/* ============================================================
   The First Use Case — editorial scrollytelling system
   Register: editorial serif discipline, Miami Vice palette.
   Fraunces (titles) / Inter (body) / JetBrains Mono (figures).
   Dark is the default; light is the toggle. Series colors are
   validated with the dataviz six-checks validator on both
   surfaces (CVD warn-band covered by direct labels everywhere).
   ============================================================ */

:root {
  /* night in Miami — the default */
  --ink: #f6efff;
  --paper: #120b33;
  --ink-muted: color-mix(in oklab, var(--ink) 64%, var(--paper) 36%);
  --ink-faint: color-mix(in oklab, var(--ink) 40%, var(--paper) 60%);
  --accent: #ff3d9e;           /* the one earned accent: hot pink */
  --olive-gold: var(--accent); /* legacy alias used across the page */
  --accent-2: #23c6d8;         /* neon cyan — charts + hero only */
  --hairline: rgba(246, 239, 255, 0.12);
  --paper-wash: rgba(18, 11, 51, 0.86);

  /* chart series (validated on #120b33) */
  --series-human: #0fa8b8;     /* the old way: cool cyan */
  --series-machine: #f2308f;   /* the new way: vice pink */
  --chart-grid: rgba(246, 239, 255, 0.09);
  --chart-axis: rgba(246, 239, 255, 0.32);

  /* hero ascii buckets */
  --hero-dim: #453579;
  --hero-mid: #23c6d8;
  --hero-hot: #ff3d9e;
  --hero-top: #ffd9ec;

  --font-serif: "Fraunces", "Iowan Old Style", Georgia, serif;
  --font-sans: "Inter", -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", monospace;

  --measure: 34rem;
  --measure-wide: 44rem;
}

:root[data-theme="light"] {
  /* Miami at noon — pastel deco */
  --ink: #26123f;
  --paper: #fdf5ef;
  --accent: #d6207f;
  --accent-2: #128fa0;
  --hairline: rgba(38, 18, 63, 0.12);
  --paper-wash: rgba(253, 245, 239, 0.9);
  --series-human: #128fa0;
  --series-machine: #d6207f;
  --chart-grid: rgba(38, 18, 63, 0.08);
  --chart-axis: rgba(38, 18, 63, 0.32);
  --hero-dim: #e3d4f2;
  --hero-mid: #128fa0;
  --hero-hot: #d6207f;
  --hero-top: #26123f;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: auto; }

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection { background: color-mix(in oklab, var(--accent) 40%, var(--paper) 60%); }

a {
  color: inherit;
  text-decoration: underline;
  text-decoration-color: transparent;
  text-underline-offset: 4px;
  transition: text-decoration-color 0.2s ease;
}
a:hover, a:focus-visible { text-decoration-color: var(--accent); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- progress hairline ---------- */
.progress {
  position: fixed; top: 0; left: 0; height: 2px; width: 100%;
  z-index: 50; pointer-events: none;
  background: transparent;
}
.progress > i {
  display: block; height: 100%; width: 100%;
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  transform-origin: 0 50%; transform: scaleX(0);
}

/* ---------- theme toggle ---------- */
.theme-toggle {
  position: fixed; top: 14px; right: 18px; z-index: 60;
  display: flex; gap: 0.6rem; align-items: baseline;
  background: var(--paper-wash);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--hairline); cursor: pointer;
  font-family: var(--font-sans);
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--ink-muted);
  padding: 6px 8px;
}
.theme-toggle span { transition: color 0.15s ease; }
.theme-toggle span.on { color: var(--accent); }
.theme-toggle i { font-style: normal; color: var(--ink-faint); }

/* ---------- masthead (sticky ascii opener) ---------- */
.masthead {
  position: relative;
  min-height: var(--h, 230svh);
}
.masthead-sticky {
  position: sticky; top: 0;
  height: 100svh;
  overflow: hidden;
  display: grid;
  grid-template-rows: auto 1fr auto;
  padding: 24px;
}
.masthead-canvas {
  position: absolute; inset: 0; z-index: 0;
  width: 100%; height: 100%;
}
.masthead-top {
  position: relative; z-index: 2;
  display: flex; justify-content: flex-start; gap: 0.75rem; align-items: baseline;
  font-family: var(--font-sans);
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--ink);
}
.masthead-top span {
  background: var(--paper-wash);
  border: 1px solid var(--hairline);
  padding: 6px 10px;
}
.masthead-center {
  position: relative; z-index: 2;
  display: flex; flex-direction: column;
  justify-content: center; align-items: center;
  text-align: center;
  pointer-events: none;
}
.masthead-title {
  display: flex; flex-direction: column; align-items: center; gap: 1.5rem;
  background: var(--paper-wash);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--hairline);
  padding: 2.5rem 3rem;
  opacity: 0;
  transform: translateY(18px);
  will-change: opacity, transform;
  pointer-events: auto;
}
.masthead-eyebrow {
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--accent);
}
.masthead h1 {
  font-family: var(--font-serif);
  font-size: clamp(2.5rem, 7vw, 5rem);
  font-weight: 600;
  font-variation-settings: "opsz" 144;
  letter-spacing: -0.02em;
  line-height: 1.05;
  max-width: 16ch;
}
.masthead-dek {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: clamp(1.05rem, 2.2vw, 1.3rem);
  color: var(--ink-muted);
  max-width: 44ch;
  line-height: 1.5;
}
.masthead-byline {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  color: var(--ink-muted);
  letter-spacing: 0.02em;
}
.masthead-byline strong { color: var(--ink); font-weight: 600; }
.masthead-bottom {
  position: relative; z-index: 2;
  display: flex; justify-content: center;
  padding-bottom: 0.5rem;
}
.scroll-cue {
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.3em;
  color: var(--ink);
  background: var(--paper-wash);
  border: 1px solid var(--hairline);
  padding: 8px 14px 8px 18px;
  animation: cue 2.4s ease-in-out infinite;
}
@keyframes cue { 0%,100% { transform: translateY(0); opacity: .75; } 50% { transform: translateY(6px); opacity: 1; } }

