/* ===== About page — companion to styles.css =====
   One signature element (the skill chain), everything else borrowed from the
   landing page's existing vocabulary (.section, .eyebrow, .feature-list, .btn). */

.about-hero {
  background: var(--navy-800);
  color: #fff;
  padding: 140px 0 84px;
  position: relative;
  overflow: hidden;
}
.about-hero-inner {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 64px;
  align-items: center;
}
.about-hero .eyebrow { color: var(--pink-500); }
.about-hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  line-height: 1.08;
  margin-bottom: 20px;
}
.about-hero h1 .glow { color: var(--pink-500); }
.about-hero p {
  color: rgba(255, 255, 255, 0.76);
  font-size: 1.05rem;
  line-height: 1.65;
  max-width: 52ch;
}
.about-hero p + p { margin-top: 16px; }

/* ---- Signature: the skill chain ----------------------------------------
   A real prerequisite chain with one link unlit. A child fails long division
   because regrouping never landed — the symptom and the cause sit three years
   apart, which is the whole thesis of the page. On scroll the dark link lights
   and everything downstream follows, in order. */
.chain {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}
.chain-step {
  display: grid;
  grid-template-columns: 26px 1fr;
  gap: 16px;
  align-items: start;
  padding-bottom: 26px;
  position: relative;
}
.chain-step:last-child { padding-bottom: 0; }
/* the wire between the dots */
.chain-step:not(:last-child)::before {
  content: '';
  position: absolute;
  left: 12px;
  top: 22px;
  bottom: 4px;
  width: 2px;
  background: rgba(255, 255, 255, 0.14);
  transition: background 0.5s ease;
}
.chain-dot {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.04);
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 700;
  color: transparent;
  transition: background 0.45s ease, border-color 0.45s ease, box-shadow 0.45s ease, color 0.45s ease;
}
.chain-skill {
  font-family: 'Chakra Petch', sans-serif;
  font-weight: 600;
  font-size: 15px;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.3;
  transition: color 0.45s ease;
}
.chain-grade {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.35);
  margin-top: 2px;
}
.chain-flag {
  display: inline-block;
  margin-top: 7px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  padding: 3px 9px;
  border-radius: 20px;
}
.chain-flag--gap { background: var(--pink-500); color: #fff; }
.chain-flag--symptom {
  background: transparent;
  color: rgba(255, 255, 255, 0.55);
  border: 1px dashed rgba(255, 255, 255, 0.3);
}

/* Mastered: already lit before the animation starts. */
.chain-step.is-lit .chain-dot {
  background: var(--pink-500);
  border-color: var(--pink-500);
  color: #fff;
}
.chain-step.is-lit .chain-skill { color: rgba(255, 255, 255, 0.9); }

/* The gap + everything it blocks. Lights on reveal, in order. */
.chain.is-visible .chain-step.is-gap .chain-dot {
  background: var(--pink-500);
  border-color: var(--pink-500);
  color: #fff;
  box-shadow: 0 0 0 6px rgba(244, 21, 126, 0.22);
}
.chain.is-visible .chain-step.is-gap .chain-skill { color: #fff; }
.chain.is-visible .chain-step.is-blocked .chain-dot {
  background: rgba(244, 21, 126, 0.85);
  border-color: rgba(244, 21, 126, 0.85);
  color: #fff;
}
.chain.is-visible .chain-step.is-blocked .chain-skill { color: rgba(255, 255, 255, 0.9); }
.chain.is-visible .chain-step:not(:last-child)::before { background: rgba(244, 21, 126, 0.5); }

/* Stagger: the cause lights first, then each thing it was holding up. */
.chain.is-visible .chain-step.is-gap .chain-dot { transition-delay: 0.15s; }
.chain.is-visible .chain-step.is-blocked:nth-of-type(3) .chain-dot,
.chain.is-visible .chain-step.is-blocked:nth-of-type(3) .chain-skill { transition-delay: 0.75s; }
.chain.is-visible .chain-step.is-blocked:nth-of-type(4) .chain-dot,
.chain.is-visible .chain-step.is-blocked:nth-of-type(4) .chain-skill { transition-delay: 1.05s; }
.chain.is-visible .chain-step.is-blocked:nth-of-type(5) .chain-dot,
.chain.is-visible .chain-step.is-blocked:nth-of-type(5) .chain-skill { transition-delay: 1.35s; }
.chain.is-visible .chain-step:not(:last-child)::before { transition-delay: 0.5s; }

