:root {
  --night: #0a0e15;
  --stone: #121821;
  --stone-2: #1a222d;
  --rule: #263140;
  --mist: #8d9fb3;
  --steel: #c7ced8;
  --paper: #eef1f5;
  --ember: #ff6b1f;
  --ember-glow: rgba(255, 107, 31, 0.45);

  --serif: "Cormorant Garamond", "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  --sans: "Hanken Grotesk", "Segoe UI", system-ui, sans-serif;

  --step--1: 0.875rem;
  --step-0: 1.0625rem;
  --step-1: 1.25rem;
  --step-2: clamp(1.6rem, 1.2rem + 1.4vw, 2.1rem);
  --step-3: clamp(2.3rem, 1.5rem + 3vw, 3.6rem);
  --step-4: clamp(3.1rem, 1.4rem + 6vw, 6.6rem);

  --gutter: clamp(1rem, 4vw, 3.5rem);
  --measure: 36rem;
  color-scheme: dark;
}

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

html { scroll-behavior: smooth; scroll-padding-top: 5rem; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--night);
  color: var(--steel);
  font: 400 var(--step-0) / 1.6 var(--sans);
  font-feature-settings: "tnum" 0;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, video, canvas { display: block; max-width: 100%; }
h1, h2, h3 { color: var(--paper); margin: 0; font-weight: 500; }
h1, h2 { font-family: var(--serif); letter-spacing: -0.01em; }
h2 { font-size: var(--step-3); line-height: 1.02; }
h3 { font: 600 var(--step-0) / 1.3 var(--sans); }
p { margin: 0; }
a { color: inherit; }
code { font: 0.92em ui-monospace, "Cascadia Code", Consolas, monospace; color: var(--paper); }
sub { font-size: 0.62em; }
output { font-variant-numeric: tabular-nums; }

:focus-visible { outline: 2px solid var(--ember); outline-offset: 3px; border-radius: 2px; }

.sr {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap;
}

.skip {
  position: absolute; left: var(--gutter); top: -3rem; z-index: 20;
  background: var(--paper); color: var(--night); padding: 0.5rem 0.9rem;
}
.skip:focus { top: 1rem; }

/* Buttons */
.button {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 3rem; padding: 0 1.4rem;
  font: 500 var(--step-0) / 1 var(--sans);
  text-decoration: none; cursor: pointer;
  border: 1px solid transparent; border-radius: 999px;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s;
}
.button--ember { background: var(--ember); color: #1b0a02; box-shadow: 0 0 32px -6px var(--ember-glow); }
.button--ember:hover { background: #ff8440; }
.button--ghost { border-color: rgba(199, 206, 216, 0.35); color: var(--paper); background: rgba(10, 14, 21, 0.35); }
.button--ghost:hover { border-color: var(--paper); }
.button--small { min-height: 2.6rem; padding: 0 1.1rem; font-size: var(--step--1); }
.link-button {
  background: none; border: 0; padding: 0.4rem 0; cursor: pointer;
  color: var(--mist); font: inherit; font-size: var(--step--1);
  text-decoration: underline; text-underline-offset: 3px;
}
.link-button:hover { color: var(--paper); }

/* Nav */
.nav {
  position: absolute; inset: 0 0 auto; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  padding: 1.25rem var(--gutter);
}
.nav-home {
  display: flex; align-items: center; gap: 0.6rem; text-decoration: none;
  font: 600 1.55rem / 1 var(--serif); color: var(--paper);
}
.nav-home img { border-radius: 8px; }
.nav nav { display: flex; gap: clamp(0.9rem, 2.4vw, 2rem); font-size: var(--step--1); }
.nav nav a { text-decoration: none; color: var(--steel); }
.nav nav a:hover { color: var(--paper); }
.nav-spec { border-bottom: 1px solid var(--ember); }
.nav nav { align-items: center; }
.nav nav .nav-app { padding: 0.5rem 1rem; border-radius: 999px; background: var(--ember); color: #1b0a02; font-weight: 500; }
.nav nav .nav-app:hover { background: #ff8440; color: #1b0a02; }
@media (max-width: 720px) { .nav nav a:not(.nav-spec):not(.nav-app) { display: none; } }

