/* =========================================================
   ARTICLES — Human AI Marketing
   Public, indexable long-form. Wears the v2 brand (teal /
   Fraunces / Inter) so it matches the home page that links
   here. The gated handbook keeps its own v1 stylesheet.
   ========================================================= */

:root {
  --paper: #EDE4D2;
  --bone:  #F7EFDD;
  --white: #FFFFFF;
  --ink:   #1B2738;
  --ink-90: rgba(27, 39, 56, 0.9);
  --ink-70: rgba(27, 39, 56, 0.72);
  --ink-50: rgba(27, 39, 56, 0.5);
  --ink-25: rgba(27, 39, 56, 0.25);
  --ink-15: rgba(27, 39, 56, 0.15);
  --ink-10: rgba(27, 39, 56, 0.1);
  --ink-05: rgba(27, 39, 56, 0.05);

  --teal: #4A7682;
  --teal-deep: #355864;
  --teal-soft: rgba(74, 118, 130, 0.1);
  --teal-edge: rgba(74, 118, 130, 0.35);
  --sumi: #0F1620;

  --serif: 'Fraunces', Georgia, serif;
  --sans:  'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --hand:  'Caveat', cursive;

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-soft: cubic-bezier(0.4, 0, 0.2, 1);

  --masthead-h: 62px;
}

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

html {
  font-size: 17px;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--masthead-h) + 24px);
  -webkit-text-size-adjust: 100%;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
}

body {
  margin: 0;
  background: var(--bone);
  color: var(--ink);
  font-family: var(--sans);
  font-weight: 400;
  line-height: 1.65;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
  /* the same faint paper tooth as the home page */
  background-image:
    radial-gradient(rgba(27, 39, 56, 0.022) 1px, transparent 1px),
    radial-gradient(rgba(27, 39, 56, 0.014) 1px, transparent 1px);
  background-size: 3px 3px, 7px 7px;
  background-position: 0 0, 1px 2px;
}

img { max-width: 100%; display: block; }

::selection { background: var(--teal); color: var(--bone); }

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--teal-edge);
  text-underline-offset: 3px;
  text-decoration-thickness: 1.5px;
  transition: text-decoration-color 0.2s var(--ease-soft);
}
a:hover { text-decoration-color: var(--teal); }

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip {
  position: absolute;
  top: -100px;
  left: 16px;
  background: var(--ink);
  color: var(--bone);
  padding: 10px 16px;
  border-radius: 4px;
  font-size: 0.875rem;
  text-decoration: none;
  z-index: 1000;
  transition: top 0.2s var(--ease-out);
}
.skip:focus { top: 12px; }

/* ===== Masthead ============================================ */

.masthead {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--masthead-h);
  background: rgba(247, 239, 221, 0.92);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--ink-10);
  z-index: 50;
}

.masthead__inner {
  height: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 28px;
  display: flex;
  align-items: center;
  gap: 22px;
}

.wordmark {
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
  font-family: var(--serif);
  font-weight: 400;
  font-size: 1.05rem;
  letter-spacing: 0.01em;
  color: var(--ink);
  white-space: nowrap;
  text-decoration: none;
}
.wordmark .ai { color: var(--teal); font-style: italic; }
.wordmark .dot { color: var(--ink-50); margin: 0 2px; }

.masthead__title {
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.95rem;
  color: var(--ink-70);
}

.masthead__stamp {
  margin-left: auto;
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-50);
  padding: 4px 11px;
  border: 1px solid var(--ink-15);
  border-radius: 999px;
  white-space: nowrap;
}

.progress {
  position: absolute;
  bottom: -1px; left: 0; right: 0;
  height: 2px;
  overflow: hidden;
}
.progress span {
  display: block;
  height: 100%;
  width: 0;
  background: var(--teal);
  transition: width 0.1s linear;
}

/* ===== Layout =============================================== */

.layout {
  max-width: 1200px;
  margin: 0 auto;
  padding: calc(var(--masthead-h) + 56px) 28px 96px;
  display: grid;
  grid-template-columns: 232px minmax(0, 1fr);
  gap: 76px;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
    gap: 44px;
    padding: calc(var(--masthead-h) + 32px) 24px 64px;
  }
}

