/* ============================================================
   VALUEAXIS — DESIGN SYSTEM  ·  system.css
   ============================================================ */

/* ── 1. DESIGN TOKENS ── */
:root {
  --canvas:          #FAFAF9;
  --canvas-2:        #F5F5F4;
  --canvas-3:        #EFEEEC;
  --ink:             #1C1917;
  --ink-2:           #78716C;
  --ink-3:           #A8A29E;
  --line:            #E7E5E4;
  --amber:           #F59E0B;
  --amber-light:     #FEF3C7;
  --indigo:          #3730A3;
  --indigo-bg:       #EEF2FF;
  --indigo-border:   #C7D2FE;

  --sans: 'Inter', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', 'Fira Mono', ui-monospace, monospace;

  --radius:       6px;
  --radius-lg:    12px;
  --section-pad:  clamp(72px, 9vw, 128px);
  --wrap-max:     1200px;
  --wrap-px:      clamp(20px, 5vw, 80px);
}

/* ── 2. RESET + BASE ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
body {
  font-family: var(--sans);
  background: var(--canvas);
  color: var(--ink);
  line-height: 1.6;
}
a          { color: inherit; text-decoration: none; }
img, svg   { display: block; max-width: 100%; }
ul, ol     { list-style: none; }
button     { font-family: var(--sans); cursor: pointer; border: none; background: none; }
h1,h2,h3,h4,h5,h6 { font-weight: 700; line-height: 1.12; }

/* ── 3. TYPOGRAPHY ── */
.display {
  font-size: clamp(2.375rem, 5.2vw, 4.5rem);
  font-weight: 800;
  line-height: 1.04;
  letter-spacing: -0.025em;
}
.display-2 {
  font-size: clamp(1.875rem, 3.8vw, 3.125rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.h1 {
  font-size: clamp(1.5rem, 2.6vw, 2.25rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.015em;
}
.lead {
  font-size: clamp(1rem, 1.4vw, 1.1875rem);
  line-height: 1.7;
  color: var(--ink-2);
}
.body-lg {
  font-size: clamp(0.9375rem, 1.1vw, 1.0625rem);
  line-height: 1.65;
}
.eyebrow {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-2);
}
.small {
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--ink-2);
}
.mono {
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--ink-2);
}
.amber  { color: var(--amber); }
.muted  { color: var(--ink-2); }
.center { text-align: center; }

/* ── 4. LAYOUT PRIMITIVES ── */
.wrap {
  max-width: var(--wrap-max);
  margin: 0 auto;
  padding: 0 var(--wrap-px);
}
.wrap-narrow {
  max-width: 700px;
  margin: 0 auto;
  padding: 0 var(--wrap-px);
}
section {
  padding: var(--section-pad) 0;
}
section.tight {
  padding: clamp(44px, 5.5vw, 72px) 0;
}
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(28px, 4.5vw, 64px);
  align-items: start;
}
.col   { display: flex; flex-direction: column; }
.flex  { display: flex; align-items: center; flex-wrap: wrap; }
.gap-8  { gap: 8px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }
.gap-32 { gap: 32px; }
.mt-24  { margin-top: 24px; }
.mt-32  { margin-top: 32px; }
.mb-8   { margin-bottom: 8px; }
.mb-16  { margin-bottom: 16px; }
.mb-48  { margin-bottom: 48px; }
.rule   { height: 1px; background: var(--line); width: 100%; }

/* ── 5. NAVIGATION ── */

/* Thin indigo accent at very top of page */
html {
  border-top: 3px solid var(--indigo);
}

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--canvas);
  border-bottom: 1px solid var(--line);
  transition: box-shadow 0.25s;
}
.nav.scrolled {
  box-shadow: 0 2px 20px rgba(28,25,23,0.09);
}
.nav-inner {
  max-width: var(--wrap-max);
  margin: 0 auto;
  padding: 0 var(--wrap-px);
  height: 66px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.wm {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--ink);
  text-transform: uppercase;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(14px, 1.8vw, 26px);
  flex-shrink: 1;
}
.nav-links a {
  font-size: 0.8125rem;
  color: var(--ink-2);
  white-space: nowrap;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--indigo); }
.btn-text {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--indigo);
  white-space: nowrap;
  flex-shrink: 0;
  transition: opacity 0.15s;
}
.btn-text:hover { opacity: 0.7; }
.arr {
  display: inline-block;
  transition: transform 0.18s ease;
}
.btn-text:hover .arr,
.btn:hover .arr { transform: translateX(3px); }

