/* ===========================================================
   TALL — scholarly editorial design system
   Palette, typography, components shared across all pages
   =========================================================== */

:root {
  /* Greens — preserve TALL signature */
  --tall: #4DB280;
  --tall-dark: #2f8a5b;
  --tall-deep: #0f3d2a;
  --tall-soft: #e4f7ec;
  --tall-tint: #f0faf4;

  /* Editorial neutrals */
  --ink: #0f1a14;
  --ink-soft: #2d3a32;
  --ink-muted: #5e6a63;
  --rule: #d9d2c2;
  --rule-soft: #eae2d0;

  /* Paper backgrounds */
  --paper: #faf7ef;
  --paper-warm: #f4efe1;
  --paper-deep: #eae3d0;
  --surface: #ffffff;

  /* Accents */
  --amber: #b6551e;
  --amber-soft: #f7ebda;
  --plum: #5a2a55;

  /* Type scale */
  --font-display: "Fraunces", "Cormorant Garamond", Georgia, serif;
  --font-body: "Instrument Sans", "Figtree", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, monospace;

  /* Motion */
  --ease: cubic-bezier(.22,.61,.36,1);
}

/* ===========================================================
   RESET + BASE
   =========================================================== */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  font-feature-settings: "ss01", "ss02", "cv11";
  overflow-x: hidden;
}

/* Paper grain overlay (subtle, global) */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: .35;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='220' height='220'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0.05  0 0 0 0 0.1  0 0 0 0 0.08  0 0 0 0.06 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)'/></svg>");
}

main, section, nav, footer, header { position: relative; z-index: 2; }

img { max-width: 100%; height: auto; display: block; }

a { color: var(--tall-dark); text-decoration: none; transition: color .2s var(--ease); }
a:hover { color: var(--tall-deep); }

/* ===========================================================
   TYPOGRAPHY
   =========================================================== */
.display, h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--ink);
  margin: 0;
  letter-spacing: -0.015em;
}

h1 { font-weight: 400; font-variation-settings: "opsz" 144, "SOFT" 30; line-height: 1.02; }
h2 { font-weight: 500; font-variation-settings: "opsz" 96, "SOFT" 40; line-height: 1.08; }
h3 { font-weight: 600; font-variation-settings: "opsz" 48, "SOFT" 50; line-height: 1.2; }
h4 { font-weight: 600; font-variation-settings: "opsz" 14, "SOFT" 50; line-height: 1.3; }

.display-xl {
  font-size: clamp(3rem, 6.5vw, 6.5rem);
  font-weight: 400;
  font-style: normal;
  line-height: .95;
  letter-spacing: -0.035em;
}

.display-lg { font-size: clamp(2.5rem, 5vw, 4.25rem); line-height: 1.05; letter-spacing: -0.03em; }
.display-md { font-size: clamp(2rem, 3.5vw, 3rem); line-height: 1.1; letter-spacing: -0.02em; }
.display-sm { font-size: clamp(1.5rem, 2.2vw, 2rem); line-height: 1.2; }

.italic-display {
  font-style: italic;
  font-variation-settings: "opsz" 144, "SOFT" 100;
}

/* Editorial kicker — a small-caps label above headings */
.kicker {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--font-body);
  font-size: .7rem;
  font-weight: 600;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--tall-dark);
}
.kicker::before {
  content: "";
  width: 28px;
  height: 1px;
  background: var(--tall-dark);
}

.eyebrow {
  display: block;
  font-family: var(--font-body);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: .5rem;
}

.lede {
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 1.6vw, 1.45rem);
  font-weight: 350;
  font-variation-settings: "opsz" 30, "SOFT" 50;
  line-height: 1.45;
  color: var(--ink-soft);
  letter-spacing: -0.005em;
}

p { margin: 0 0 1rem; color: var(--ink-soft); }
p.muted { color: var(--ink-muted); }
.small { font-size: .92rem; color: var(--ink-muted); }

/* Drop cap for editorial paragraphs */
.drop-cap::first-letter {
  font-family: var(--font-display);
  font-size: 4.5em;
  float: left;
  line-height: .85;
  padding: .18em .12em 0 0;
  color: var(--tall-deep);
  font-weight: 500;
  font-variation-settings: "opsz" 144, "SOFT" 30;
}