.chain-caption {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 13.5px;
  color: rgba(255, 255, 255, 0.6);
  line-height: 1.6;
}
.chain-caption strong { color: #fff; font-weight: 600; }

/* ---- Prose sections ---- */
.about-statement {
  font-family: 'Chakra Petch', sans-serif;
  font-size: clamp(1.4rem, 2.8vw, 2rem);
  font-weight: 600;
  line-height: 1.35;
  color: var(--navy-800);
  max-width: 20ch;
}
.section-dark .about-statement { color: #fff; }
.about-cols {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 56px;
  align-items: start;
}
.about-prose p {
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}
.about-prose p + p { margin-top: 15px; }
.about-prose strong { color: var(--ink); font-weight: 600; }
.section-dark .about-prose p { color: rgba(255, 255, 255, 0.74); }
.section-dark .about-prose strong { color: #fff; }
.about-prose a { color: var(--pink-700); text-decoration: underline; text-underline-offset: 2px; }
.section-dark .about-prose a { color: var(--pink-500); }

/* ---- Closing CTA ---- */
.about-cta { text-align: center; padding: 84px 0; }
.about-cta h2 {
  font-size: clamp(1.8rem, 3.6vw, 2.6rem);
  color: var(--navy-800);
  margin-bottom: 14px;
}
.about-cta p {
  color: var(--ink-soft);
  max-width: 48ch;
  margin: 0 auto 28px;
  line-height: 1.65;
}

@media (max-width: 900px) {
  .about-hero-inner, .about-cols { grid-template-columns: 1fr; gap: 40px; }
  .about-hero { padding: 118px 0 60px; }
  .about-statement { max-width: none; }
}

/* The chain animates to explain a causal order; without motion it simply starts
   resolved rather than snapping through the sequence. */
@media (prefers-reduced-motion: reduce) {
  .chain-dot, .chain-skill, .chain-step::before { transition: none !important; }
}

/* Light hero variant — opt in with class="about-hero light". Drops the navy block
   for the white intro used across the site, and re-tunes the diagnostic chain
   (built white-on-dark) for a light background. Pink accents are unchanged. */
.about-hero.light { background: transparent; color: var(--ink, #14203a); padding: 34px 0 72px; }
.about-hero.light .breadcrumbs { margin: 0 0 26px; }
.about-hero.light h1 { color: var(--navy-900, #001830); }
.about-hero.light .chain-step:not(:last-child)::before { background: rgba(20, 32, 58, 0.14); }
.about-hero.light .chain-dot { border-color: rgba(20, 32, 58, 0.22); background: rgba(20, 32, 58, 0.03); }
.about-hero.light .chain-skill { color: rgba(20, 32, 58, 0.55); }
.about-hero.light .chain-grade { color: rgba(20, 32, 58, 0.42); }
.about-hero.light .chain-flag--symptom { color: rgba(20, 32, 58, 0.55); border-color: rgba(20, 32, 58, 0.28); }
.about-hero.light .chain-caption { color: rgba(20, 32, 58, 0.62); }
.about-hero.light .chain-step.is-lit .chain-skill { color: rgba(11, 31, 56, 0.92); }
.about-hero.light .chain.is-visible .chain-step.is-gap .chain-skill { color: var(--navy-900, #001830); }
.about-hero.light .chain.is-visible .chain-step.is-blocked .chain-skill { color: rgba(11, 31, 56, 0.9); }
/* Restore the "mastered" dot's pink fill on light (the base .chain-dot override
   above ties it on specificity and would otherwise win by source order). */
.about-hero.light .chain-step.is-lit .chain-dot { background: var(--pink-500, #f4157e); border-color: var(--pink-500, #f4157e); color: #fff; }