/* =====================================================================
   BreakThrough Education — marketing site design system (v2, 2026-07-08)

   Identity: "the research folio". An established educational publisher's
   confidence — warm ivory paper, deep pine ink, measured gold — framing
   exuberant illustrated plates of children learning. Serif authority
   (Lora) carries the voice; the art carries the joy.
   ===================================================================== */

/* ---------- 1. Tokens ---------- */
:root {
  --ink:        #182720;   /* green-black text / dark grounds */
  --ink-soft:   #3d4f45;   /* secondary text */
  --ink-faint:  #6b7a71;   /* captions, fine print */
  --pine:       #1e4d38;   /* primary brand green (institutional) */
  --pine-deep:  #143427;
  --leaf:       #2e7d52;   /* interactive green */
  --leaf-soft:  #e3efe7;   /* tint for chips/marks */
  --gold:       #b98a2e;   /* plate numerals, rules, restrained accents */
  --gold-soft:  #f3ead6;
  --paper:      #f8f6f0;   /* page ground (warm ivory) */
  --paper-deep: #efeadd;   /* alternate sections (parchment) */
  --card:       #fffefa;
  --line:       rgba(24, 39, 32, .14);
  --line-soft:  rgba(24, 39, 32, .08);
  --serif: "Lora", Georgia, "Times New Roman", serif;
  --sans:  "Quicksand", "Segoe UI", system-ui, sans-serif;
  --shadow-card: 0 1px 2px rgba(24,39,32,.05), 0 12px 32px -18px rgba(24,39,32,.25);
  --shadow-plate: 0 2px 6px rgba(24,39,32,.10), 0 28px 60px -30px rgba(24,39,32,.45);
  --radius: 14px;
  --wrap: 1160px;
}

/* ---------- 2. Base ---------- */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--leaf); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
::selection { background: var(--gold-soft); }

h1, h2, h3, .serif { font-family: var(--serif); color: var(--ink); }
h1 { font-size: clamp(2.4rem, 5.2vw, 3.7rem); line-height: 1.12; font-weight: 600; letter-spacing: -.01em; text-wrap: balance; }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.4rem); line-height: 1.2; font-weight: 600; text-wrap: balance; }
h3 { font-size: 1.22rem; line-height: 1.35; font-weight: 600; }
.lead { font-size: 1.13rem; color: var(--ink-soft); max-width: 62ch; }
p  { color: var(--ink-soft); }
strong { color: var(--ink); }

.container { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }

/* small-caps label — the folio's running heads */
.eyebrow {
  display: inline-block;
  font-family: var(--sans);
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--pine);
  margin-bottom: 14px;
}
.eyebrow.gilt { color: var(--gold); }

/* section divider — hairline with the sprout fleuron, as in a set book */
.rule {
  display: flex; align-items: center; gap: 18px;
  max-width: var(--wrap); margin: 0 auto; padding: 0 24px;
}
.rule::before, .rule::after { content: ""; flex: 1; height: 1px; background: var(--line); }
.rule .fleuron { width: 22px; height: 22px; opacity: .85; }

/* ---------- 3. Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(248, 246, 240, .92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line-soft);
}
.site-header::before {   /* the gilt binding line */
  content: ""; display: block; height: 3px;
  background: linear-gradient(90deg, var(--pine), var(--gold) 50%, var(--pine));
}
.nav { display: flex; align-items: center; gap: 28px; height: 70px; }
.nav-logo { display: flex; align-items: center; gap: 10px; text-decoration: none !important; }
.nav-logo img { width: 34px; height: 34px; }
.nav-logo .wm { font-family: var(--serif); font-weight: 600; font-size: 1.18rem; color: var(--ink); letter-spacing: .01em; }
.nav-logo .wm .th { color: var(--pine); }
.nav-logo .wm .sub {
  display: block; font-family: var(--sans); font-weight: 700; font-size: .58rem;
  letter-spacing: .34em; text-transform: uppercase; color: var(--gold); margin-top: -2px;
}
.nav-links { display: flex; gap: 26px; margin-left: auto; }
.nav-links a {
  font-size: .84rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase;
  color: var(--ink-soft); padding: 6px 0; border-bottom: 2px solid transparent;
}
.nav-links a:hover { color: var(--pine); text-decoration: none; }
.nav-links a.active { color: var(--pine); border-bottom-color: var(--gold); }
.nav-actions { display: flex; align-items: center; gap: 16px; }
.nav-actions .login { font-size: .84rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-soft); }
.nav-toggle { display: none; background: none; border: 1px solid var(--line); border-radius: 8px; font-size: 1.2rem; color: var(--ink); width: 42px; height: 42px; cursor: pointer; }
.nav-mobile { display: none; }
.nav-mobile.open { display: flex; flex-direction: column; gap: 4px; padding: 10px 24px 22px; border-top: 1px solid var(--line-soft); background: var(--paper); }
.nav-mobile a { padding: 10px 2px; font-weight: 700; color: var(--ink); border-bottom: 1px solid var(--line-soft); }
.nav-mobile a:last-child { border-bottom: 0; }