/* ===========================================================
   LAYOUT UTILITIES
   =========================================================== */
.container { max-width: 1240px; margin: 0 auto; padding: 0 clamp(1.25rem, 3vw, 2.25rem); }
.container-narrow { max-width: 860px; margin: 0 auto; padding: 0 clamp(1.25rem, 3vw, 2.25rem); }
.container-wide { max-width: 1480px; margin: 0 auto; padding: 0 clamp(1.25rem, 3vw, 2.25rem); }

.grid { display: grid; gap: clamp(1.5rem, 3vw, 2.5rem); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }

@media (max-width: 960px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .grid-12 { grid-template-columns: 1fr; }
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: .5rem; } .gap-3 { gap: .75rem; } .gap-4 { gap: 1rem; }
.gap-6 { gap: 1.5rem; } .gap-8 { gap: 2rem; }

.text-center { text-align: center; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0; } .mt-2 { margin-top: .5rem; } .mt-4 { margin-top: 1rem; }
.mt-6 { margin-top: 1.5rem; } .mt-8 { margin-top: 2rem; } .mt-12 { margin-top: 3rem; }
.mb-0 { margin-bottom: 0; } .mb-2 { margin-bottom: .5rem; } .mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; } .mb-8 { margin-bottom: 2rem; } .mb-12 { margin-bottom: 3rem; }

/* Section spacing */
section { padding: clamp(4rem, 8vw, 7rem) 0; position: relative; }
.section-tight { padding: clamp(2.5rem, 5vw, 4rem) 0; }

/* ===========================================================
   NAVBAR — fixed, paper transparent -> solid on scroll
   =========================================================== */
.site-nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  background: rgba(250, 247, 239, 0.72);
  backdrop-filter: saturate(140%) blur(14px);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: background .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease);
}
.site-nav.scrolled {
  background: rgba(250, 247, 239, 0.94);
  border-bottom-color: var(--rule);
  box-shadow: 0 8px 40px -30px rgba(15, 61, 42, 0.35);
}
.nav-inner {
  max-width: 1480px;
  margin: 0 auto;
  padding: .9rem clamp(1.25rem, 3vw, 2.25rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}
.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: .75rem;
  color: var(--ink);
}
.nav-brand img { height: 36px; width: auto; }
.nav-brand .wordmark {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  color: var(--tall-deep);
}
.nav-brand .wordmark sup {
  font-size: .55rem;
  font-family: var(--font-body);
  font-weight: 700;
  letter-spacing: .15em;
  color: var(--tall-dark);
  background: var(--tall-soft);
  padding: .18rem .4rem;
  border-radius: 999px;
  margin-left: .4rem;
  vertical-align: middle;
}
.nav-links { display: flex; align-items: center; gap: 2rem; }
.nav-links a {
  color: var(--ink-soft);
  font-size: .95rem;
  font-weight: 500;
  position: relative;
  padding: .3rem 0;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%;
  bottom: -2px;
  height: 1px;
  background: var(--tall-dark);
  transition: right .3s var(--ease);
}
.nav-links a:hover { color: var(--tall-deep); }
.nav-links a:hover::after { right: 0; }
.nav-links a.active { color: var(--tall-deep); }
.nav-links a.active::after { right: 0; }

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  font-size: .9rem;
  font-weight: 600;
  padding: .55rem 1.1rem;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  transition: background .2s var(--ease), transform .2s var(--ease);
}
.nav-cta:hover { background: var(--tall-deep); color: var(--paper); transform: translateY(-1px); }

.nav-burger {
  display: none;
  width: 42px; height: 42px;
  background: transparent;
  border: 1px solid var(--rule);
  border-radius: 999px;
  color: var(--ink);
  cursor: pointer;
}

.mobile-menu {
  display: none;
  border-top: 1px solid var(--rule);
  background: var(--paper);
}
.mobile-menu a {
  display: block;
  padding: .9rem clamp(1.25rem, 3vw, 2.25rem);
  color: var(--ink);
  border-bottom: 1px solid var(--rule-soft);
  font-weight: 500;
}