/* Hero */
.hero {
  position: relative; isolation: isolate; overflow: hidden;
  min-height: max(100svh, 44rem);
  display: grid; grid-template-rows: 1fr auto;
  padding: 6.5rem var(--gutter) 0;
}
.stage { position: absolute; inset: 0; z-index: -1; background: var(--night); }
.stage-light {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 22% 55% at 64% -8%, rgba(190, 212, 240, 0.34), transparent 70%),
    radial-gradient(ellipse 60% 40% at 64% 0%, rgba(120, 150, 190, 0.16), transparent 75%),
    linear-gradient(to bottom, transparent 62%, rgba(40, 52, 68, 0.55) 86%, rgba(12, 16, 23, 1));
}
.stage-video {
  position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover;
  opacity: 0.9;
}
.stage-mist {
  position: absolute; inset: 0;
  background:
    linear-gradient(90deg, rgba(10, 14, 21, 0.85) 0%, rgba(10, 14, 21, 0.35) 45%, transparent 70%),
    linear-gradient(to top, var(--night) 0%, transparent 38%);
}

.hero-copy { align-self: center; max-width: 44rem; padding-block: 2rem; }
.hero h1 {
  font-size: var(--step-4); line-height: 0.9; letter-spacing: -0.025em;
  text-wrap: balance; max-width: 12ch;
}
.lede { margin-top: 1.6rem; max-width: 33rem; font-size: var(--step-1); line-height: 1.55; color: var(--steel); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2.2rem; }

.ticker { margin: 0 calc(var(--gutter) * -1); position: relative; }
#hero-chart { width: 100%; height: clamp(10rem, 27vh, 18rem); }
.ticker-readouts {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.6rem clamp(1.5rem, 4vw, 3.5rem);
  padding: 1.1rem var(--gutter) 1.6rem;
  border-top: 1px solid rgba(255, 107, 31, 0.28);
  background: linear-gradient(to bottom, rgba(18, 24, 33, 0.9), var(--night));
  color: var(--mist); font-size: var(--step--1);
}
.ticker-readouts div { display: flex; align-items: baseline; gap: 0.45rem; }
.ticker-readouts output { font: 500 var(--step-1) / 1 var(--sans); color: var(--paper); }
.ticker-readouts div:first-child output { color: var(--ember); }
.ticker-note { margin-left: auto; font-size: 0.8rem; color: #66778a; }
@media (max-width: 720px) { .ticker-note { margin-left: 0; flex-basis: 100%; } }

/* How */
section { padding: clamp(5rem, 11vw, 9rem) var(--gutter); }

.how {
  display: grid; gap: clamp(3rem, 7vw, 7rem);
  grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  max-width: 88rem; margin-inline: auto;
}
.how-intro { align-self: start; position: sticky; top: 3rem; }
.how-intro > p { margin-top: 1.4rem; max-width: var(--measure); }
.formula {
  display: flex; align-items: center; gap: 1.1rem; margin-top: 2.6rem;
  font: italic 500 clamp(3rem, 2rem + 4vw, 5rem) / 1 var(--serif); color: var(--paper);
}
.formula-eq { font-style: normal; color: var(--mist); }
.formula-frac { display: inline-grid; text-align: center; }
.formula-frac span:first-child { border-bottom: 2px solid var(--ember); padding: 0 0.3em 0.06em; box-shadow: 0 10px 18px -12px var(--ember-glow); }
.formula-frac span:last-child { padding-top: 0.08em; }
.legend { margin: 2rem 0 0; display: grid; gap: 0.7rem; max-width: var(--measure); font-size: var(--step--1); }
.legend div { display: grid; grid-template-columns: 2.4rem 1fr; }
.legend dt { font: italic 500 1.35rem / 1.1 var(--serif); color: var(--paper); }
.legend dd { margin: 0; color: var(--mist); }