/* ===== TOC ================================================== */

.toc {
  position: sticky;
  top: calc(var(--masthead-h) + 32px);
  align-self: start;
  font-size: 0.875rem;
  max-height: calc(100vh - var(--masthead-h) - 64px);
  overflow-y: auto;
  padding-right: 4px;
}

@media (max-width: 980px) {
  .toc {
    position: static;
    max-height: none;
    padding: 16px;
    background: var(--paper);
    border: 1px solid var(--ink-10);
    border-radius: 6px;
  }
}

.toc__label {
  margin: 0 0 12px;
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-50);
}

.toc ol { list-style: none; margin: 0; padding: 0; }
.toc li { border-top: 1px solid var(--ink-05); }
.toc li:first-child { border-top: none; }

.toc a {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 10px 0 10px 12px;
  text-decoration: none;
  color: var(--ink-70);
  border-left: 2px solid transparent;
  margin-left: -14px;
  transition: color 0.2s var(--ease-soft), border-color 0.2s var(--ease-soft), padding 0.2s var(--ease-soft);
}
.toc a:hover { color: var(--ink); }
.toc a.is-active {
  color: var(--ink);
  border-left-color: var(--teal);
  padding-left: 16px;
}

.toc__num {
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.85rem;
  color: var(--ink-50);
  min-width: 20px;
}
.toc a.is-active .toc__num {
  color: var(--teal);
  font-style: normal;
  font-weight: 600;
}

.toc__text { flex: 1; font-weight: 500; }

.toc__series-label {
  margin: 26px 0 10px;
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-50);
  padding-top: 16px;
  border-top: 1px solid var(--ink-10);
}

.toc__series { list-style: none; margin: 0; padding: 0; }
.toc__series li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 7px 0 7px 14px;
  color: var(--ink-50);
  font-size: 0.86rem;
}
.toc__series a { color: var(--ink-70); }
.toc__series-num {
  font-family: var(--serif);
  font-style: italic;
  color: var(--ink-25);
  min-width: 12px;
}

/* ===== Prose ================================================ */

.prose {
  max-width: 680px;
  font-size: 1.0625rem;
  line-height: 1.72;
}

.prose p, .prose ul, .prose ol { color: var(--ink-90); }
.prose strong { font-weight: 600; color: var(--ink); }
.prose em { font-style: italic; color: var(--ink); }

.prose ul, .prose ol { padding-left: 22px; }
.prose ul li, .prose ol li { margin: 8px 0; padding-left: 4px; }
.prose ul li::marker { color: var(--teal); }
.prose ol li::marker { color: var(--ink-50); }

.prose h3 {
  margin: 38px 0 12px;
  font-family: var(--sans);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.005em;
  color: var(--ink);
}

/* ===== Hero ================================================= */

.hero {
  margin-bottom: 56px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--ink-10);
}

.eyebrow {
  margin: 0 0 22px;
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--teal);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.eyebrow::before {
  content: '';
  width: 24px;
  height: 1px;
  background: var(--teal);
}

.hero h1 {
  margin: 0 0 24px;
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(2.3rem, 5vw, 3.5rem);
  line-height: 1.06;
  letter-spacing: -0.022em;
  font-variation-settings: "opsz" 100, "SOFT" 30;
  color: var(--ink);
}

.hero h1 em { font-style: italic; color: var(--teal); }

.lede {
  margin: 0;
  font-family: var(--serif);
  font-size: 1.24rem;
  font-weight: 400;
  line-height: 1.55;
  color: var(--ink-70);
  letter-spacing: -0.005em;
}

/* ===== Byline =============================================== */

.byline {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  margin: 26px 0 0;
  padding-top: 22px;
  border-top: 1px solid var(--ink-05);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-50);
}
.byline__author { color: var(--ink); font-weight: 500; }
.byline__sep { color: var(--ink-25); }

