/* ==========================================================================
   The Economy Hub — page layouts
   Hub shelf, book cover page, chapter template, demo page, 404.
   ========================================================================== */

/* ---- hub ---- */

.hub-hero {
  padding-block: var(--space-8) var(--space-7);
  text-align: center;
}

.hub-hero__eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-brass-deep);
  margin: 0 0 var(--space-4);
}

.hub-hero h1 {
  font-size: var(--text-hero);
  font-weight: 640;
  margin: 0 auto;
}

.hub-hero__rule {
  width: 5rem;
  border-top: 2px solid var(--color-brass);
  margin: var(--space-5) auto;
}

.hub-hero__intro {
  max-width: 58ch;
  margin-inline: auto;
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink-soft);
}

.shelf {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(11.5rem, 1fr));
  gap: var(--space-6) var(--space-5);
  /* Covers share one width and aspect ratio, so top-aligning the items
     keeps every cover edge level regardless of caption length. */
  align-items: start;
  border-bottom: 4px double var(--color-rule-strong);
  padding-block: var(--space-5) var(--space-6);
}

.shelf__item {
  margin: 0;
}

.shelf__caption {
  padding-top: var(--space-4);
}

.shelf__status {
  margin-bottom: var(--space-2);
}

.shelf__desc {
  font-size: var(--text-caption);
  line-height: 1.5;
  color: var(--color-ink-soft);
  margin: var(--space-2) 0 0;
}

.shelf__open {
  display: inline-block;
  margin-top: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
}

.hub-note {
  max-width: 58ch;
  margin: var(--space-7) auto 0;
  text-align: center;
  font-size: var(--text-caption);
  color: var(--color-ink-soft);
}

/* ---- below the shelf: standalone surfaces ---- */

.hub-surface {
  max-width: 58ch;
  margin: var(--space-7) auto 0;
  text-align: center;
}

.hub-surface__eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-brass-deep);
  margin: 0 0 var(--space-3);
}

.hub-surface h2 {
  margin: 0 0 var(--space-3);
}

.hub-surface__desc {
  font-size: var(--text-caption);
  line-height: 1.6;
  color: var(--color-ink-soft);
  margin: 0 0 var(--space-3);
}

.hub-surface__open {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  margin: 0;
}

/* ---- book cover page ---- */

.book-hero {
  display: grid;
  gap: var(--space-7);
  padding-block: var(--space-7);
  align-items: start;
}

@media (min-width: 54rem) {
  .book-hero {
    grid-template-columns: minmax(16rem, 21rem) minmax(0, 1fr);
  }
}

.book-hero__cover {
  max-width: 21rem;
}

.book-hero__eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-brass-deep);
  margin: 0 0 var(--space-3);
}

.book-hero h1 {
  font-size: var(--text-h1);
  margin: 0 0 var(--space-3);
}

.book-hero__subtitle {
  font-style: italic;
  font-size: var(--text-lg);
  color: var(--color-ink-soft);
  margin: 0 0 var(--space-4);
}

.book-hero__status {
  margin-block: var(--space-4);
}

.book-hero__blurb {
  max-width: 58ch;
}

/* Contents list */

.book-toc {
  padding-block: var(--space-6) var(--space-7);
}

.book-toc__heading {
  font-size: var(--text-h2);
  border-bottom: var(--rule-emphatic);
  padding-bottom: var(--space-3);
  margin-bottom: var(--space-2);
}

.book-toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
  max-width: 46rem;
}

.book-toc li {
  display: flex;
  align-items: baseline;
  gap: var(--space-5);
  border-bottom: var(--rule-hairline);
  padding-block: var(--space-4);
}

.book-toc__num {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  font-weight: 600;
  color: var(--color-brass-deep);
  min-width: 2ch;
  text-align: right;
}

.book-toc__title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.25rem;
  line-height: 1.3;
}

.book-toc__title a {
  text-decoration: none;
}

.book-toc__title a:hover {
  text-decoration: underline;
  text-decoration-color: var(--color-brass);
}

.book-toc li:has(.book-toc__title:not(:has(a))) .book-toc__title {
  color: var(--color-ink);
}

.book-toc__state {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-soft);
  white-space: nowrap;
}

/* ---- chapter template ---- */

.chapter-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0 var(--space-7);
  padding-block: var(--space-6);
}

@media (min-width: 60rem) {
  .chapter-layout {
    grid-template-columns: var(--sidebar-width) minmax(0, var(--measure-prose));
    justify-content: center;
  }
}

.chapter-opener {
  grid-column: 1 / -1;
  border-bottom: var(--rule-hairline);
  margin-bottom: var(--space-6);
  padding-block: var(--space-6) var(--space-6);
  position: relative;
}

.chapter-opener__eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-brass-deep);
  margin: 0 0 var(--space-4);
}

/* The opener signature: an oversized numeral, letterpressed into the paper.
   Fill one shade below paper, hairline brass stroke, a thread of light
   under the top edge. Browsers without text-stroke get the tinted fill. */
.chapter-numeral {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(8rem, 22vw, 15rem);
  line-height: 0.85;
  color: var(--color-paper-shade);
  -webkit-text-stroke: 1.5px rgba(184, 137, 43, 0.55);
  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.75),
               0 -1px 0 rgba(32, 38, 42, 0.18);
  user-select: none;
}