@media (max-width: 900px) {
  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-burger { display: inline-flex; align-items: center; justify-content: center; }
}

/* Progress accent line (replaces old gradient bar) */
.nav-rule {
  height: 2px;
  background: linear-gradient(90deg, var(--tall-deep) 0%, var(--tall) 40%, transparent 100%);
  opacity: .9;
}

/* ===========================================================
   BUTTONS
   =========================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  padding: .85rem 1.5rem;
  font-family: var(--font-body);
  font-size: .95rem;
  font-weight: 600;
  letter-spacing: .01em;
  border-radius: 999px;
  transition: all .25s var(--ease);
  border: 1px solid transparent;
  cursor: pointer;
  white-space: nowrap;
}
.btn-primary {
  background: var(--ink);
  color: var(--paper);
}
.btn-primary:hover {
  background: var(--tall-deep);
  color: var(--paper);
  transform: translateY(-1px);
  box-shadow: 0 10px 30px -15px rgba(15, 61, 42, 0.6);
}
.btn-ghost {
  background: transparent;
  border-color: var(--ink);
  color: var(--ink);
}
.btn-ghost:hover {
  background: var(--ink);
  color: var(--paper);
}
.btn-leaf {
  background: var(--tall-deep);
  color: var(--paper);
}
.btn-leaf:hover {
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-1px);
}
.btn svg { width: 18px; height: 18px; }

/* ===========================================================
   CARDS + SURFACES
   =========================================================== */
.card {
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 1.75rem;
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 20px 60px -30px rgba(15, 61, 42, 0.25);
  border-color: var(--tall);
}

.card-paper {
  background: var(--paper-warm);
  border: 1px solid var(--rule);
  padding: 2rem;
  border-radius: 4px;
  position: relative;
}
.card-paper::before {
  content: "";
  position: absolute;
  top: -6px; right: -6px; bottom: -6px; left: -6px;
  background: var(--paper-deep);
  z-index: -1;
  border-radius: 4px;
  transform: rotate(-.4deg);
  opacity: .35;
}

.card-outline {
  background: transparent;
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 1.5rem;
}

/* Fine horizontal rule */
.rule {
  height: 1px;
  background: var(--rule);
  border: 0;
  margin: 0;
}
.rule-heavy { background: var(--ink); height: 1px; }

/* ===========================================================
   BADGES
   =========================================================== */
.badge {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .3rem .7rem;
  font-family: var(--font-body);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .15em;
  text-transform: uppercase;
  border-radius: 999px;
}
.badge-new { background: var(--tall-deep); color: var(--paper); }
.badge-updated { background: var(--amber); color: #fff; }
.badge-soft { background: var(--tall-soft); color: var(--tall-deep); }
.badge-ink { background: var(--ink); color: var(--paper); }
.badge-outline { border: 1px solid var(--rule); background: transparent; color: var(--ink-muted); }

/* ===========================================================
   STATS + DATA ELEMENTS
   =========================================================== */
.stat {
  padding: 1.75rem 0;
  border-top: 1px solid var(--rule);
  position: relative;
}
.stat-num {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(2.4rem, 4vw, 3.8rem);
  line-height: 1;
  letter-spacing: -0.035em;
  color: var(--tall-deep);
  font-variation-settings: "opsz" 144, "SOFT" 40;
}
.stat-label {
  font-family: var(--font-body);
  font-size: .82rem;
  font-weight: 600;
  color: var(--ink-muted);
  letter-spacing: .14em;
  text-transform: uppercase;
  margin-top: .5rem;
}
.stat-sub {
  font-size: .9rem;
  color: var(--ink-muted);
  margin-top: .4rem;
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 14;
}

/* ===========================================================
   FIGURES
   =========================================================== */
.figure {
  margin: 0;
}
.figure img {
  border-radius: 8px;
  border: 1px solid var(--rule);
  background: var(--surface);
  box-shadow: 0 40px 80px -60px rgba(15, 26, 20, 0.35);
}
.figcaption {
  margin-top: 1rem;
  font-size: .88rem;
  color: var(--ink-muted);
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 14;
  line-height: 1.5;
}
.figcaption strong {
  font-family: var(--font-body);
  font-style: normal;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  font-size: .74rem;
  color: var(--tall-deep);
  margin-right: .5rem;
}