/* ===== Section ============================================== */

.section {
  margin-top: 72px;
  padding-top: 32px;
  border-top: 1px solid var(--ink-10);
  scroll-margin-top: calc(var(--masthead-h) + 24px);
}

.section:first-of-type {
  border-top: none;
  margin-top: 0;
  padding-top: 0;
}

.section__num {
  margin: 0 0 4px;
  font-family: var(--serif);
  font-style: italic;
  font-size: 1rem;
  color: var(--teal);
  letter-spacing: 0.04em;
}

.section h2 {
  margin: 0 0 26px;
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.6rem, 3vw, 2.15rem);
  line-height: 1.15;
  letter-spacing: -0.018em;
  color: var(--ink);
  font-variation-settings: "opsz" 60;
}

.section h2 em { font-style: italic; color: var(--teal); }

/* ===== Pull quote =========================================== */

.pull {
  margin: 44px 0;
  padding: 0 0 0 26px;
  border-left: 3px solid var(--teal);
}

.pull p {
  margin: 0;
  font-family: var(--serif);
  font-size: 1.42rem;
  font-weight: 400;
  line-height: 1.35;
  letter-spacing: -0.014em;
  color: var(--ink);
  font-variation-settings: "opsz" 60;
}

.pull cite {
  display: block;
  margin-top: 12px;
  font-family: var(--sans);
  font-style: normal;
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-50);
}

/* ===== Callouts ============================================= */

.callout {
  margin: 32px 0;
  padding: 22px 26px;
  border-left: 3px solid var(--ink-25);
  border-radius: 0 6px 6px 0;
  background: var(--paper);
}

.callout p { margin: 8px 0; }
.callout p:first-of-type { margin-top: 0; }
.callout p:last-child { margin-bottom: 0; }

.callout__label {
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--ink-50);
  display: block;
  margin-bottom: 8px;
}

.callout--teal {
  border-left-color: var(--teal);
  background: var(--teal-soft);
}
.callout--teal .callout__label { color: var(--teal-deep); }

/* ===== Figure shell ========================================
   Charts sit on a WHITE card, not on bone: the teal series
   clears 3:1 contrast against white. Every charted value is
   also printed as a direct label and repeated in a table, so
   no number is reachable by colour alone.
   ========================================================= */

.figure { margin: 44px 0; }

.figure__frame {
  position: relative;
  background: var(--white);
  border: 1px solid var(--ink-10);
  border-radius: 8px;
  padding: 26px 26px 20px;
  box-shadow: 0 1px 0 var(--ink-05), 0 18px 40px -28px rgba(27, 39, 56, 0.3);
}

.figure__label {
  margin: 0 0 5px;
  font-size: 0.66rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-50);
}

.figure__title {
  margin: 0 0 3px;
  font-family: var(--serif);
  font-weight: 400;
  font-size: 1.2rem;
  line-height: 1.25;
  letter-spacing: -0.012em;
  color: var(--ink);
  font-variation-settings: "opsz" 60;
}

.figure__sub {
  margin: 0 0 20px;
  font-size: 0.88rem;
  line-height: 1.5;
  color: var(--ink-70);
}

.figure figcaption {
  margin-top: 16px;
  padding-left: 14px;
  border-left: 2px solid var(--teal);
  font-size: 0.89rem;
  line-height: 1.55;
  color: var(--ink-70);
}
.figure figcaption strong { color: var(--ink); font-weight: 600; }

/* ===== Chart legend ========================================= */

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin: 0 0 16px;
  padding: 0;
  list-style: none;
  font-size: 0.82rem;
  color: var(--ink-70);
}

.legend li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
}

.legend__key {
  flex-shrink: 0;
  width: 18px;
  height: 2px;
  border-radius: 1px;
  background: var(--teal);
}

/* dashed = the hypothetical line, not a price anyone actually paid */
.legend__key--ref {
  background: none;
  height: 0;
  border-top: 2px dashed var(--ink-50);
}

