/* ═══ COLOR FLOW MAP (from design-spec.sections[].bg_context) ═══
 *
 * index.html:
 *   nav        → transparent-on-dark (scrolled: solid #0A0F1A)
 *   hero       → DARK  (#0A0F1A)       | text: #F0F4F8 / #F97316
 *   problem    → DARK_ALT (#0F1829)    | text: #F0F4F8
 *   what-we-do → DARK_SURFACE (#141E30)| text: #F0F4F8
 *   differ     → DARK (#0A0F1A)        | text: #F0F4F8
 *   platform   → DARK_ALT (#0F1829)    | text: #F0F4F8
 *   customers  → DARK_SURFACE (#141E30)| text: #F0F4F8
 *   cta-band   → DARK (#0A0F1A)        | text: #F0F4F8
 *   footer     → DARK (#0A0F1A)        | text: #94A3B8 / #F0F4F8
 *
 * technology/index.html: dark-top — all dark sections
 * architecture/index.html: dark-top — all dark sections
 *
 * evaluation/index.html:
 *   nav        → transparent-on-light → forced solid dark
 *   hero       → LIGHT (#F8FAFC)       | text: #0A0F1A
 *   process    → LIGHT_ALT (#EEF2F7)   | text: #0A0F1A
 *   form       → WHITE (#FFFFFF)       | text: #0A0F1A
 *   faq        → LIGHT (#F8FAFC)       | text: #0A0F1A
 *   footer     → DARK (#0A0F1A)        | text: #94A3B8
 *
 * customers/index.html: light-top (all light/white sections)
 * about/index.html: dark-top (all dark sections)
 * team/index.html: light-top (light/white sections)
 * careers/index.html: light-top
 * contact/index.html: light-top
 * blog/index.html: light-top
 * blog articles: light-top
 * login pages: dark-top
 * legal pages: light-top
 *
 * Nav notes:
 *   dark-top pages → nav transparent-at-top (white/amber text), scrolled→solid #0A0F1A
 *   light-top pages → nav always solid #0A0F1A (forced-dark), white text
 *   Logo: dark-top → logo-light.svg; light-top → logo-dark.svg
 *   Adjacent dark→dark sections: distinguish via bg shade step
 * ═══════════════════════════════════════════════════════════════ */

/* === CSS CUSTOM PROPERTIES === */
:root {
  /* Brand palette */
  --pcu-bg-dark:         #0A0F1A;
  --pcu-bg-dark-alt:     #0F1829;
  --pcu-bg-dark-surface: #141E30;
  --pcu-bg-light:        #F8FAFC;
  --pcu-bg-light-alt:    #EEF2F7;
  --pcu-bg-white:        #FFFFFF;

  /* Foreground tokens */
  --pcu-fg-dark-primary:   #F0F4F8;
  --pcu-fg-dark-secondary: #94A3B8;
  --pcu-fg-light-primary:  #0A0F1A;
  --pcu-fg-light-secondary:#4B5563;

  /* Accent */
  --pcu-accent:           #F97316;
  --pcu-accent-aa-dark:   #F97316;
  --pcu-accent-aa-light:  #C05A08;

  /* Border */
  --pcu-border-dark:      rgba(255,255,255,0.08);
  --pcu-border-light:     rgba(10,15,26,0.12);

  /* Typography */
  --pcu-font-mono:  'IBM Plex Mono', 'Courier New', monospace;
  --pcu-font-body:  'Inter', system-ui, sans-serif;

  /* Spacing */
  --pcu-section-pad: clamp(80px, 10vw, 140px);
  --pcu-container:   1200px;
  --pcu-nav-h:       72px;
}

/* === RESET & BASE === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--pcu-font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--pcu-fg-light-primary);
  background: var(--pcu-bg-white);
}

body.pcu-page--dark-top {
  background: var(--pcu-bg-dark);
}

img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; }
ul, ol { list-style: none; }
button { cursor: pointer; font-family: inherit; }

/* === TYPOGRAPHY BASE === */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--pcu-font-mono);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

/* On dark bg */
.pcu-section--dark h1,
.pcu-section--dark-alt h1,
.pcu-section--dark-surface h1,
.pcu-hero h1 {
  color: var(--pcu-fg-dark-primary);
}

/* === CONTAINER === */
.pcu-container {
  max-width: var(--pcu-container);
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 60px);
}

/* === NAVIGATION === */
.pcu-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--pcu-nav-h);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

/* Dark-top pages: transparent initially, logo-light */
body.pcu-page--dark-top .pcu-nav {
  background: transparent;
}

body.pcu-page--dark-top .pcu-nav--scrolled,
body.pcu-page--light-top .pcu-nav {
  background: var(--pcu-bg-dark);
  box-shadow: 0 1px 0 rgba(255,255,255,0.06);
}