.flows { display: grid; }
.flow { padding: 2.2rem 0; border-top: 1px solid var(--rule); }
.flow:last-child { border-bottom: 1px solid var(--rule); }
.flow h3 { font: 500 var(--step-2) / 1.1 var(--serif); }
.flow p { margin-top: 0.8rem; max-width: var(--measure); }
.flow .math {
  margin-top: 1.1rem; display: inline-block;
  font: italic 500 1.3rem / 1.4 var(--serif); color: var(--paper);
  padding-left: 0.9rem; border-left: 2px solid var(--ember);
}

@media (max-width: 900px) {
  .how { grid-template-columns: 1fr; }
  .how-intro { position: static; }
}

/* Cycle */
.cycle {
  display: grid; gap: clamp(2.5rem, 6vw, 6rem); align-items: center;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  max-width: 88rem; margin-inline: auto;
}
.cycle-copy > p:first-of-type { margin-top: 1.4rem; max-width: var(--measure); }
.steps { counter-reset: step; list-style: none; padding: 0; margin: 2rem 0 0; display: grid; gap: 0.9rem; max-width: var(--measure); }
.steps li { counter-increment: step; display: grid; grid-template-columns: 2.2rem 1fr; }
.steps li::before {
  content: counter(step); font: 600 1.35rem / 1.2 var(--serif); color: var(--ember);
}
.aside { margin-top: 2rem; max-width: var(--measure); color: var(--mist); font-size: var(--step--1); }
.cycle-figure { margin: 0; }
.cycle-figure img { width: 100%; height: auto; border-radius: 6px; }
@media (max-width: 900px) { .cycle { grid-template-columns: 1fr; } .cycle-figure { order: -1; } }

/* Simulator */
.try { background: linear-gradient(to bottom, var(--night), var(--stone) 12%, var(--stone) 88%, var(--night)); }
.try-head, .sim { max-width: 88rem; margin-inline: auto; }
.try-head p { margin-top: 1.2rem; max-width: 40rem; }

.sim {
  margin-top: 3rem;
  display: grid; gap: 1.5rem;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  grid-template-areas: "board controls" "history controls";
}
.sim-board, .sim-controls, .sim-history { background: var(--night); border: 1px solid var(--rule); border-radius: 14px; }
.sim-board { grid-area: board; padding: clamp(1.25rem, 3vw, 2rem); }
.sim-controls { grid-area: controls; padding: 0.4rem clamp(1.25rem, 3vw, 1.8rem) 1.4rem; align-self: start; }
.sim-history { grid-area: history; padding: clamp(1.25rem, 3vw, 2rem); }

.sim-floor { display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.3rem 0.8rem; color: var(--mist); font-size: var(--step--1); }
.sim-floor > span:first-child { flex-basis: 100%; }
.sim-floor output {
  font: 500 clamp(2.4rem, 1.4rem + 4vw, 4.2rem) / 1 var(--sans); letter-spacing: -0.02em;
  color: var(--ember); text-shadow: 0 0 28px var(--ember-glow);
}
.sim-delta { color: var(--paper); font-weight: 500; font-variant-numeric: tabular-nums; }
.sim-delta.is-new { animation: pulse 1.1s ease-out; }
@keyframes pulse { from { color: var(--ember); } to { color: var(--paper); } }

.sim-stats {
  margin: 1.6rem 0 0; display: grid; gap: 1rem 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
}
.sim-stats dt { font-size: 0.8rem; color: var(--mist); }
.sim-stats dd { margin: 0.15rem 0 0; color: var(--paper); font-variant-numeric: tabular-nums; }
#sim-chart { width: 100%; height: 11rem; margin-top: 1.6rem; }