/* ── 6. BUTTONS ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius);
  border: 1.5px solid transparent;
  transition: all 0.15s;
  white-space: nowrap;
  cursor: pointer;
}
.btn-primary {
  background: var(--indigo);
  color: #fff;
  border-color: var(--indigo);
}
.btn-primary:hover { opacity: 0.88; }
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
}
.btn-ghost:hover { border-color: var(--indigo); color: var(--indigo); }
.btn-amber {
  background: var(--amber);
  color: var(--ink);
  border-color: var(--amber);
  font-weight: 600;
}
.btn-amber:hover { filter: brightness(1.06); }

/* ── 7. HERO ── */
.hero {
  padding: clamp(60px, 8.5vw, 112px) 0 clamp(32px, 4vw, 56px);
  border-bottom: 1px solid var(--line);
  border-top: 3px solid var(--indigo);
}
.hero-meta {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-bottom: clamp(32px, 5vw, 56px);
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}
.hero-meta .num,
.hero-meta .label,
.hero-meta .date {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.hero-meta .num {
  color: var(--indigo);
  font-weight: 500;
}
.hero-meta .date { margin-left: auto; }

/* ── 8. FOOTNOTE BAR ── */
.footnote-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 0;
  border-top: 1px solid var(--line);
  padding-top: 18px;
}
.footnote-bar span {
  font-family: var(--mono);
  font-size: 0.625rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-3);
  padding-right: 28px;
}

/* ── 9. CHAPTER LAYOUT ── */
.chapter {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 0 56px;
  align-items: start;
}
.chapter-num {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--indigo);
  opacity: 0.7;
  padding-top: 6px;
  position: sticky;
  top: 78px;
  line-height: 1.5;
}
.chapter-body {}

/* ── 10. CATALOGUE LIST ROWS ── */
.list-rows {
  border-top: 1px solid var(--line);
}
.list-row {
  display: grid;
  grid-template-columns: 68px 190px 1fr 110px;
  gap: 0 28px;
  align-items: start;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  cursor: pointer;
  transition: background 0.14s, padding 0.14s;
}
.list-row:hover {
  background: var(--indigo-bg);
  padding-left: 14px;
  padding-right: 14px;
  margin: 0 -14px;
}
.lr-num {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  color: var(--indigo);
  padding-top: 2px;
}
.lr-title {
  font-size: 0.9375rem;
  font-weight: 600;
}
.lr-title + .mono {
  margin-top: 5px;
  font-size: 0.75rem;
}
.lr-desc {
  font-size: 0.875rem;
  color: var(--ink-2);
  line-height: 1.55;
}
.lr-meta {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.04em;
  color: var(--indigo);
  text-align: right;
  padding-top: 2px;
  white-space: nowrap;
}

/* ── 11. DARKROOM (dark sections) ── */
.darkroom {
  background: var(--ink);
  color: var(--canvas);
}
.darkroom .chapter-num   { color: #57534E; opacity: 1; }
.darkroom .display-2     { color: var(--canvas); }
.darkroom .h1            { color: var(--canvas); }
.darkroom .lead          { color: rgba(250,250,249,0.65); }
.darkroom .eyebrow       { color: rgba(250,250,249,0.38); }
.darkroom .small         { color: rgba(250,250,249,0.4); }
.darkroom .mono          { color: rgba(250,250,249,0.4); }
.darkroom .btn-text      { color: var(--canvas); }

/* ── 12. MARQUEE (scrolling client / partner list) ── */
.marquee {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line);
}
.marquee > div {
  display: flex;
  align-items: baseline;
  gap: 20px;
  padding: 17px 0;
  border-bottom: 1px solid var(--line);
  font-size: 1.0625rem;
  font-weight: 500;
  color: var(--ink);
}
.role {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-3);
}
/* Dark context overrides */
.darkroom .marquee                { border-top-color: rgba(255,255,255,0.1); }
.darkroom .marquee > div          { border-bottom-color: rgba(255,255,255,0.07); color: var(--canvas); }
.darkroom .role                   { color: rgba(250,250,249,0.38); }

/* ── 13. LEDGER (stats grid) ── */
.ledger {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid rgba(255,255,255,0.1);
}
.ledger > div {
  padding: 28px 24px 28px 0;
  border-right: 1px solid rgba(255,255,255,0.08);
}
.ledger > div:last-child { border-right: none; }
.ledger .num {
  font-size: clamp(1.875rem, 3vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--canvas);
}
.ledger .unit {
  font-size: 0.8em;
  font-weight: 400;
  margin-left: 3px;
  opacity: 0.6;
}
.ledger .label {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: rgba(250,250,249,0.4);
  margin-top: 10px;
  line-height: 1.5;
}