/* ===== SVG chart internals ================================== */

.chart { display: block; width: 100%; height: auto; overflow: visible; }

/* gridlines: solid hairlines, one step off the surface */
.chart__grid { stroke: var(--ink-05); stroke-width: 1; }
.chart__axis { stroke: var(--ink-15); stroke-width: 1; }

.chart__tick {
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.04em;
  fill: var(--ink-50);
  font-variant-numeric: tabular-nums;
}

.chart__line {
  fill: none;
  stroke: var(--teal);
  stroke-width: 2;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.chart__ref {
  fill: none;
  stroke: var(--ink-50);
  stroke-width: 2;
  stroke-dasharray: 5 5;
  stroke-linecap: round;
}

/* the gap between what you pay and what inflation alone would justify */
.chart__wash { fill: var(--teal); opacity: 0.1; }

.chart__dot {
  fill: var(--teal);
  stroke: var(--white);   /* 2px surface ring */
  stroke-width: 2;
}
.chart__dot--ref { fill: var(--ink-50); }

.chart__value {
  font-family: var(--sans);
  font-size: 12.5px;
  font-weight: 600;
  fill: var(--ink);
}
.chart__value--muted { fill: var(--ink-50); font-weight: 500; font-size: 11.5px; }

/* event annotation — recessive: context, not a headline */
.chart__note {
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  fill: var(--ink-50);
}

.chart__rule { stroke: var(--ink-15); stroke-width: 1; }

.chart__hit { fill: transparent; cursor: crosshair; }

.chart__crosshair {
  stroke: var(--ink-25);
  stroke-width: 1;
  opacity: 0;
  pointer-events: none;
}

/* ===== Chart tooltip ======================================= */

.chart-tip {
  position: absolute;
  z-index: 5;
  pointer-events: none;
  opacity: 0;
  transform: translate(-50%, 0);
  background: var(--sumi);
  color: var(--bone);
  border-radius: 5px;
  padding: 9px 12px;
  font-size: 0.8rem;
  line-height: 1.45;
  white-space: nowrap;
  box-shadow: 0 8px 24px -10px rgba(15, 22, 32, 0.55);
  transition: opacity 0.14s var(--ease-soft);
}
.chart-tip.is-visible { opacity: 1; }

.chart-tip__year {
  display: block;
  margin-bottom: 4px;
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: rgba(247, 239, 221, 0.55);
}
.chart-tip__row { display: flex; align-items: center; gap: 7px; }
.chart-tip__swatch {
  width: 11px; height: 2px; border-radius: 1px; flex-shrink: 0;
  background: var(--teal);
}
.chart-tip__swatch--ref { background: rgba(247, 239, 221, 0.5); }
.chart-tip__val { font-weight: 600; font-variant-numeric: tabular-nums; }

/* ===== Peer bars ==========================================
   One series → one colour. The subject is highlighted; the
   peers recede. Colour follows the entity, never its rank.
   ========================================================= */

.bars { display: grid; gap: 10px; margin: 4px 0 0; padding: 0; list-style: none; }

.bars li {
  display: grid;
  grid-template-columns: minmax(100px, 140px) minmax(0, 1fr) 64px;
  align-items: center;
  gap: 14px;
  margin: 0;
  padding: 0;
}

.bars__name {
  font-size: 0.87rem;
  color: var(--ink-70);
  text-align: right;
  letter-spacing: -0.005em;
}

.bars li.is-subject .bars__name { font-weight: 600; color: var(--ink); }

.bars__track { height: 20px; display: flex; align-items: center; }

.bars__fill {
  height: 18px;                    /* ≤ 24px: never fills the slot */
  border-radius: 0 4px 4px 0;      /* square at baseline, 4px at the data-end */
  background: var(--ink-15);
}

.bars li.is-subject .bars__fill { background: var(--teal); }

.bars__val {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--ink-70);
  font-variant-numeric: tabular-nums;
}
.bars li.is-subject .bars__val { font-weight: 600; color: var(--ink); }

@media (max-width: 560px) {
  .bars li { grid-template-columns: minmax(78px, 104px) minmax(0, 1fr) 58px; gap: 10px; }
  .bars__name { font-size: 0.79rem; }
}

