-columns:1fr}}
.zoomwrap{overflow:hidden;border-radius:4px}
.zoomed .zoomwrap{overflow:auto;max-height:78vh;-webkit-overflow-scrolling:touch}
.zoomed .zoomwrap img{max-width:none;width:auto}
.zoom{margin-top:.5rem}
.portrait{float:right;width:9.5rem;margin:.3rem 0 1rem 1.4rem}
.portrait img{border-radius:3px}
.portrait figcaption{font-size:.8rem;line-height:1.35;color:var(--ink-2);margin-top:.35rem}
@media (max-width:520px){.portrait{width:7.2rem;margin-left:1rem}}

.big{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem;margin:1.8rem 0}
.big div{border-top:2px solid var(--ink);padding-top:.6rem}
.big b{display:block;font-size:clamp(2rem,5vw,3rem);line-height:1;font-weight:560;letter-spacing:-.02em;font-variant-numeric:tabular-nums}
.big span{display:block;font-size:.95rem;line-height:1.4;color:var(--ink-2);margin-top:.35rem}
@media (max-width:640px){.big{grid-template-columns:1fr}}

/* ---- the 3D story ---- */
.story{position:relative;margin:3rem 0 0}
.stage{position:sticky;top:2.75rem;height:calc(100vh - 2.75rem);height:calc(100svh - 2.75rem);background:var(--g-fog);overflow:hidden;z-index:1}
.stage canvas{position:absolute;inset:0;width:100%;height:100%;display:block;touch-action:none;cursor:grab}
.stage canvas:active{cursor:grabbing}
.stage.failed canvas{display:none}
.stage .fallback{display:none;position:absolute;inset:0;padding:1rem}
.stage.failed .fallback{display:grid;place-items:center}
.stage .fallback img{max-height:100%;width:auto;margin:0 auto;border-radius:4px}
.hud{position:absolute;left:0;right:0;bottom:0;display:flex;gap:.6rem 1.2rem;flex-wrap:wrap;align-items:center;padding:.6rem 1rem .8rem;background:linear-gradient(transparent,var(--g-fog) 40%);font-size:.9rem;z-index:2}
.hud label{display:flex;align-items:center;gap:.5rem;flex:1 1 15rem;color:var(--ink)}
.hud label span.lab{white-space:nowrap;color:var(--ink-2)}
.hud output{font-family:"Plex Mono",ui-monospace,monospace;font-size:.85rem;min-width:7.5rem;white-space:nowrap}
.hud input{flex:1 1 auto;min-width:6rem}
.hud .modes{display:flex;gap:.4rem}
.legend-floors,.legend-years{display:flex;gap:.8rem;align-items:center;flex-wrap:wrap;font-size:.82rem;color:var(--ink-2)}
.sw{display:inline-block;width:.8rem;height:.8rem;border-radius:2px;vertical-align:-.1rem;margin-right:.3rem}
.sw-low{background:var(--g-low)}.sw-cut{background:var(--g-cut)}.sw-stone{background:var(--g-stone)}.sw-sel{background:var(--g-sel)}
.hint{position:absolute;right:1rem;top:.8rem;font-size:.82rem;color:var(--ink-2);background:var(--bar-bg);padding:.25rem .6rem;border-radius:4px;z-index:2;max-width:18rem}
.steps{position:relative;z-index:3;margin-top:-100vh;margin-top:-100svh;pointer-events:none}
.step{min-height:95vh;display:flex;align-items:center;padding:0 1.25rem}
.step:first-child{padding-top:30vh}
.step:last-child{min-height:60vh}
.card{pointer-events:auto;max-width:25rem;background:var(--card);border:1px solid var(--rule);border-radius:8px;padding:1.1rem 1.25rem;box-shadow:0 10px 30px rgba(0,0,0,.12);font-size:1.06rem;line-height:1.55;opacity:.55;transition:opacity .35s}
.step.on .card{opacity:1}
.card h3{margin:0 0 .5rem;font-size:1.2rem;line-height:1.25;font-weight:640}
.card p:last-child{margin-bottom:0}
.card .num{font-size:.95em}
@media (min-width:1000px){.step{padding-left:max(2rem,calc((100vw - 72rem)/2))}}
@media (max-width:760px){
  .stage{height:62vh;height:62svh;z-index:2}
  .steps{margin-top:0;z-index:1}
  .step{min-height:auto;padding:0 1rem 46vh;padding-bottom:46svh}
  .step:first-child{padding-top:1.2rem}
  .step:last-child{min-height:auto;padding-bottom:30svh}
  .card{max-width:none;opacity:1;box-shadow:0 6px 18px rgba(0,0,0,.14)}
  .hint{display:none}
  .hud{padding:.35rem .6rem .45rem;gap:.15rem .7rem;font-size:.78rem}
  .hud label{flex:1 1 40%;gap:.35rem}
  .hud label span.lab{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
  .hud output{min-width:0;font-size:.72rem}
  .hud input{min-width:3rem;min-height:36px}
  .hud .modes .btn{min-height:40px;padding:.2rem .75rem;font-size:.8rem}
  .legend-floors,.legend-years{font-size:.72rem;gap:.2rem .6rem}
}
.hud-live{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}