/* ===========================================================
   CODE BLOCKS
   =========================================================== */
.code-block {
  background: #0f1a14;
  color: #dde6d8;
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  font-family: var(--font-mono);
  font-size: .88rem;
  line-height: 1.7;
  position: relative;
  overflow-x: auto;
  border: 1px solid #1e2e24;
}
.code-block code { font-family: inherit; color: inherit; white-space: pre; }
.code-block .copy-btn {
  position: absolute;
  top: .5rem; right: .5rem;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.12);
  color: #9fb4a4;
  padding: .3rem .7rem;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all .2s var(--ease);
}
.code-block .copy-btn:hover { background: rgba(255,255,255,.12); color: #fff; }
.code-block .prompt { color: #4DB280; user-select: none; }
.code-block .comment { color: #6f8378; font-style: italic; }

/* ===========================================================
   CITATION BLOCK
   =========================================================== */
.citation {
  background: var(--paper-warm);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--tall-deep);
  padding: 1.75rem 2rem;
  border-radius: 2px;
  font-family: var(--font-body);
  position: relative;
}
.citation .cite-label {
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--tall-deep);
  margin-bottom: .8rem;
}
.citation .cite-authors { font-weight: 600; color: var(--ink); }
.citation .cite-title {
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 14;
  font-weight: 450;
  color: var(--ink);
  display: block;
  margin: .3rem 0;
  line-height: 1.4;
}
.citation .cite-venue { color: var(--ink-muted); }
.citation .cite-actions {
  display: flex;
  gap: .6rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}
.cite-btn {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .45rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--rule);
  background: var(--surface);
  font-size: .82rem;
  font-weight: 600;
  color: var(--ink-soft);
  font-family: var(--font-body);
}
.cite-btn:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }

/* ===========================================================
   TAG / PILL LIST
   =========================================================== */
.pill {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .35rem .75rem;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 999px;
  font-size: .8rem;
  font-weight: 500;
  color: var(--ink-soft);
  font-family: var(--font-mono);
}

/* ===========================================================
   FOOTER
   =========================================================== */
.site-footer {
  background: var(--ink);
  color: var(--paper);
  padding: 4rem 0 2rem;
  position: relative;
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at top left, rgba(77,178,128,.18), transparent 55%),
              radial-gradient(ellipse at bottom right, rgba(77,178,128,.08), transparent 60%);
  pointer-events: none;
}
.site-footer .container { position: relative; }
.site-footer a { color: rgba(250,247,239,.7); }
.site-footer a:hover { color: var(--tall); }
.site-footer h4 {
  font-family: var(--font-body);
  text-transform: uppercase;
  letter-spacing: .18em;
  font-size: .75rem;
  color: rgba(250,247,239,.5);
  margin-bottom: 1rem;
  font-weight: 600;
}
.footer-brand .footer-title {
  font-family: var(--font-display);
  font-size: 2.2rem;
  font-weight: 400;
  color: var(--paper);
  line-height: 1;
  letter-spacing: -.02em;
}
.footer-brand .footer-sub {
  display: block;
  font-size: .85rem;
  color: rgba(250,247,239,.6);
  margin-top: .3rem;
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 14;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 3rem;
  padding-bottom: 3rem;
  border-bottom: 1px solid rgba(250,247,239,.12);
}
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { margin-bottom: .5rem; }

.footer-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  padding-top: 2rem;
  font-size: .82rem;
  color: rgba(250,247,239,.55);
}
.footer-meta a { color: rgba(250,247,239,.55); }
.footer-meta a:hover { color: var(--tall); }

@media (max-width: 900px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
}
@media (max-width: 540px) {
  .footer-grid { grid-template-columns: 1fr; }
}

/* ===========================================================
   ANIMATIONS / FADE-IN
   =========================================================== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
.fade-in.visible { opacity: 1; transform: none; }

.fade-in-delay-1 { transition-delay: .08s; }
.fade-in-delay-2 { transition-delay: .16s; }
.fade-in-delay-3 { transition-delay: .24s; }
.fade-in-delay-4 { transition-delay: .32s; }
.fade-in-delay-5 { transition-delay: .4s; }
.fade-in-delay-6 { transition-delay: .48s; }

