/* ============================================================
   DataStele — stone, ink, and vermillion seal
   ============================================================ */
:root {
  --stone:      #ece7dc;   /* aged stone / paper */
  --stone-deep: #ddd5c6;
  --ink:        #1c1a17;   /* carved ink */
  --ink-soft:   #4a463f;
  --muted:      #7a7266;
  --line:       #d3cbbb;
  --seal:       #a8322b;   /* vermillion seal / cinnabar */
  --seal-deep:  #8a2620;
  --gold:       #b0833a;   /* worn bronze */
  --paper:      #f4f1ea;
  --card:       #f7f4ed;
  --shadow:     0 1px 2px rgba(28,26,23,.06), 0 8px 30px rgba(28,26,23,.07);
  --maxw: 1120px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  font-family: "Inter", -apple-system, "Helvetica Neue", Arial, sans-serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }
a { color: inherit; text-decoration: none; }
em { font-style: italic; color: var(--seal-deep); }

h1, h2, h3, h4, h5 { line-height: 1.15; font-weight: 700; letter-spacing: -.015em; }
h2 { font-size: clamp(28px, 4vw, 42px); }
p  { font-size: 16px; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 600; font-size: 15px; border-radius: 8px;
  padding: 12px 22px; transition: transform .15s ease, box-shadow .2s ease, background .2s ease;
  cursor: pointer; border: 1px solid transparent; white-space: nowrap;
}
.btn-primary { background: var(--seal); color: #fff; box-shadow: var(--shadow); }
.btn-primary:hover { background: var(--seal-deep); transform: translateY(-1px); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--ink-soft); background: rgba(28,26,23,.03); }
.btn-sm { padding: 9px 16px; font-size: 14px; }
.btn-lg { padding: 15px 30px; font-size: 17px; }

/* ---------- nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(244,241,234,.82);
  backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease, box-shadow .2s ease;
}
.nav.scrolled { border-bottom-color: var(--line); box-shadow: 0 1px 12px rgba(28,26,23,.05); }
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 28px;
  height: 64px; display: flex; align-items: center; gap: 24px;
}
.brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 700; }
.brand-name { font-size: 19px; letter-spacing: -.02em; }
.brand-mark { flex: none; }
.nav-links { margin-left: auto; display: flex; gap: 26px; }
.nav-links a { font-size: 14.5px; color: var(--ink-soft); font-weight: 500; transition: color .15s; }
.nav-links a:hover { color: var(--seal); }
.nav .btn-primary { margin-left: 4px; }

/* ---------- hero ---------- */
.hero {
  position: relative; overflow: hidden;
  padding: clamp(70px, 11vw, 130px) 28px clamp(60px, 9vw, 110px);
  max-width: var(--maxw); margin: 0 auto;
  display: grid; grid-template-columns: 1.15fr .85fr; gap: 40px; align-items: center;
}
.hero-body { max-width: 620px; }
.eyebrow {
  color: var(--seal); font-weight: 600; font-size: 13.5px;
  letter-spacing: .12em; text-transform: uppercase; margin-bottom: 18px;
}
.hero h1 {
  font-size: clamp(37px, 5.6vw, 64px); line-height: 1.06; letter-spacing: -.03em;
  margin-bottom: 22px; text-wrap: balance;
}
.hero h1 .h1-lead { color: var(--ink-soft); font-weight: 600; }
.hero h1 .accent { color: var(--seal); }
.lede { font-size: clamp(17px, 2vw, 20px); color: var(--ink-soft); max-width: 560px; }
.hero-cta { display: flex; gap: 14px; margin: 32px 0 18px; flex-wrap: wrap; }
.hero-note { font-size: 14px; color: var(--muted); font-weight: 500; }

/* hero stele glyph */
.hero-glyph { display: flex; justify-content: center; align-items: center; }
.stele-tablet {
  position: relative;
  width: min(260px, 70%); aspect-ratio: 5 / 8;
  background: linear-gradient(160deg, var(--stone) 0%, var(--stone-deep) 100%);
  border-radius: 130px 130px 14px 14px;
  box-shadow: inset 0 2px 10px rgba(255,255,255,.5), inset 0 -8px 26px rgba(28,26,23,.12), var(--shadow);
  border: 1px solid var(--line);
  display: flex; align-items: center; justify-content: center;
}
.stele-tablet::before {
  content: ""; position: absolute; inset: 14px; border-radius: 118px 118px 8px 8px;
  border: 1.5px solid rgba(28,26,23,.14);
}
.stele-chars {
  font-family: "Noto Serif SC", serif; font-weight: 900;
  writing-mode: vertical-rl; text-orientation: upright;
  font-size: clamp(30px, 6vw, 46px); color: var(--ink);
  letter-spacing: .08em; line-height: 1.15;
  text-shadow: 0 1px 0 rgba(255,255,255,.4);
}
.stele-seal {
  position: absolute; bottom: 26px; right: 26px;
  font-family: "Noto Serif SC", serif; font-weight: 700;
  writing-mode: vertical-rl; text-orientation: upright;
  font-size: 15px; color: #fff; background: var(--seal);
  padding: 8px 5px; border-radius: 3px; letter-spacing: .1em;
  box-shadow: 0 2px 8px rgba(138,38,32,.4);
}