/* Transparent nav must not let body-white show through on dark pages */
body.pcu-page--dark-top .pcu-nav::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(10,15,26,0.5) 0%, transparent 100%);
  pointer-events: none;
  z-index: -1;
  opacity: 1;
  transition: opacity 0.3s ease;
}

body.pcu-page--dark-top .pcu-nav--scrolled::before {
  opacity: 0;
}

.pcu-nav__inner {
  max-width: var(--pcu-container);
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 60px);
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}

.pcu-nav__logo {
  flex-shrink: 0;
  display: flex;
  align-items: center;
}

.pcu-nav__logo img {
  height: 32px;
  width: auto;
  max-width: 180px;
}

.pcu-nav__links {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  justify-content: center;
}

.pcu-nav__link {
  font-size: 0.9rem;
  font-weight: 500;
  color: rgba(240,244,248,0.85);
  padding: 8px 12px;
  border-radius: 6px;
  transition: color 0.2s, background 0.2s;
  white-space: nowrap;
}

.pcu-nav__link:hover {
  color: #F0F4F8;
  background: rgba(255,255,255,0.06);
}

.pcu-nav__actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.pcu-nav__sign-in {
  font-size: 0.875rem;
  font-weight: 500;
  color: rgba(240,244,248,0.75);
  padding: 8px 14px;
  border-radius: 6px;
  transition: color 0.2s, background 0.2s;
}

.pcu-nav__sign-in:hover {
  color: #F0F4F8;
  background: rgba(255,255,255,0.06);
}

/* Mobile hamburger */
.pcu-nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: transparent;
  border: none;
  padding: 8px;
  margin-left: auto;
}

.pcu-nav__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--pcu-fg-dark-primary);
  border-radius: 2px;
  transition: transform 0.2s, opacity 0.2s;
}

/* Mobile menu */
.pcu-nav__mobile-menu {
  display: none;
  position: fixed;
  top: var(--pcu-nav-h);
  left: 0;
  right: 0;
  background: var(--pcu-bg-dark);
  padding: 20px;
  border-top: 1px solid var(--pcu-border-dark);
  flex-direction: column;
  gap: 4px;
  z-index: 99;
}

.pcu-nav__mobile-menu.is-open {
  display: flex;
}

.pcu-nav__mobile-menu a {
  display: block;
  color: var(--pcu-fg-dark-primary);
  font-size: 1rem;
  font-weight: 500;
  padding: 12px 16px;
  border-radius: 8px;
  transition: background 0.15s;
}

.pcu-nav__mobile-menu a:hover {
  background: rgba(255,255,255,0.06);
}

/* === BUTTONS === */
.pcu-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--pcu-font-body);
  font-size: 0.9rem;
  font-weight: 600;
  padding: 11px 24px;
  border-radius: 8px;
  border: none;
  transition: all 0.2s ease;
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
}

.pcu-btn--primary {
  background: var(--pcu-accent);
  color: #0A0F1A;
}

.pcu-btn--primary:hover {
  background: #fb923c;
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(249,115,22,0.35);
}

.pcu-btn--outline-dark {
  background: transparent;
  border: 1px solid rgba(240,244,248,0.3);
  color: var(--pcu-fg-dark-primary);
}

.pcu-btn--outline-dark:hover {
  border-color: rgba(240,244,248,0.6);
  background: rgba(255,255,255,0.05);
}

.pcu-btn--outline-light {
  background: transparent;
  border: 1px solid rgba(10,15,26,0.25);
  color: var(--pcu-fg-light-primary);
}

.pcu-btn--outline-light:hover {
  border-color: rgba(10,15,26,0.5);
  background: rgba(10,15,26,0.04);
}

.pcu-btn--sm {
  font-size: 0.8rem;
  padding: 8px 16px;
}

/* === SECTIONS === */
.pcu-section--dark {
  background: var(--pcu-bg-dark);
  color: var(--pcu-fg-dark-primary);
}

.pcu-section--dark-alt {
  background: var(--pcu-bg-dark-alt);
  color: var(--pcu-fg-dark-primary);
}

.pcu-section--dark-surface {
  background: var(--pcu-bg-dark-surface);
  color: var(--pcu-fg-dark-primary);
}

.pcu-section--light {
  background: var(--pcu-bg-light);
  color: var(--pcu-fg-light-primary);
}

.pcu-section--light-alt {
  background: var(--pcu-bg-light-alt);
  color: var(--pcu-fg-light-primary);
}

.pcu-section--white {
  background: var(--pcu-bg-white);
  color: var(--pcu-fg-light-primary);
}

/* === SECTION PADDING === */
.pcu-section {
  padding: var(--pcu-section-pad) 0;
}