@media (prefers-reduced-motion: reduce) {
  .fade-in, .fade-in.visible { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ===========================================================
   ORNAMENTS & DECORATIVE
   =========================================================== */
/* Section divider with centered glyph */
.section-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.2rem;
  margin: 0 auto;
  color: var(--rule);
  padding: 2rem 0;
}
.section-divider::before,
.section-divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}
.section-divider .glyph {
  font-family: var(--font-display);
  color: var(--tall-deep);
  font-size: 1.2rem;
  font-style: italic;
  opacity: .7;
}

/* Corner bracket decoration */
.brackets {
  position: relative;
  padding: 1.5rem;
}
.brackets::before, .brackets::after {
  content: "";
  position: absolute;
  width: 18px; height: 18px;
  border: 1px solid var(--tall-deep);
}
.brackets::before { top: 0; left: 0; border-right: 0; border-bottom: 0; }
.brackets::after { bottom: 0; right: 0; border-left: 0; border-top: 0; }

/* Section numbering */
.sec-num {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1rem;
  color: var(--tall-dark);
  margin-right: .6rem;
  font-variation-settings: "opsz" 14;
}

/* ===========================================================
   HERO-SPECIFIC (index)
   =========================================================== */
.hero {
  padding: clamp(7rem, 12vw, 10rem) 0 clamp(4rem, 7vw, 6rem);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 800px 400px at 80% 10%, rgba(77,178,128,.22), transparent 60%),
    radial-gradient(ellipse 600px 400px at 10% 80%, rgba(182,85,30,.08), transparent 60%);
  pointer-events: none;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: clamp(2rem, 5vw, 5rem);
  align-items: end;
}
@media (max-width: 960px) { .hero-grid { grid-template-columns: 1fr; } }

.hero-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
}
.hero-stats .stat { padding: 1.25rem 1.25rem 1.25rem 0; }

.version-tag {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .4rem 1rem;
  border: 1px solid var(--tall-deep);
  color: var(--tall-deep);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: .8rem;
  font-weight: 500;
  background: rgba(255,255,255,0.4);
  backdrop-filter: blur(6px);
}
.version-tag .dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--tall);
  box-shadow: 0 0 0 4px rgba(77,178,128,.25);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(77,178,128,.25); }
  50% { box-shadow: 0 0 0 7px rgba(77,178,128,0); }
}

/* ===========================================================
   FEATURE GRID / MODULE LIST (paper-based)
   =========================================================== */
.module {
  display: grid;
  grid-template-columns: 60px 1fr;
  gap: 1.25rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--rule);
  transition: background .25s var(--ease);
}
.module:hover { background: rgba(255,255,255,0.4); }
.module-num {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-style: italic;
  color: var(--tall-deep);
  font-variation-settings: "opsz" 14;
}
.module-title {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: 1.35rem;
  color: var(--ink);
  margin-bottom: .4rem;
  font-variation-settings: "opsz" 30;
  letter-spacing: -0.01em;
}
.module-desc { color: var(--ink-soft); line-height: 1.6; }
.module-tags {
  margin-top: .75rem;
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
}

/* ===========================================================
   TIMELINE (conferences, etc.)
   =========================================================== */
.timeline {
  position: relative;
  padding-left: 2rem;
  margin: 0;
  list-style: none;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: .6rem;
  bottom: .6rem;
  width: 1px;
  background: var(--rule);
}
.timeline li {
  position: relative;
  padding: .8rem 0 1.4rem 1.5rem;
}
.timeline li::before {
  content: "";
  position: absolute;
  left: -5px; top: 1.1rem;
  width: 11px; height: 11px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--tall-deep);
}
.timeline .t-date {
  font-family: var(--font-mono);
  font-size: .78rem;
  color: var(--tall-deep);
  letter-spacing: .1em;
  text-transform: uppercase;
  font-weight: 600;
}
.timeline .t-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--ink);
  margin: .1rem 0 .2rem;
  font-variation-settings: "opsz" 30;
}
.timeline .t-sub { font-size: .9rem; color: var(--ink-muted); }