/* ===== Ledger table (the table view for every chart) ======== */

.ledger-wrap {
  margin: 34px 0;
  overflow-x: auto;
  border: 1px solid var(--ink-10);
  border-radius: 8px;
  background: var(--white);
}

.ledger {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  min-width: 520px;
}

.ledger caption {
  caption-side: top;
  text-align: left;
  padding: 18px 22px 14px;
  font-size: 0.66rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-50);
  border-bottom: 1px solid var(--ink-10);
}

.ledger th,
.ledger td {
  padding: 10px 22px;
  text-align: left;
  border-bottom: 1px solid var(--ink-05);
}

.ledger thead th {
  font-size: 0.64rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-50);
  font-weight: 500;
  white-space: nowrap;
}

.ledger tbody tr:last-child td { border-bottom: none; }
.ledger tbody tr:hover { background: var(--bone); }

.ledger td.num,
.ledger th.num {
  text-align: right;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.ledger tbody tr.is-now { background: var(--teal-soft); }
.ledger tbody tr.is-now:hover { background: var(--teal-soft); }
.ledger tbody tr.is-now td { font-weight: 600; color: var(--ink); }

.ledger .delta { color: var(--teal-deep); font-weight: 500; }
.ledger .flat { color: var(--ink-25); }

.ledger__est {
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-50);
  border: 1px solid var(--ink-15);
  border-radius: 999px;
  padding: 1px 6px;
  margin-left: 6px;
  vertical-align: 1px;
  white-space: nowrap;
}

/* ===== Stat row ============================================= */

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin: 38px 0;
  padding: 0;
  list-style: none;
  background: var(--ink-10);
  border: 1px solid var(--ink-10);
  border-radius: 8px;
  overflow: hidden;
}

.stats li { margin: 0; padding: 22px 20px; background: var(--paper); }

.stat__value {
  display: block;
  font-family: var(--sans);   /* never a serif on a figure */
  font-weight: 600;
  font-size: 1.9rem;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--teal-deep);
  margin-bottom: 7px;
  /* proportional figures: tabular-nums reads loose at this size */
}

.stat__label {
  display: block;
  font-size: 0.83rem;
  line-height: 1.45;
  color: var(--ink-70);
}

@media (max-width: 640px) {
  .stats { grid-template-columns: 1fr; }
}

/* ===== Method + sources ===================================== */

.method {
  margin: 30px 0 0;
  padding: 20px 24px;
  background: var(--paper);
  border: 1px solid var(--ink-10);
  border-radius: 6px;
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--ink-70);
}
.method strong { color: var(--ink); }

.sources { margin-top: 22px; font-size: 0.87rem; line-height: 1.6; }
.sources li { margin: 10px 0; color: var(--ink-70); }
.sources li::marker { color: var(--ink-25); }
.sources a { color: var(--ink-90); }

/* ===== Footer =============================================== */

.footer {
  margin-top: 88px;
  border-top: 1px solid var(--ink-10);
  background: var(--paper);
}

.footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 38px 28px;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer__brand {
  margin: 0;
  font-family: var(--serif);
  font-size: 0.95rem;
  color: var(--ink);
}
.footer__ai { color: var(--teal); font-style: italic; }

.footer__meta {
  margin: 0;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-50);
}

.footer a { color: var(--ink-70); }

.footer__id { display: grid; gap: 6px; justify-items: end; text-align: right; }

.footer__address {
  font-style: normal;
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--ink-50);
}

/* ===== Mobile refinements =================================== */

@media (max-width: 640px) {
  html { font-size: 16px; }
  .masthead__title { display: none; }
  .masthead__inner { padding: 0 20px; gap: 14px; }
  .layout { padding-left: 20px; padding-right: 20px; }
  .footer__inner { padding: 30px 20px; }
  .hero h1 { font-size: 2.05rem; }
  .lede { font-size: 1.1rem; }
  .figure__frame { padding: 20px 16px 16px; }
  .pull p { font-size: 1.2rem; }
}