/* ---------- 4. Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: var(--sans); font-weight: 700; text-decoration: none !important;
  border-radius: 999px; cursor: pointer; transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
  font-size: .95rem; padding: 12px 26px; line-height: 1.2;
}
.btn.primary { background: var(--pine); color: #fdfcf7; box-shadow: 0 10px 24px -12px rgba(30,77,56,.55); }
.btn.primary:hover { background: var(--pine-deep); transform: translateY(-1px); }
.btn.ghost { color: var(--pine); border: 1.5px solid var(--pine); background: transparent; }
.btn.ghost:hover { background: var(--leaf-soft); }
.btn.light { background: #fdfcf7; color: var(--pine); }
.btn.light:hover { transform: translateY(-1px); }
.btn.outline-light { border: 1.5px solid rgba(253,252,247,.7); color: #fdfcf7; }
.btn.outline-light:hover { background: rgba(253,252,247,.12); }
.btn.lg { padding: 15px 34px; font-size: 1.02rem; }
.btn.sm { padding: 9px 20px; font-size: .86rem; }
.mt-s { margin-top: 18px; }

/* ---------- 5. Sections ---------- */
.section { padding: 92px 0; }
.section.tight { padding: 44px 0; }
.section.alt { background: var(--paper-deep); }
.section.dark { background: linear-gradient(160deg, var(--ink) 0%, var(--pine-deep) 100%); }
.section.dark h2, .section.dark h3 { color: #f3f0e6; }
.section.dark p, .section.dark .lead { color: rgba(243,240,230,.78); }
.section.dark .eyebrow { color: var(--gold); }
.section-head { max-width: 720px; margin-bottom: 52px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head h2 + .lead { margin-top: 14px; }

/* ---------- 6. Hero ---------- */
.hero { padding: 84px 0 72px; }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 64px; align-items: center; }
.hero h1 { margin: 6px 0 20px; }
.hero .lead { margin-bottom: 30px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-note {
  display: flex; flex-wrap: wrap; gap: 8px 26px; margin-top: 26px;
  font-size: .8rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-faint);
}

/* ---------- 7. Plates (the artworks, framed as folio plates) ---------- */
.plate { margin: 0; }
.plate .plate-frame {
  background: var(--card);
  padding: 10px;
  border: 1px solid var(--line);
  outline: 1px solid var(--line-soft);
  outline-offset: 5px;
  border-radius: 4px;
  box-shadow: var(--shadow-plate);
}
.plate img { border-radius: 2px; width: 100%; height: auto; }
.plate figcaption {
  display: flex; align-items: baseline; gap: 14px;
  padding: 14px 6px 0;
}
.plate .plate-no {
  font-family: var(--serif); font-style: italic; font-weight: 500;
  color: var(--gold); font-size: .95rem; white-space: nowrap;
}
.plate .plate-cap { font-size: .88rem; color: var(--ink-faint); line-height: 1.5; }
.plate .plate-cap b { color: var(--ink-soft); font-weight: 700; }
.hero .plate { transform: rotate(.4deg); }

