/* ==========================================================================
   insight-article.css — /insights/<slug> article pages.
   --------------------------------------------------------------------------
   NET-NEW SECTION (no Oberon-template counterpart; see KNOWN-DIFFERENCES.md).
   The hero reuses the case-study `pd-her` header (css/pages/project-detail.css)
   with an .pd-her--art modifier below; the body is modeled structurally on a
   twistag.com/thinking article — sticky "on this page" TOC on the left,
   prose column on the right, meta strip, related-articles grid — restyled in
   the site idiom. Loads AFTER insights.css (the related grid reuses .ins__*).

   Prose is deliberately NOT run through data-split-text / data-reveal-inview:
   long-form text that fades in per word is hostile to reading and to
   crawlers rendering mid-animation. Only the hero animates.
   ========================================================================== */

/* Article titles run longer than case-study names ("Five signs a process is
   ready for AI" vs "Analytics dashboard"), and pd-her hangs its blurb
   absolutely below the title — 75px t-h1 over three lines collides with it.
   Cap the hero type a step down; the split/reveal mechanics are untouched. */
.pd-her--art .pd-her__title h1 { font-size: 56px; line-height: 100%; }
.pd-her--art .pd-her__title { max-width: 760px; }
@media (min-width: 810px) and (max-width: 1439.98px) {
  .pd-her--art .pd-her__title h1 { font-size: 46px; }
  .pd-her--art .pd-her__title { max-width: 620px; }
}
@media (max-width: 809.98px) {
  .pd-her--art .pd-her__title h1 { font-size: 34px; line-height: 104%; }
}

/* ---- meta strip: category / read time / updated ------------------------ */
.art-meta {
  /* relative + z-index: pd-her's dune marquee overflows the hero at phone
     and would paint over static siblings — same fix as .pd-project-info
     (position:relative) / .pg (z-index:1). Applies to .art/.art-rel too. */
  position: relative;
  z-index: 1;
  background: var(--c-white);
  border-bottom: 1px solid var(--c-stone);
  padding: 0 var(--page-pad-desktop);
}
.art-meta__inner {
  max-width: var(--page-max);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 56px;
  padding: 26px 0;
}
.art-meta__item { display: flex; flex-direction: column; gap: 2px; }
.art-meta__item .t-mono { color: var(--c-black); }
.art-meta__item--cat .t-mono { color: var(--c-orange); }

/* ---- body: TOC + prose ------------------------------------------------- */
.art {
  position: relative;
  z-index: 1;
  background: var(--c-white);
  padding: 90px var(--page-pad-desktop) 120px;
}
.art__inner {
  max-width: var(--page-max);
  margin: 0 auto;
  display: flex;
  align-items: flex-start;
  gap: 72px;
}
.art__toc {
  flex: 0 0 250px;
  position: sticky;
  top: 90px;
}
.art__toc-label { padding-bottom: 14px; }
.art__toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}
.art__toc-list a {
  display: block;
  text-decoration: none;
  padding: 7px 0 7px 16px;
  border-left: 1px solid var(--c-stone);
  transition: color .2s ease, border-color .2s ease;
}
.art__toc-list a:hover { color: var(--c-orange); }
.art__toc-list a.is-active { color: var(--c-orange); border-left-color: var(--c-orange); }

.art__body { flex: 1 1 0; min-width: 0; max-width: 720px; }

/* prose */
.art__body > p { margin: 0 0 22px; }
.art__body > p.t-body { color: var(--c-black); }
.art__body h2 {
  margin: 54px 0 18px;
  scroll-margin-top: 90px; /* fixed menu-line + air */
}
.art__body h2:first-of-type { margin-top: 0; }
.art__body a {
  color: inherit;
  text-decoration: underline;
  text-decoration-color: var(--c-orange);
  text-underline-offset: 3px;
  transition: color .2s ease;
}
.art__body a:hover { color: var(--c-orange); }
.art__body ul {
  margin: 0 0 22px;
  padding: 0 0 0 2px;
  list-style: none;
}
.art__body ul li {
  position: relative;
  padding: 0 0 10px 26px;
}
/* square bullet in the site's orange, mono-idiom */
.art__body ul li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: .5em;
  width: 7px;
  height: 7px;
  background: var(--c-orange);
}
.art__body strong { font-weight: 500; color: var(--c-black); }

.art__back { padding-top: 44px; }

/* ---- related articles --------------------------------------------------- */
.art-rel {
  position: relative;
  z-index: 1;
  background: var(--c-white);
  border-top: 1px solid var(--c-stone);
  padding: 72px var(--page-pad-desktop) 110px;
}
.art-rel__inner { max-width: var(--page-max); margin: 0 auto; }
.art-rel__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 24px;
  padding-bottom: 42px;
}

/* ---- breakpoints -------------------------------------------------------- */
@media (max-width: 1439.98px) {
  .art__inner { gap: 48px; }
  .art__toc { flex-basis: 220px; }
}
@media (max-width: 809.98px) {
  /* pd-her's phone blurb is position:absolute per spec (the reference keeps
     her at a fixed 629px regardless of description length), so it HANGS
     below the hero's flow box — worst case ~123px for a four-line blurb
     (42px pad + 4 x 20.25px lines). The case pages clear it with 142px of
     top padding on .pd-pi__logo-slot; articles clear it the same way with
     margin, so the dune band stays visible behind the hanging text. */
  .art-meta { margin-top: 145px; padding: 0 var(--page-pad-phone); }
  .art-meta__inner { gap: 10px 34px; padding: 22px 0; }
  .art { padding: 56px var(--page-pad-phone) 80px; }
  .art__inner { display: block; }
  .art__toc {
    position: static;
    padding-bottom: 44px;
  }
  .art-rel { padding: 56px var(--page-pad-phone) 80px; }
  .art-rel__head { flex-direction: column; gap: 12px; padding-bottom: 34px; }
}