/* ---------- section scaffolding ---------- */
section { position: relative; }
.section-kicker {
  color: var(--seal); font-weight: 600; font-size: 13px;
  letter-spacing: .14em; text-transform: uppercase; margin-bottom: 14px;
}
.section-lede { font-size: 18px; color: var(--ink-soft); max-width: 680px; margin-top: 14px; }

/* ---------- story / 熹平石经 ---------- */
.story {
  background: linear-gradient(180deg, #211f1b 0%, #2a2823 100%);
  color: var(--stone); padding: clamp(70px, 9vw, 110px) 0;
}
.story .section-kicker { color: var(--gold); }
.story-title {
  font-family: "Noto Serif SC", serif; font-weight: 900;
  font-size: clamp(48px, 9vw, 92px); letter-spacing: .06em;
  color: var(--paper); line-height: 1;
}
.story-sub { font-family: "Noto Serif", serif; font-style: italic; font-size: 19px; color: #c9c0af; margin-top: 12px; }
.story-grid {
  display: grid; grid-template-columns: 1.1fr .9fr; gap: 54px;
  margin-top: 46px; align-items: start;
}
.story-narrative p { color: #d8cfbe; font-size: 16.5px; margin-bottom: 16px; }
.story-narrative b { color: var(--paper); }
.story-narrative em { color: #e8b96a; font-style: italic; }
.story-punch {
  font-family: "Noto Serif", serif; font-size: 20px !important;
  color: var(--paper) !important; font-style: italic;
  border-left: 3px solid var(--seal); padding-left: 18px; margin-top: 26px !important;
}
.story-map {
  background: rgba(244,241,234,.05); border: 1px solid rgba(244,241,234,.14);
  border-radius: 14px; padding: 26px;
}
.story-map h3 { color: var(--gold); font-size: 17px; margin-bottom: 16px; }
.thennow { width: 100%; border-collapse: collapse; }
.thennow th {
  text-align: left; font-size: 12px; text-transform: uppercase; letter-spacing: .1em;
  color: #b7ae9d; padding: 8px 10px 8px 0; border-bottom: 1px solid rgba(244,241,234,.16);
}
.thennow th:last-child { color: var(--seal); }
.thennow td {
  font-size: 14px; padding: 12px 14px 12px 0; vertical-align: top;
  border-bottom: 1px solid rgba(244,241,234,.08); color: #cfc6b5; width: 50%;
}
.thennow td:last-child { color: var(--paper); font-weight: 500; }

/* ---------- problem ---------- */
.problem { padding: clamp(70px, 9vw, 110px) 0; }
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin: 44px 0 40px; }
.stat {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 28px 24px; box-shadow: var(--shadow);
}
.stat-num { font-size: 34px; font-weight: 700; color: var(--seal); letter-spacing: -.02em; margin-bottom: 10px; }
.stat-num .arrow { color: var(--muted); font-weight: 400; }
.stat p { font-size: 14.5px; color: var(--ink-soft); }
.pull {
  font-family: "Noto Serif", serif; font-size: clamp(20px, 3vw, 27px); font-style: italic;
  color: var(--ink); max-width: 820px; margin: 8px auto 0; text-align: center; line-height: 1.4;
}
.pull cite { display: block; font-size: 15px; font-style: normal; color: var(--muted); margin-top: 14px; }

/* ---------- product ---------- */
.product { padding: clamp(70px, 9vw, 110px) 0; background: var(--stone); }
.two-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 26px; margin-top: 46px; }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 16px;
  padding: 34px; box-shadow: var(--shadow); position: relative;
}
.card-num {
  font-family: "Noto Serif", serif; font-size: 15px; font-weight: 600; color: var(--seal);
  letter-spacing: .1em; margin-bottom: 14px;
}
.card h3 { font-size: 24px; margin-bottom: 14px; }
.card > p { color: var(--ink-soft); font-size: 15.5px; margin-bottom: 16px; }
.ticked { list-style: none; display: flex; flex-direction: column; gap: 10px; margin: 4px 0 16px; }
.ticked li { position: relative; padding-left: 26px; font-size: 15px; color: var(--ink-soft); }
.ticked li b { color: var(--ink); }
.ticked li::before {
  content: "刻"; position: absolute; left: 0; top: 1px;
  font-family: "Noto Serif SC", serif; font-size: 13px; color: var(--seal);
  background: rgba(168,50,43,.1); width: 18px; height: 18px; border-radius: 4px;
  display: flex; align-items: center; justify-content: center;
}
.card-foot { font-size: 13.5px !important; color: var(--muted) !important; border-top: 1px solid var(--line); padding-top: 14px; margin-top: 4px !important; }
code {
  font-family: "SF Mono", "Menlo", monospace; font-size: .86em;
  background: rgba(28,26,23,.06); padding: 2px 6px; border-radius: 4px; color: var(--seal-deep);
}