/* ===========================================================
   TEAM
   =========================================================== */
.person {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 6px;
  transition: all .3s var(--ease);
}
.person:hover {
  transform: translateY(-3px);
  box-shadow: 0 30px 60px -40px rgba(15, 26, 20, 0.3);
  border-color: var(--tall);
}
.person-avatar {
  width: 88px;
  height: 88px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
  border: 3px solid var(--paper-warm);
  box-shadow: 0 0 0 1px var(--rule);
}
.person-name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.15rem;
  color: var(--ink);
  line-height: 1.2;
  font-variation-settings: "opsz" 30;
}
.person-role {
  font-size: .88rem;
  color: var(--ink-muted);
  margin: .3rem 0 .7rem;
  line-height: 1.45;
}
.person-links {
  display: flex;
  gap: .6rem;
}
.person-links a {
  width: 30px; height: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: 1px solid var(--rule);
  color: var(--tall-deep);
  transition: all .2s var(--ease);
}
.person-links a:hover {
  background: var(--tall-deep);
  color: var(--paper);
  border-color: var(--tall-deep);
}
.person-links svg { width: 15px; height: 15px; }

/* ===========================================================
   COMPARISON TABLE (vs competitors)
   =========================================================== */
.cmp-table {
  width: 100%;
  border-collapse: collapse;
  font-size: .9rem;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 6px;
  overflow: hidden;
}
.cmp-table th, .cmp-table td {
  padding: .85rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--rule-soft);
}
.cmp-table th {
  font-family: var(--font-body);
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: .74rem;
  font-weight: 700;
  color: var(--ink-muted);
  background: var(--paper-warm);
}
.cmp-table th.col-tall {
  background: var(--tall-deep);
  color: var(--paper);
}
.cmp-table td.cell-yes { color: var(--tall-deep); font-weight: 600; }
.cmp-table td.cell-no { color: var(--ink-muted); }
.cmp-table td.cell-tall { background: rgba(77,178,128,.07); font-weight: 600; color: var(--tall-deep); }
.cmp-table tr:last-child td { border-bottom: 0; }
.cmp-table .section-row td {
  background: var(--paper-warm);
  font-weight: 700;
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--ink);
}

/* ===========================================================
   SCROLLBAR
   =========================================================== */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--paper-warm); }
::-webkit-scrollbar-thumb { background: var(--tall-deep); border-radius: 999px; border: 2px solid var(--paper-warm); }
::-webkit-scrollbar-thumb:hover { background: var(--ink); }

/* ===========================================================
   UTILITY — accent color helpers
   =========================================================== */
.text-ink { color: var(--ink); }
.text-ink-soft { color: var(--ink-soft); }
.text-muted { color: var(--ink-muted); }
.text-tall { color: var(--tall-deep); }
.text-amber { color: var(--amber); }

.bg-paper { background: var(--paper); }
.bg-warm { background: var(--paper-warm); }
.bg-deep { background: var(--paper-deep); }
.bg-ink { background: var(--ink); color: var(--paper); }
.bg-tall-deep { background: var(--tall-deep); color: var(--paper); }
.bg-surface { background: var(--surface); }

/* Cross-page figure emphasis */
.fig-frame {
  padding: .5rem;
  background: var(--paper-warm);
  border: 1px solid var(--rule);
  border-radius: 8px;
  display: inline-block;
}
.fig-frame img { border-radius: 4px; border: 1px solid var(--rule-soft); }

/* ===========================================================
   DOI BLOCK (paper citation)
   =========================================================== */
.doi-block {
  display: inline-flex;
  flex-direction: column;
  gap: .3rem;
  padding: .85rem 1.2rem;
  background: var(--paper-warm);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--tall-deep);
  border-radius: 4px;
  max-width: 100%;
}
.doi-label {
  font-family: var(--font-body);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--ink-muted);
}
.doi-link {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  font-family: var(--font-mono);
  font-size: .92rem;
  font-weight: 500;
  color: var(--tall-deep);
  word-break: break-all;
}
.doi-link:hover { color: var(--ink); }
.doi-link svg { width: 16px; height: 16px; flex-shrink: 0; }