/* ── 14. SPEC TABLE (approach steps) ── */
.spec { border-top: 1px solid var(--line); }
.spec-row {
  display: grid;
  grid-template-columns: 192px 1fr 136px;
  gap: 0 36px;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
  align-items: start;
}
.spec-row .k {
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--indigo);
}
.spec-row .v {
  font-size: 0.9375rem;
  color: var(--ink-2);
  line-height: 1.65;
}
.spec-row .meta {
  font-family: var(--mono);
  font-size: 0.625rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--indigo);
  text-align: right;
  padding-top: 4px;
  white-space: nowrap;
}

/* ── 15. STACK DIAGRAM ── */
.stack {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.stack-row {
  display: grid;
  grid-template-columns: 152px 1fr;
  border-bottom: 1px solid var(--line);
}
.stack-row:last-child { border-bottom: none; }
.sl-label {
  padding: 14px 18px;
  font-family: var(--mono);
  font-size: 0.5625rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-2);
  background: var(--canvas-2);
  border-right: 1px solid var(--line);
  display: flex;
  align-items: center;
  line-height: 1.4;
}
.sl-label-vax {
  background: var(--indigo-bg);
  color: var(--indigo);
  font-weight: 600;
}
.sl-cells {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 10px 14px;
  background: #fff;
  align-items: center;
}
.sl-cell {
  font-size: 0.8125rem;
  padding: 4px 9px;
  background: var(--canvas-2);
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--ink-2);
  white-space: nowrap;
}
.sl-vax {
  background: var(--indigo-bg);
  border-color: var(--indigo-border);
  color: var(--indigo);
  font-weight: 500;
}
.stack-vax .sl-cells { background: #f5f7ff; }

/* ── 16. FOOTER ── */
.footer {
  background: var(--ink);
  color: rgba(250,250,249,0.6);
  padding: clamp(52px, 7vw, 88px) 0 40px;
}
.f-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 0 48px;
  padding-bottom: 52px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}
.footer h6 {
  font-family: var(--mono);
  font-size: 0.5625rem;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: rgba(250,250,249,0.32);
  margin-bottom: 18px;
  font-weight: 400;
}
.footer ul { display: flex; flex-direction: column; gap: 11px; }
.footer li a {
  font-size: 0.875rem;
  color: rgba(250,250,249,0.6);
  transition: color 0.15s;
}
.footer li a:hover { color: #fff; }
.footer .nav-logo .wm { color: #fff; }
.footer .small,
.footer .mono { color: rgba(250,250,249,0.38); }
.f-base {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 28px;
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  color: rgba(250,250,249,0.28);
}

/* ── 17. RESPONSIVE ── */
@media (max-width: 1024px) {
  .chapter { grid-template-columns: 140px 1fr; gap: 0 28px; }
  .f-grid  { grid-template-columns: 1fr 1fr 1fr; row-gap: 36px; }
  .ledger  { grid-template-columns: 1fr 1fr; }
  .ledger > div:nth-child(2) { border-right: none; }
  .ledger > div:nth-child(3),
  .ledger > div:nth-child(4) { border-top: 1px solid rgba(255,255,255,0.08); }
}

@media (max-width: 800px) {
  :root { --section-pad: clamp(56px, 8vw, 88px); }
  .two-col       { grid-template-columns: 1fr; }
  .chapter       { grid-template-columns: 1fr; gap: 10px 0; }
  .chapter-num   { position: static; }
  .nav-links     { display: none; }
  .list-row      { grid-template-columns: 56px 1fr; }
  .list-row .lr-desc,
  .list-row .lr-meta { display: none; }
  .spec-row      { grid-template-columns: 1fr; gap: 8px 0; }
  .spec-row .meta { text-align: left; }
  .stack-row     { grid-template-columns: 96px 1fr; }
  .f-grid        { grid-template-columns: 1fr 1fr; row-gap: 32px; }
}

@media (max-width: 520px) {
  .f-grid    { grid-template-columns: 1fr; }
  .f-base    { flex-direction: column; gap: 8px; text-align: center; }
  .ledger    { grid-template-columns: 1fr; }
  .ledger > div { border-right: none; border-top: 1px solid rgba(255,255,255,0.08); }
  .ledger > div:first-child { border-top: none; }
}