/* ---------- how ---------- */
.how { padding: clamp(70px, 9vw, 110px) 0; }
.flow { display: flex; align-items: stretch; gap: 12px; margin: 46px 0 56px; flex-wrap: wrap; }
.flow-step {
  flex: 1 1 200px; background: var(--card); border: 1px solid var(--line);
  border-radius: 14px; padding: 24px; box-shadow: var(--shadow);
}
.flow-badge {
  width: 34px; height: 34px; border-radius: 9px; background: var(--seal); color: #fff;
  display: flex; align-items: center; justify-content: center; font-weight: 700; margin-bottom: 14px;
}
.flow-step h4 { font-size: 18px; margin-bottom: 8px; }
.flow-step p { font-size: 14px; color: var(--ink-soft); }
.flow-arrow { display: flex; align-items: center; color: var(--muted); font-size: 22px; font-weight: 300; }
.features { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px 40px; }
.feature { border-top: 2px solid var(--seal); padding-top: 16px; }
.feature h4 { font-size: 18px; margin-bottom: 8px; }
.feature p { font-size: 15px; color: var(--ink-soft); }

/* ---------- shift ---------- */
.shift { padding: clamp(70px, 9vw, 110px) 0; background: var(--stone); text-align: center; }
.shift h2 { margin-bottom: 22px; }
.shift-lede { font-size: 19px; color: var(--ink-soft); max-width: 760px; margin: 0 auto 20px; }
.shift-lede b { color: var(--ink); }
.shift-close {
  font-family: "Noto Serif", serif; font-style: italic; font-size: 21px;
  color: var(--ink); max-width: 720px; margin: 0 auto;
}

/* ---------- cta ---------- */
.cta {
  padding: clamp(80px, 10vw, 120px) 0; text-align: center;
  background: linear-gradient(180deg, #211f1b 0%, #2a2823 100%); color: var(--paper);
  position: relative; overflow: hidden;
}
.cta-seal {
  font-family: "Noto Serif SC", serif; font-weight: 900; font-size: 130px;
  color: var(--seal); opacity: .16; line-height: 1; margin-bottom: -20px;
  border: 6px solid var(--seal); border-radius: 12px; width: 150px; height: 150px;
  display: inline-flex; align-items: center; justify-content: center; margin-bottom: 24px;
}
.cta h2 { color: var(--paper); margin-bottom: 14px; }
.cta p { color: #c9c0af; font-size: 18px; margin-bottom: 30px; }

/* ---------- footer ---------- */
.footer { background: #16130f; color: #b7ae9d; padding: 60px 0 30px; }
.footer-inner { display: grid; grid-template-columns: 1.2fr 2fr; gap: 40px; padding-bottom: 40px; border-bottom: 1px solid rgba(244,241,234,.1); }
.footer .brand-name { color: var(--paper); }
.footer-pron { font-size: 14px; margin-top: 16px; max-width: 320px; }
.footer-pron b { color: var(--stone); }
.footer-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.footer-cols h5 { color: var(--stone); font-size: 13px; text-transform: uppercase; letter-spacing: .1em; margin-bottom: 14px; }
.footer-cols a { display: block; font-size: 14.5px; color: #a49b8a; margin-bottom: 9px; transition: color .15s; }
.footer-cols a:hover { color: var(--seal); }
.footer-legal { display: flex; justify-content: space-between; padding-top: 24px; font-size: 13px; color: #6e675b; flex-wrap: wrap; gap: 8px; }

/* ---------- reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; text-align: left; }
  .hero-glyph { order: -1; margin-bottom: 10px; }
  .stele-tablet { width: 190px; }
  .story-grid { grid-template-columns: 1fr; gap: 34px; }
  .stats { grid-template-columns: 1fr; }
  .two-cards { grid-template-columns: 1fr; }
  .features { grid-template-columns: 1fr; }
  .flow-arrow { display: none; }
  .nav-links { display: none; }
  .footer-inner { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}