/* ---------- 8. Evidence strip (real numbers, set like a colophon) ---------- */
.evidence {
  display: grid; grid-template-columns: repeat(5, 1fr);
  border-top: 1px solid var(--line); border-bottom: 1px solid var(--line);
}
.evidence .ev {
  padding: 26px 18px; text-align: center;
  border-left: 1px solid var(--line-soft);
}
.evidence .ev:first-child { border-left: 0; }
.evidence .num {
  font-family: var(--serif); font-weight: 600; font-size: 1.9rem; color: var(--pine);
  font-variant-numeric: tabular-nums; line-height: 1.15;
}
.evidence .lab { font-size: .78rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--ink-faint); margin-top: 4px; }

/* ---------- 9. Method pillars ---------- */
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.pillar { background: var(--card); border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-card); display: flex; flex-direction: column; }
.pillar .pic { aspect-ratio: 16 / 9.4; overflow: hidden; }
.pillar .pic img { width: 100%; height: 100%; object-fit: cover; }
.pillar .body { padding: 26px 26px 30px; flex: 1; }
.pillar .roman { font-family: var(--serif); font-style: italic; color: var(--gold); font-size: .95rem; }
.pillar h3 { margin: 6px 0 10px; }
.pillar p { font-size: .98rem; }

/* ---------- 10. Curriculum table (set like a syllabus, no confetti) ---------- */
.syllabus { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: var(--card); }
.syl {
  padding: 30px 28px;
  border-right: 1px solid var(--line-soft); border-bottom: 1px solid var(--line-soft);
}
.syl:nth-child(3n) { border-right: 0; }
.syl:nth-child(n+4) { border-bottom: 0; }
.syl .af { font-family: var(--serif); font-weight: 600; font-size: 1.28rem; color: var(--pine); }
.syl .en { font-size: .78rem; font-weight: 700; letter-spacing: .13em; text-transform: uppercase; color: var(--gold); margin: 2px 0 10px; }
.syl p { font-size: .95rem; }

/* ---------- 11. Cards / grids (generic) ---------- */
.grid { display: grid; gap: 28px; }
.grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid.cols-4 { grid-template-columns: repeat(4, 1fr); }
.card {
  background: var(--card); border: 1px solid var(--line-soft); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow-card);
}
.card h3 { margin-bottom: 10px; }
.card p { font-size: .97rem; }
.card .k {
  font-size: .74rem; font-weight: 700; letter-spacing: .14em; text-transform: uppercase;
  color: var(--gold); display: block; margin-bottom: 10px;
}
.section.dark .card { background: rgba(253,252,247,.05); border-color: rgba(253,252,247,.14); box-shadow: none; }
.section.dark .card p { color: rgba(243,240,230,.75); }

/* ---------- 12. Tutor (dark) section ---------- */
.tutor-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 60px; align-items: center; }
.chat-mock {
  background: rgba(253,252,247,.055);
  border: 1px solid rgba(253,252,247,.16);
  border-radius: 18px; padding: 26px; max-width: 460px; margin-left: auto;
  box-shadow: 0 30px 70px -35px rgba(0,0,0,.6);
}
.chat-mock .who { display: flex; align-items: center; gap: 10px; margin-bottom: 18px; color: #f3f0e6; font-weight: 700; }
.chat-mock .who .dot { width: 34px; height: 34px; border-radius: 50%; background: var(--leaf-soft); display: grid; place-items: center; font-size: 1.1rem; }
.chat-mock .b { border-radius: 14px; padding: 12px 16px; margin: 10px 0; font-size: .95rem; line-height: 1.55; max-width: 92%; }
.chat-mock .b.child { background: rgba(253,252,247,.12); color: #f3f0e6; margin-left: auto; border-bottom-right-radius: 4px; }
.chat-mock .b.tutor { background: #f3f0e6; color: var(--ink); border-bottom-left-radius: 4px; }
.chat-mock .lang-tag { font-size: .68rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--gold); display: block; margin-top: 3px; }
.tut-points { list-style: none; margin-top: 26px; }
.tut-points li { display: flex; gap: 14px; padding: 12px 0; border-top: 1px solid rgba(253,252,247,.12); color: rgba(243,240,230,.85); font-size: .99rem; }
.tut-points li:first-child { border-top: 0; }
.tut-points .tick { color: var(--gold); font-family: var(--serif); font-weight: 600; }