.action { padding: 1.3rem 0; border-bottom: 1px solid var(--rule); }
.action h3 { font-size: var(--step-0); }
.action p { margin-top: 0.3rem; font-size: var(--step--1); color: var(--mist); line-height: 1.5; }
.action-input { display: flex; gap: 0.6rem; margin-top: 0.9rem; }
.field {
  flex: 1; display: flex; align-items: center; min-width: 0;
  border: 1px solid var(--rule); border-radius: 999px; background: var(--stone);
  padding: 0 1rem;
}
.field:focus-within { border-color: var(--ember); }
.field input {
  flex: 1; min-width: 0; background: none; border: 0; outline: 0;
  color: var(--paper); font: 500 var(--step-0) / 1 var(--sans); font-variant-numeric: tabular-nums;
  padding: 0.7rem 0;
}
.field span { color: var(--mist); font-size: 0.8rem; }
.action .button { background: var(--paper); color: var(--night); }
.action .button:hover { background: #fff; }

.sim-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.2rem; padding-top: 1.3rem; }
.beta { flex-basis: 100%; display: grid; gap: 0.5rem; font-size: var(--step--1); color: var(--mist); }
.beta output { color: var(--paper); margin-left: 0.3rem; }
.beta input { accent-color: var(--ember); width: 100%; }
.form-error { margin-top: 1rem; color: #ffb38a; font-size: var(--step--1); }

.verdict { font: 500 var(--step-2) / 1.2 var(--serif); color: var(--paper); max-width: 34rem; }
.log { list-style: none; padding: 0; margin: 1.4rem 0 0; display: grid; gap: 0; max-height: 26rem; overflow-y: auto; }
.log li { padding: 1rem 0; border-top: 1px solid var(--rule); font-size: var(--step--1); }
.log .log-what { color: var(--paper); }
.log .log-math { margin-top: 0.35rem; font: italic 500 1.08rem / 1.4 var(--serif); color: var(--mist); overflow-wrap: anywhere; }
.log .log-floor { margin-top: 0.3rem; font-variant-numeric: tabular-nums; }
.log .log-floor b { color: var(--ember); font-weight: 600; }

@media (max-width: 960px) {
  .sim { grid-template-columns: minmax(0, 1fr); grid-template-areas: "board" "controls" "history"; }
}

/* Stories */
.stories { display: grid; gap: clamp(4rem, 10vw, 8rem); max-width: 80rem; margin-inline: auto; }
.story { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); gap: clamp(2rem, 6vw, 6rem); align-items: center; }
.story img { width: 100%; height: auto; aspect-ratio: 4 / 5; object-fit: cover; border-radius: 6px; }
.story--flip img { order: 2; }
.stories:has(.no-media) { grid-template-columns: repeat(auto-fit, minmax(min(100%, 22rem), 1fr)); gap: 3rem clamp(2rem, 6vw, 6rem); }
.story.no-media { grid-template-columns: minmax(0, 1fr); align-items: start; }
.story.no-media .story-copy { padding-left: 1.5rem; border-left: 2px solid var(--ember); }
.story-copy p { margin-top: 1.1rem; max-width: var(--measure); }
.story-copy h2 { max-width: 14ch; }
@media (max-width: 800px) {
  .story { grid-template-columns: 1fr; }
  .story--flip img { order: 0; }
  .story img { aspect-ratio: 16 / 10; }
}

/* Parameters */
.params { max-width: 72rem; margin-inline: auto; }
.params-head p { margin-top: 1rem; max-width: var(--measure); }
.table-wrap { margin-top: 2.5rem; overflow-x: auto; }
table { width: 100%; border-collapse: collapse; font-variant-numeric: tabular-nums; }
th { text-align: left; font-weight: 500; font-size: 0.8rem; color: var(--mist); padding: 0 1rem 0.8rem 0; }
td { padding: 0.95rem 1rem 0.95rem 0; border-top: 1px solid var(--rule); vertical-align: baseline; }
td:first-child { font: italic 500 1.3rem / 1 var(--serif); color: var(--paper); white-space: nowrap; }
td:last-child { color: var(--paper); white-space: nowrap; text-align: right; padding-right: 0; }
th:last-child { text-align: right; padding-right: 0; }