.chapter-opener h1 {
  max-width: 24ch;
  margin-block: var(--space-4) 0;
}

.chapter-dek {
  max-width: 52ch;
  font-style: italic;
  font-size: var(--text-lg);
  line-height: 1.55;
  color: var(--color-ink-soft);
  margin: var(--space-4) 0 0;
}

/* Chapter TOC sidebar: <details> in the markup. toc.js populates the list,
   holds it open on desktop, and lets it collapse on mobile. */
.chapter-toc {
  margin-bottom: var(--space-6);
}

.chapter-toc summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-green);
  padding: var(--space-3) var(--space-4);
  border: var(--rule-hairline);
}

.chapter-toc summary::-webkit-details-marker {
  display: none;
}

.chapter-toc summary::before {
  content: "+";
  display: inline-block;
  width: 1.2em;
  color: var(--color-brass-deep);
}

.chapter-toc[open] summary::before {
  content: "\2212";
}

.chapter-toc__list {
  list-style: none;
  margin: 0;
  padding: var(--space-3) var(--space-4);
  border: var(--rule-hairline);
  border-top: 0;
}

.chapter-toc__list a {
  display: block;
  font-size: var(--text-caption);
  line-height: 1.4;
  text-decoration: none;
  color: var(--color-ink-soft);
  padding: var(--space-2) 0 var(--space-2) var(--space-3);
  border-left: 2px solid var(--color-rule);
}

.chapter-toc__list a:hover {
  color: var(--color-green);
  border-left-color: var(--color-brass);
}

.chapter-toc__list a[aria-current="location"] {
  color: var(--color-green);
  font-weight: 600;
  border-left-color: var(--color-brass);
}

@media (min-width: 60rem) {
  .chapter-toc {
    grid-column: 1;
    position: sticky;
    top: var(--space-5);
    align-self: start;
    margin-bottom: 0;
  }

  .chapter-toc summary {
    pointer-events: none;    /* held open by toc.js on desktop */
    border: 0;
    border-bottom: 2px solid var(--color-rule-strong);
    padding-inline: 0;
  }

  .chapter-toc summary::before {
    content: none;
  }

  .chapter-toc[open] summary::before {
    content: none;
  }

  .chapter-toc__list {
    border: 0;
    padding-inline: 0;
  }

  .chapter-body {
    grid-column: 2;
  }
}

.chapter-body {
  max-width: var(--measure-prose);
}

.chapter-body h2 {
  margin-block: var(--space-7) var(--space-4);
}

.chapter-body h2::before {
  content: "";
  display: block;
  width: 4rem;
  border-top: 2px solid var(--color-brass);
  margin-bottom: var(--space-3);
}

.chapter-body h3 {
  margin-block: var(--space-6) var(--space-3);
}

.chapter-pager {
  grid-column: 1 / -1;
}

@media (min-width: 60rem) {
  .chapter-pager {
    grid-column: 2;
  }
}

/* ---- kitchen-sink demo page ---- */

.demo-banner {
  margin-block: var(--space-6) 0;
  border: 1px solid var(--color-brass);
  background-color: var(--color-paper-deep);
  padding: var(--space-3) var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-brass-deep);
}

.demo-section {
  padding-block: var(--space-7) 0;
  max-width: var(--measure-prose);
}

.demo-section > h2 {
  border-bottom: var(--rule-emphatic);
  padding-bottom: var(--space-3);
}

.demo-section__note {
  font-size: var(--text-caption);
  color: var(--color-ink-soft);
}

.demo-swatches {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(9rem, 1fr));
  gap: var(--space-4);
  list-style: none;
  padding: 0;
}

.demo-swatch {
  border: var(--rule-hairline);
}

.demo-swatch__well {
  height: 3.5rem;
  border-bottom: var(--rule-hairline);
}

.demo-swatch__well[data-well="paper"] { background-color: var(--color-paper); }
.demo-swatch__well[data-well="paper-deep"] { background-color: var(--color-paper-deep); }
.demo-swatch__well[data-well="ink"] { background-color: var(--color-ink); }
.demo-swatch__well[data-well="ink-soft"] { background-color: var(--color-ink-soft); }
.demo-swatch__well[data-well="green"] { background-color: var(--color-green); }
.demo-swatch__well[data-well="brass"] { background-color: var(--color-brass); }
.demo-swatch__well[data-well="brass-deep"] { background-color: var(--color-brass-deep); }
.demo-swatch__well[data-well="oxide"] { background-color: var(--color-oxide); }
.demo-swatch__well[data-well="rule"] { background-color: var(--color-rule); }

.demo-swatch figcaption {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  padding: var(--space-2) var(--space-3);
}

/* ---- 404 ---- */

.error-page {
  text-align: center;
  padding-block: var(--space-8);
}

.error-page .chapter-numeral {
  font-size: clamp(9rem, 28vw, 17rem);
}

.error-page h1 {
  margin-block: var(--space-4);
}

.error-page p {
  max-width: 44ch;
  margin-inline: auto;
  color: var(--color-ink-soft);
}