/* ---------- 13. Charter (numbered commitments) ---------- */
.charter { counter-reset: charter; max-width: 840px; margin: 0 auto; }
.charter .item {
  counter-increment: charter;
  display: grid; grid-template-columns: 64px 1fr; gap: 22px;
  padding: 26px 0; border-top: 1px solid var(--line);
}
.charter .item:last-child { border-bottom: 1px solid var(--line); }
.charter .item::before {
  content: counter(charter, decimal-leading-zero);
  font-family: var(--serif); font-size: 1.7rem; font-weight: 500; font-style: italic;
  color: var(--gold); line-height: 1.1;
}
.charter h3 { margin-bottom: 6px; font-size: 1.1rem; }
.charter p { font-size: .97rem; }

/* ---------- 14. Steps / split / checks ---------- */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; counter-reset: step; }
.step { counter-increment: step; background: var(--card); border: 1px solid var(--line-soft); border-radius: var(--radius); padding: 30px 28px; box-shadow: var(--shadow-card); }
.step::before {
  content: counter(step, upper-roman);
  font-family: var(--serif); font-style: italic; color: var(--gold); font-size: 1.15rem; display: block; margin-bottom: 12px;
}
.step h3 { margin-bottom: 8px; }
.step p { font-size: .97rem; }
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }
.checks { list-style: none; margin: 18px 0 6px; }
.checks li { padding: 9px 0 9px 30px; position: relative; color: var(--ink-soft); font-size: .99rem; }
.checks li::before { content: "✓"; position: absolute; left: 2px; color: var(--leaf); font-weight: 700; }

/* ---------- 15. Quote ---------- */
.quote { max-width: 860px; text-align: center; position: relative; padding-top: 10px; }
.quote blockquote {
  font-family: var(--serif); font-size: clamp(1.35rem, 2.6vw, 1.8rem); font-weight: 500; font-style: italic;
  line-height: 1.5; color: var(--ink); margin: 10px 0 18px;
}
.quote blockquote::before { content: "“"; display: block; font-size: 4.6rem; line-height: .6; color: var(--gold); font-style: normal; margin-bottom: 18px; }
.quote .by { font-size: .82rem; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-faint); }

/* ---------- 16. CTA band ---------- */
.cta-band {
  background: linear-gradient(150deg, var(--pine) 0%, var(--pine-deep) 90%);
  border-radius: 22px; text-align: center; color: #fdfcf7;
  padding: 68px 44px; position: relative; overflow: hidden;
}
.cta-band::before {
  content: ""; position: absolute; inset: 10px; border: 1px solid rgba(253,252,247,.22); border-radius: 14px; pointer-events: none;
}
.cta-band h2 { color: #fdfcf7; margin-bottom: 12px; }
.cta-band p { color: rgba(253,252,247,.82); max-width: 56ch; margin: 0 auto 28px; }
.cta-band .hero-cta { justify-content: center; }

/* ---------- 17. Pricing ---------- */
.price-card { max-width: 520px; margin: 0 auto; text-align: center; border: 1px solid var(--line); position: relative; }
.price-card .price { font-family: var(--serif); font-size: 3rem; font-weight: 600; color: var(--pine); margin: 12px 0 2px; font-variant-numeric: tabular-nums; }
.price-card .price small { font-family: var(--sans); font-size: 1rem; font-weight: 600; color: var(--ink-faint); }
.faq { max-width: 780px; margin: 0 auto; }
.faq details { border-top: 1px solid var(--line); padding: 4px 0; }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { font-family: var(--serif); font-weight: 600; font-size: 1.08rem; padding: 18px 30px 18px 2px; cursor: pointer; list-style: none; position: relative; color: var(--ink); }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 6px; color: var(--gold); font-family: var(--serif); font-size: 1.4rem; line-height: 1; top: 16px; }
.faq details[open] summary::after { content: "–"; }
.faq details p { padding: 0 2px 20px; font-size: .98rem; }