/* ===========================================================
   ACCORDION (supplementary material sections)
   =========================================================== */
.accordion {
  display: flex;
  flex-direction: column;
  gap: .75rem;
}

.acc-item {
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 8px;
  overflow: hidden;
  transition: border-color .25s var(--ease), box-shadow .3s var(--ease);
}
.acc-item:hover { border-color: var(--tall); }
.acc-item[open] {
  border-color: var(--tall-deep);
  box-shadow: 0 20px 50px -30px rgba(15, 61, 42, 0.25);
}

/* Remove default disclosure triangle */
.acc-head {
  list-style: none;
  cursor: pointer;
  padding: 1.25rem 1.5rem;
  display: grid;
  grid-template-columns: 44px 1fr auto 20px;
  align-items: center;
  gap: 1.1rem;
  user-select: none;
  transition: background .25s var(--ease);
}
.acc-head::-webkit-details-marker { display: none; }
.acc-head::marker { content: ""; }
.acc-head:hover { background: var(--paper-warm); }
.acc-item[open] .acc-head { background: var(--paper-warm); border-bottom: 1px solid var(--rule); }

.acc-letter {
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.3rem;
  color: var(--tall-deep);
  background: var(--tall-soft);
  border-radius: 50%;
  font-variation-settings: "opsz" 30;
  transition: background .25s var(--ease), color .25s var(--ease);
}
.acc-item[open] .acc-letter {
  background: var(--tall-deep);
  color: var(--paper);
}

.acc-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 550;
  color: var(--ink);
  font-variation-settings: "opsz" 30;
  letter-spacing: -.005em;
  line-height: 1.25;
}

.acc-meta {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-muted);
  white-space: nowrap;
}

.acc-chev {
  width: 20px;
  height: 20px;
  color: var(--ink-muted);
  transition: transform .3s var(--ease), color .25s var(--ease);
}
.acc-item[open] .acc-chev {
  transform: rotate(180deg);
  color: var(--tall-deep);
}

.acc-body {
  padding: 1.5rem 1.5rem 1.75rem;
  animation: accOpen .35s var(--ease);
}
@keyframes accOpen {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: none; }
}

.acc-body p:last-child { margin-bottom: 0; }

@media (max-width: 640px) {
  .acc-head {
    grid-template-columns: 38px 1fr 18px;
    grid-template-rows: auto auto;
    padding: 1rem 1.1rem;
    gap: .8rem;
  }
  .acc-letter { width: 34px; height: 34px; font-size: 1.15rem; }
  .acc-title { grid-column: 2; }
  .acc-meta { grid-column: 2 / span 2; font-size: .68rem; margin-top: .1rem; }
  .acc-chev { grid-column: 3; grid-row: 1; }
  .acc-body { padding: 1.1rem; }
}

/* ===========================================================
   ACCORDION CONTENT HELPERS
   =========================================================== */
/* Package grid (section A) */
.pkg-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
}
.pkg-cat {
  font-family: var(--font-body);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--tall-deep);
  margin-bottom: .5rem;
}
.pkg-list { display: flex; flex-wrap: wrap; gap: .35rem; }

/* FAIR grid (section B) */
.fair-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1rem;
}
.fair-card {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 1rem;
  padding: 1.1rem 1.2rem;
  background: var(--paper-warm);
  border-radius: 6px;
  border: 1px solid var(--rule-soft);
}
.fair-letter {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.5rem;
  color: var(--paper);
  background: var(--tall-deep);
  border-radius: 50%;
  font-variation-settings: "opsz" 96;
}
.fair-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--ink);
  margin-bottom: .4rem;
  font-variation-settings: "opsz" 30;
}
.fair-desc {
  font-size: .88rem;
  line-height: 1.65;
  color: var(--ink-soft);
}