/* ---------- prose blocks ---------- */
.prose {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 6rem 24px;
}
.prose > * + * { margin-top: 1.5rem; }
.prose p {
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.75;
}
.prose .lede::first-letter {
  font-family: var(--font-serif);
  font-size: 3.4em;
  line-height: 0.85;
  float: left;
  padding-right: 0.12em;
  padding-top: 0.06em;
  font-weight: 600;
  color: var(--accent);
}
.prose em { font-style: normal; font-weight: 600; }
.prose .aside {
  font-family: var(--font-serif); font-style: italic;
  color: var(--ink-muted);
}

.section-head {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 5rem 24px 0;
}
.section-head .rule { border-top: 1px solid var(--hairline); padding-top: 2rem; }
.section-head .eyebrow {
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--accent);
}
.section-head h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3.4vw, 2.25rem);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.015em;
  margin-top: 0.75rem;
  max-width: 24ch;
}
.section-head .dek {
  font-family: var(--font-serif); font-style: italic;
  font-size: 1.0625rem;
  color: var(--ink-muted);
  margin-top: 0.75rem;
  max-width: 40ch;
}

/* pull quote */
.pull {
  max-width: var(--measure-wide);
  margin: 0 auto;
  padding: 4rem 24px;
  text-align: center;
}
.pull blockquote {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3.6vw, 2.4rem);
  font-weight: 400;
  line-height: 1.3;
  letter-spacing: -0.01em;
  max-width: 28ch;
  margin: 0 auto;
}
.pull blockquote .gold { color: var(--accent); }
.pull cite {
  display: block;
  margin-top: 1.25rem;
  font-family: var(--font-sans);
  font-style: normal;
  font-size: 0.8125rem;
  color: var(--ink-muted);
}

/* ---------- scrollytelling scenes ---------- */
.scene {
  position: relative;
  min-height: var(--h, 400vh);
}
.scene-visual {
  position: sticky;
  top: 0;
  height: 100svh;
  overflow: hidden;
  z-index: 1;
}
.scene-visual canvas { display: block; width: 100%; height: 100%; }
.scene-steps {
  position: relative;
  z-index: 2;
  pointer-events: none;
  margin-top: -100svh;
}
.step {
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding: 0 24px;
}
.step[data-align="left"]    { justify-content: flex-start; }
.step[data-align="center"]  { justify-content: center; }
.step[data-align="right"]   { justify-content: flex-end; }
.step[data-align="bottom"]  { align-items: flex-end; justify-content: center; padding-bottom: 10svh; }
.step-card {
  max-width: 30rem;
  background: var(--paper-wash);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--accent);
  padding: 1.5rem 1.75rem;
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  pointer-events: auto;
}
.step.is-active .step-card { opacity: 1; transform: translateY(0); }
.step-card p {
  font-family: var(--font-sans);
  font-size: clamp(1rem, 1.9vw, 1.125rem);
  line-height: 1.65;
}
.step-card p + p { margin-top: 0.9rem; }
.step-card .kicker {
  display: block;
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--accent);
  margin-bottom: 0.6rem;
}
.step-card .figure {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(1.9rem, 4.5vw, 2.9rem);
  line-height: 1.1;
  letter-spacing: -0.015em;
  display: block;
  margin: 0.35rem 0;
}
.step-card .figure.gold { color: var(--accent); }
.step-card .fine {
  font-size: 0.8125rem;
  color: var(--ink-muted);
  line-height: 1.55;
}
.step-card strong { font-weight: 600; }

/* ---------- inline figures (article charts) ---------- */
.figure-block {
  max-width: var(--measure-wide);
  margin: 3.5rem auto;
  padding: 0 24px;
}
.figure-block .fig-title {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 600;
}
.figure-block .fig-dek {
  font-family: var(--font-serif); font-style: italic;
  font-size: 0.9375rem;
  color: var(--ink-muted);
  margin-top: 0.2rem;
}
.figure-block .fig-body { margin-top: 1.25rem; position: relative; }
.figure-block .fig-note {
  margin-top: 0.9rem;
  font-size: 0.8125rem;
  color: var(--ink-muted);
  line-height: 1.55;
  max-width: 56ch;
}
.figure-block .fig-note a { text-decoration-color: var(--hairline); }