/* ---------- 17b. Prose (legal / long-form) ---------- */
.prose { max-width: 760px; margin: 0 auto; }
.prose h1 { margin-bottom: 10px; }
.prose h2 { font-size: 1.35rem; margin: 40px 0 12px; }
.prose h3 { font-size: 1.08rem; margin: 26px 0 8px; }
.prose p { margin: 12px 0; font-size: .99rem; }
.prose ul { margin: 12px 0 12px 22px; }
.prose li { margin: 7px 0; color: var(--ink-soft); font-size: .99rem; }
.prose em { color: var(--ink-faint); }
.note { border: 1px solid var(--line); border-left: 3px solid var(--gold); background: var(--card); border-radius: 8px; padding: 14px 18px; font-size: .95rem; margin: 18px 0; }

/* ---------- 18. Footer ---------- */
.site-footer { background: var(--ink); color: rgba(243,240,230,.72); margin-top: 40px; }
.site-footer::before { content: ""; display: block; height: 3px; background: linear-gradient(90deg, var(--pine), var(--gold) 50%, var(--pine)); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 44px; padding: 60px 0 44px; }
.footer-brand .wm { font-family: var(--serif); font-weight: 600; font-size: 1.2rem; color: #f3f0e6; display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.footer-brand .wm img { width: 30px; height: 30px; }
.footer-brand .wm .th { color: #8fc7a8; }
.footer-brand p { font-size: .92rem; color: rgba(243,240,230,.6); max-width: 34ch; }
.footer-col h4 { font-size: .76rem; font-weight: 700; letter-spacing: .16em; text-transform: uppercase; color: var(--gold); margin-bottom: 16px; }
.footer-col a { display: block; color: rgba(243,240,230,.72); padding: 5px 0; font-size: .95rem; overflow-wrap: anywhere; }
.footer-col a:hover { color: #fff; }
.footer-bottom { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; border-top: 1px solid rgba(243,240,230,.14); padding: 22px 0 30px; font-size: .85rem; color: rgba(243,240,230,.5); }

/* ---------- 19. Reveal on scroll ----------
   Gated on html.js (set by an inline <script> in each page's head) so content is
   NEVER hidden when JavaScript is off; respects prefers-reduced-motion. */
.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .7s ease, transform .7s ease; }
.js .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .btn { transition: none; }
}

/* ---------- 20. Responsive ---------- */
@media (max-width: 1020px) {
  .hero-grid, .tutor-grid { grid-template-columns: 1fr; gap: 44px; }
  .chat-mock { margin: 0 auto; }
  .pillars, .steps, .grid.cols-3, .grid.cols-4 { grid-template-columns: 1fr 1fr; }
  .syllabus { grid-template-columns: 1fr 1fr; }
  .syl:nth-child(3n) { border-right: 1px solid var(--line-soft); }
  .syl:nth-child(2n) { border-right: 0; }
  .syl:nth-child(n+4) { border-bottom: 1px solid var(--line-soft); }
  .syl:nth-child(n+5) { border-bottom: 0; }
  .evidence { grid-template-columns: repeat(3, 1fr); }
  .evidence .ev:nth-child(4) { border-left: 0; }
  .evidence .ev:nth-child(n+4) { border-top: 1px solid var(--line-soft); }
}
@media (max-width: 720px) {
  .section { padding: 64px 0; }
  .hero { padding: 48px 0 56px; }
  .nav-links, .nav-actions { display: none; }
  .nav-toggle { display: block; margin-left: auto; }
  .pillars, .steps, .grid.cols-2, .grid.cols-3, .grid.cols-4, .split, .syllabus { grid-template-columns: 1fr; }
  .syl, .syl:nth-child(2n), .syl:nth-child(3n) { border-right: 0; }
  .syl:nth-child(n+2) { border-bottom: 0; border-top: 1px solid var(--line-soft); }
  .evidence { grid-template-columns: 1fr 1fr; }
  .evidence .ev { border-left: 0; border-top: 1px solid var(--line-soft); }
  .evidence .ev:nth-child(-n+2) { border-top: 0; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .charter .item { grid-template-columns: 44px 1fr; gap: 14px; }
  .cta-band { padding: 48px 24px; }
}