/* Architecture layers (section C) */
.arch-layers {
  list-style: none;
  counter-reset: arch;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: .85rem;
}
.arch-layers li {
  counter-increment: arch;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 1rem;
  padding: 1rem 1.2rem;
  background: var(--paper-warm);
  border-radius: 6px;
  border: 1px solid var(--rule-soft);
  position: relative;
}
.arch-layers li::before {
  content: counter(arch);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--tall-deep);
  color: var(--paper);
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.05rem;
  font-variation-settings: "opsz" 30;
}
.arch-layers li > div { min-width: 0; }
.arch-layers .arch-head {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--ink);
  margin-bottom: .25rem;
  font-variation-settings: "opsz" 30;
  letter-spacing: -.005em;
  line-height: 1.3;
}
.arch-layers .arch-desc {
  margin: 0;
  color: var(--ink-soft);
  line-height: 1.6;
}
.arch-layers .arch-desc code {
  font-family: var(--font-mono);
  font-size: .9em;
  background: var(--surface);
  padding: .05em .35em;
  border-radius: 3px;
  border: 1px solid var(--rule-soft);
}

/* Step list (section F) */
.step-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: .6rem;
}
.step-list li {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 1rem;
  padding: .85rem 1.1rem;
  background: var(--paper-warm);
  border-radius: 6px;
  border: 1px solid var(--rule-soft);
  align-items: start;
}
.step-list .step-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--tall-deep);
  color: var(--paper);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: .95rem;
  font-variation-settings: "opsz" 14;
  flex-shrink: 0;
}
.step-list .step-head {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--ink);
  margin-bottom: .25rem;
  font-variation-settings: "opsz" 30;
  letter-spacing: -.005em;
  line-height: 1.3;
}
.step-list .step-desc {
  margin: 0;
  color: var(--ink-soft);
  line-height: 1.6;
}
.step-list .step-desc b,
.step-list .step-desc strong {
  font-weight: 700;
  color: var(--ink);
}

/* ===========================================================
   LIGHTBOX — click figure images to enlarge
   =========================================================== */
.figure img,
.fig-frame img {
  cursor: zoom-in;
  transition: filter .25s var(--ease), box-shadow .25s var(--ease);
}
.figure img:hover,
.fig-frame img:hover {
  filter: brightness(1.03);
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(10, 15, 12, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(1rem, 3vw, 2.5rem);
  opacity: 0;
  pointer-events: none;
  transition: opacity .3s var(--ease);
}
.lightbox.open {
  opacity: 1;
  pointer-events: auto;
}

.lightbox-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
  max-width: 100%;
  max-height: 100%;
}

.lightbox img {
  max-width: 95vw;
  max-height: 82vh;
  object-fit: contain;
  border-radius: 4px;
  background: var(--surface);
  box-shadow: 0 40px 100px -20px rgba(0,0,0,.7);
  transform: scale(.96);
  transition: transform .35s var(--ease);
  cursor: zoom-out;
}
.lightbox.open img {
  transform: scale(1);
}

.lightbox-caption {
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 14;
  color: rgba(250, 247, 239, 0.82);
  text-align: center;
  max-width: 62em;
  font-size: .95rem;
  line-height: 1.55;
}
.lightbox-caption strong {
  font-family: var(--font-body);
  font-style: normal;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  font-size: .72rem;
  color: var(--tall);
  margin-right: .5rem;
}
.lightbox-caption:empty { display: none; }

.lightbox-close {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 1px solid rgba(250,247,239,.25);
  background: rgba(250,247,239,.06);
  color: var(--paper);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: background .2s var(--ease), border-color .2s var(--ease), transform .2s var(--ease);
  z-index: 1;
}
.lightbox-close:hover {
  background: var(--paper);
  color: var(--ink);
  border-color: var(--paper);
  transform: scale(1.05);
}
.lightbox-close svg { width: 20px; height: 20px; }

.lightbox-hint {
  position: fixed;
  bottom: 1.25rem;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: rgba(250,247,239,.5);
  text-transform: uppercase;
  pointer-events: none;
}
.lightbox-hint kbd {
  font-family: var(--font-mono);
  padding: .15rem .4rem;
  border: 1px solid rgba(250,247,239,.25);
  border-radius: 3px;
  margin: 0 .2rem;
  color: rgba(250,247,239,.75);
}

body.lightbox-open { overflow: hidden; }

@media (max-width: 640px) {
  .lightbox-hint { display: none; }
  .lightbox-close { top: 1rem; right: 1rem; width: 40px; height: 40px; }
}