.fig-body text {
  font-family: var(--font-sans);
  fill: var(--ink-muted);
  font-size: 11px;
}
.fig-body .tick-num { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

/* tooltip */
.viz-tip {
  position: fixed;
  z-index: 60;
  pointer-events: none;
  background: var(--paper);
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--accent);
  padding: 0.5rem 0.75rem;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--ink);
  max-width: 240px;
  opacity: 0;
  transition: opacity 0.15s ease;
}
.viz-tip .tip-label { color: var(--ink-muted); }
.viz-tip .tip-value { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.viz-tip.on { opacity: 1; }

/* legend */
.fig-legend {
  display: flex; flex-wrap: wrap; gap: 1.25rem;
  margin-top: 0.9rem;
  font-size: 0.8125rem;
  color: var(--ink-muted);
}
.fig-legend .key { display: inline-flex; align-items: center; gap: 0.45rem; }
.fig-legend .swatch { width: 14px; height: 3px; display: inline-block; }

/* ---------- the ledger (two-column compare) ---------- */
.ledger {
  max-width: var(--measure-wide);
  margin: 3rem auto;
  padding: 0 24px;
}
.ledger table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}
.ledger th {
  font-family: var(--font-sans);
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--ink-muted);
  text-align: left;
  padding: 0.6rem 0.5rem;
  border-bottom: 1px solid var(--chart-axis);
}
.ledger td {
  padding: 0.7rem 0.5rem;
  border-bottom: 1px solid var(--hairline);
  vertical-align: baseline;
}
.ledger td.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.ledger td.gold { color: var(--accent); font-weight: 500; }
.ledger .row-label { color: var(--ink-muted); }

/* ---------- coda ---------- */
.coda {
  min-height: 90svh;
  display: flex; flex-direction: column;
  justify-content: center; align-items: center;
  text-align: center;
  padding: 6rem 24px;
  gap: 2rem;
}
.coda h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.9rem, 5vw, 3.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
  max-width: 20ch;
}
.coda .coda-q {
  font-family: var(--font-serif); font-style: italic;
  font-size: clamp(1.1rem, 2.4vw, 1.4rem);
  color: var(--ink-muted);
  max-width: 40ch;
  line-height: 1.5;
}
.coda-form {
  display: flex; flex-direction: column; align-items: center; gap: 1rem;
  width: min(30rem, 100%);
}
.coda-form label { width: 100%; text-align: left; }
.coda-form label span {
  display: block;
  font-size: 0.6875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--ink-muted);
  margin-bottom: 0.4rem;
}
.coda-form input {
  width: 100%;
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--chart-axis);
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--ink);
  padding: 0.4rem 0;
  outline: none;
  text-align: center;
}
.coda-form input:focus { border-bottom-color: var(--accent); }
.coda-answer {
  font-family: var(--font-serif);
  font-size: clamp(1.4rem, 3.2vw, 2rem);
  line-height: 1.35;
  max-width: 26ch;
  min-height: 3em;
}
.coda-answer .gold { color: var(--accent); }

/* ---------- receipts appendix ---------- */
.receipts {
  max-width: var(--measure-wide);
  margin: 0 auto;
  padding: 4rem 24px 8rem;
}
.receipts summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 600;
  padding: 1.1rem 0;
  border-top: 1px solid var(--hairline);
  display: flex; justify-content: space-between; align-items: baseline;
}
.receipts summary::-webkit-details-marker { display: none; }
.receipts summary .aff {
  font-family: var(--font-sans);
  font-size: 0.6875rem; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--ink-muted);
}
.receipts details[open] summary .aff { color: var(--accent); }
.receipts .r-body {
  padding: 0 0 1.75rem;
  font-size: 0.9375rem;
  color: var(--ink);
  line-height: 1.7;
  max-width: 60ch;
}
.receipts .r-body p + p { margin-top: 0.8rem; }
.receipts .r-body .mono { font-family: var(--font-mono); font-size: 0.85em; }
.receipts .r-body ul { padding-left: 1.1rem; }
.receipts .r-body li { margin-top: 0.4rem; }

.footer {
  border-top: 1px solid var(--hairline);
  padding: 2.5rem 24px 4rem;
  text-align: center;
  font-size: 0.8125rem;
  color: var(--ink-muted);
}

/* ---------- responsive ---------- */
@media (min-width: 768px) {
  .masthead-sticky { padding: 48px; }
  .prose, .section-head { padding-left: 48px; padding-right: 48px; }
  .step { padding: 0 7vw; }
}
@media (max-width: 640px) {
  .masthead-title { padding: 1.75rem 1.5rem; }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .scroll-cue { animation: none; }
  .step-card { opacity: 1; transform: none; transition: none; }
  .masthead-title { opacity: 1 !important; transform: none !important; }
  .progress { display: none; }
}