.blockpanel{position:absolute;right:1rem;top:3.2rem;width:17rem;background:var(--card);border:1px solid var(--rule);border-radius:8px;padding:.8rem .9rem;z-index:4;font-size:.88rem;box-shadow:0 10px 30px rgba(0,0,0,.15)}
.blockpanel h3{margin:0 1.8rem .4rem 0;font-size:1rem;line-height:1.25}
.bp-close{position:absolute;right:.2rem;top:.2rem;width:2.5rem;height:2.5rem;border:0;background:none;color:var(--ink);font-size:1.3rem;cursor:pointer;border-radius:50%}
.bp-facts{display:grid;grid-template-columns:1fr auto;gap:.1rem .6rem;margin:0 0 .6rem}
.bp-facts dt{color:var(--ink-2)}.bp-facts dd{margin:0;font-family:"Plex Mono",ui-monospace,monospace;font-size:.84rem;text-align:right}
.bp-bars{display:grid;gap:2px}
.bp-row{display:grid;grid-template-columns:2.6rem 1fr 2.8rem;gap:.4rem;align-items:center;font-size:.76rem;color:var(--ink-2)}
.bp-row i{display:block;height:.55rem;background:var(--g-stone);border-radius:1px}
.bp-row:first-child i{background:var(--g-low)}
.bp-row b{font-weight:400;font-family:"Plex Mono",ui-monospace,monospace;text-align:right}
.bp-cap{font-size:.78rem;color:var(--ink-2);margin:.2rem 0 .3rem}
.w0{width:0}.w5{width:5%}.w10{width:10%}.w15{width:15%}.w20{width:20%}.w25{width:25%}.w30{width:30%}.w35{width:35%}.w40{width:40%}.w45{width:45%}.w50{width:50%}.w55{width:55%}.w60{width:60%}.w65{width:65%}.w70{width:70%}.w75{width:75%}.w80{width:80%}.w85{width:85%}.w90{width:90%}.w95{width:95%}.w100{width:100%}
@media (max-width:760px){.blockpanel{position:fixed;left:.6rem;right:.6rem;top:auto;bottom:.6rem;width:auto;max-height:55vh;overflow:auto;z-index:45}}

/* ---- charts ---- */
.chart{width:100%;height:auto;display:block;overflow:visible}
.chart text{fill:var(--ink-2);font:400 13px "Plex Mono",ui-monospace,monospace}
.chart .t-strong{fill:var(--ink);font-weight:600}
.chart .bar{fill:var(--g-stone)}
.chart .bar.low{fill:var(--g-low)}
.chart .bar.dec{fill:var(--rule-2)}
.chart .bar.hot{fill:var(--accent)}
.chart .axis{stroke:var(--rule-2);stroke-width:1}
.chart .ann{fill:var(--ink);font-family:"Newsreader",Georgia,serif;font-size:15px}
.chart-cap{font-size:.95rem;color:var(--ink-2);margin:.4rem 0 0}

/* ---- rules timeline ---- */
.rules{list-style:none;margin:1.6rem 0;padding:0;border-left:2px solid var(--rule-2)}
.rules li{position:relative;padding:0 0 1.2rem 1.3rem}
.rules li::before{content:"";position:absolute;left:-7px;top:.45rem;width:12px;height:12px;border-radius:50%;background:var(--bg);border:2px solid var(--accent)}
.rules .yr{display:block;font:600 .95rem/1.3 "Plex Mono",ui-monospace,monospace;color:var(--accent)}
.rules p{margin:.15rem 0 0}

/* ---- sources ---- */
.method{font-size:1.02rem}
.srcs{padding-left:1.1rem;font-size:.95rem}
.srcs li{margin:.35rem 0}
.foot{max-width:44rem;margin:4rem auto 0;padding:1.5rem 1.25rem 3rem;border-top:1px solid var(--rule);font-size:.9rem;color:var(--ink-2)}
.foot p{margin:.3rem 0}
.foot a{color:var(--ink-2)}
.nf{display:grid;place-items:center;min-height:100vh;text-align:center}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.city-static{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.city.ready .city-static{display:none}
html:not(.js) .city canvas,html:not(.js) .city-ctl,html:not(.js) .city-year{display:none}
html:not(.js) .stage canvas,html:not(.js) .hud,html:not(.js) .hint{display:none}
html:not(.js) .stage .fallback{display:grid;place-items:center}
@media (max-width:760px){.stage.in-story .hud{display:none}}
.seq{list-style:none;margin:.8rem 0 1.2rem;padding:0;display:grid;grid-template-columns:repeat(3,1fr);gap:.8rem}
.seq li{border-top:3px solid var(--accent);padding-top:.5rem;font-size:1rem;line-height:1.45}
.seq .yr{display:block;font:600 1.5rem/1.1 "Newsreader",Georgia,serif;color:var(--accent);margin-bottom:.2rem}
@media (max-width:640px){.seq{grid-template-columns:1fr}}
.bp-garden{margin:.1rem 0 .5rem;font-size:.82rem;color:var(--green);font-weight:600}
.sw-garden{background:var(--g-garden)}