/* Lean */
.lean { position: relative; isolation: isolate; min-height: 38rem; display: grid; align-items: end; overflow: hidden; }
.lean-image { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: -2; }
.lean::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background:
    linear-gradient(90deg, rgba(10, 14, 21, 0.92) 0%, rgba(10, 14, 21, 0.7) 38%, rgba(10, 14, 21, 0) 65%),
    linear-gradient(to bottom, var(--night), rgba(10, 14, 21, 0.2) 40%, rgba(10, 14, 21, 0.9));
}
.lean.no-media {
  background:
    radial-gradient(ellipse 30% 70% at 70% 0%, rgba(160, 185, 215, 0.2), transparent 70%),
    linear-gradient(to bottom, transparent 86%, rgba(255, 107, 31, 0.5) 86.15%, rgba(26, 34, 45, 1) 86.5%, var(--night));
}
.lean.no-media .lean-copy { padding-bottom: 5rem; }
.lean-copy { max-width: 40rem; }
.lean-copy p { margin: 1.2rem 0 2rem; }

/* Footer */
.footer {
  display: grid; grid-template-columns: auto 1fr auto; gap: 1.5rem 2rem; align-items: center;
  padding: 3rem var(--gutter); border-top: 1px solid var(--rule); font-size: var(--step--1); color: var(--mist);
}
.footer img { border-radius: 10px; }
.footer p { max-width: 34rem; }
.footer nav { display: flex; gap: 1.5rem; }
.footer nav a { text-decoration: none; }
.footer nav a:hover { color: var(--paper); }
@media (max-width: 720px) { .footer { grid-template-columns: 1fr; } }

/* Spec page */
.spec-page { display: grid; grid-template-columns: 16rem minmax(0, 46rem); gap: clamp(2rem, 6vw, 6rem); justify-content: center; padding: 8rem var(--gutter) 6rem; }
.spec-toc { position: sticky; top: 2rem; align-self: start; font-size: var(--step--1); }
.spec-toc ol { list-style: none; padding: 0; margin: 1rem 0 0; display: grid; gap: 0.45rem; }
.spec-toc a { text-decoration: none; color: var(--mist); }
.spec-toc a:hover { color: var(--paper); }
.spec h1 { font-size: var(--step-3); line-height: 1; }
.spec .spec-sub { margin-top: 0.8rem; color: var(--mist); }
.spec section { padding: 0; margin-top: 4rem; }
.spec h2 { font-size: var(--step-2); display: flex; gap: 0.8rem; align-items: baseline; }
.spec h2 .n { color: var(--ember); font-size: 0.8em; }
.spec h3 { margin-top: 2rem; }
.spec p, .spec ul, .spec ol, .spec pre, .spec .table-wrap { margin-top: 1rem; }
.spec ul, .spec ol { padding-left: 1.2rem; }
.spec li + li { margin-top: 0.4rem; }
.spec pre {
  background: var(--stone); border: 1px solid var(--rule); border-radius: 8px; padding: 1rem 1.2rem;
  overflow-x: auto; font: 0.92rem / 1.6 ui-monospace, "Cascadia Code", Consolas, monospace; color: var(--paper);
}
.spec .eq { font: italic 500 1.35rem / 1.5 var(--serif); color: var(--paper); padding-left: 1rem; border-left: 2px solid var(--ember); }
.spec strong { color: var(--paper); font-weight: 600; }
.spec td:first-child { font: 500 var(--step--1) / 1.4 var(--sans); font-style: normal; white-space: normal; }
@media (max-width: 900px) { .spec-page { grid-template-columns: 1fr; } .spec-toc { position: static; } }