/* === EYEBROW LABELS === */
.pcu-eyebrow {
  font-family: var(--pcu-font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  display: block;
  margin-bottom: 16px;
}

.pcu-section--dark .pcu-eyebrow,
.pcu-section--dark-alt .pcu-eyebrow,
.pcu-section--dark-surface .pcu-eyebrow,
.pcu-hero .pcu-eyebrow {
  color: var(--pcu-accent-aa-dark);
}

.pcu-section--light .pcu-eyebrow,
.pcu-section--light-alt .pcu-eyebrow,
.pcu-section--white .pcu-eyebrow {
  color: var(--pcu-accent-aa-light);
}

/* === SECTION HEADINGS === */
.pcu-section--dark .pcu-section__heading,
.pcu-section--dark-alt .pcu-section__heading,
.pcu-section--dark-surface .pcu-section__heading {
  font-family: var(--pcu-font-mono);
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  color: var(--pcu-fg-dark-primary);
  margin-bottom: 20px;
}

.pcu-section--light .pcu-section__heading,
.pcu-section--light-alt .pcu-section__heading,
.pcu-section--white .pcu-section__heading {
  font-family: var(--pcu-font-mono);
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  color: var(--pcu-fg-light-primary);
  margin-bottom: 20px;
}

.pcu-section--dark .pcu-section__subhead,
.pcu-section--dark-alt .pcu-section__subhead,
.pcu-section--dark-surface .pcu-section__subhead {
  font-size: 1.05rem;
  color: var(--pcu-fg-dark-secondary);
  line-height: 1.7;
  max-width: 640px;
}

.pcu-section--light .pcu-section__subhead,
.pcu-section--light-alt .pcu-section__subhead,
.pcu-section--white .pcu-section__subhead {
  font-size: 1.05rem;
  color: var(--pcu-fg-light-secondary);
  line-height: 1.7;
  max-width: 640px;
}

/* === FOOTER === */
.pcu-footer {
  background: var(--pcu-bg-dark);
  color: var(--pcu-fg-dark-secondary);
  padding: 72px 0 36px;
  border-top: 1px solid var(--pcu-border-dark);
}

.pcu-footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 60px;
  margin-bottom: 48px;
}

.pcu-footer__logo img {
  height: 28px;
  width: auto;
  max-width: 160px;
  margin-bottom: 16px;
}

.pcu-footer__tagline {
  font-size: 0.875rem;
  color: var(--pcu-fg-dark-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
}

.pcu-footer__contact {
  font-size: 0.8rem;
  line-height: 1.8;
  color: var(--pcu-fg-dark-secondary);
}

.pcu-footer__contact a {
  color: var(--pcu-fg-dark-secondary);
  transition: color 0.2s;
}

.pcu-footer__contact a:hover {
  color: var(--pcu-fg-dark-primary);
}

.pcu-footer__col-title {
  font-family: var(--pcu-font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--pcu-fg-dark-primary);
  margin-bottom: 16px;
}

.pcu-footer__col-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.pcu-footer__col-links a {
  font-size: 0.875rem;
  color: var(--pcu-fg-dark-secondary);
  transition: color 0.2s;
}

.pcu-footer__col-links a:hover {
  color: var(--pcu-fg-dark-primary);
}

.pcu-footer__divider {
  border: none;
  border-top: 1px solid var(--pcu-border-dark);
  margin-bottom: 28px;
}

.pcu-footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.pcu-footer__copy {
  font-size: 0.8rem;
  color: var(--pcu-fg-dark-secondary);
  opacity: 0.7;
}

.pcu-footer__cookie-prefs {
  font-size: 0.8rem;
  color: var(--pcu-fg-dark-secondary);
  transition: color 0.2s;
}

.pcu-footer__cookie-prefs:hover {
  color: var(--pcu-fg-dark-primary);
}

/* === COOKIE BANNER === */
.cookie-banner,
.cookie-banner--notice {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background: var(--pcu-bg-dark-surface);
  border-top: 1px solid var(--pcu-border-dark);
  padding: 16px 24px;
}

.cookie-banner__actions {
  display: flex;
  gap: 8px;
  flex-shrink: 0;
}

.cookie-banner__inner {
  max-width: var(--pcu-container);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: space-between;
}

.cookie-banner__text {
  font-size: 0.875rem;
  color: var(--pcu-fg-dark-secondary);
  flex: 1;
  min-width: 240px;
}

.cookie-banner__text a {
  color: var(--pcu-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.cookie-banner__btn {
  font-family: var(--pcu-font-body);
  font-size: 0.875rem;
  font-weight: 600;
  padding: 9px 20px;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  white-space: nowrap;
}

.cookie-banner__btn--primary {
  background: var(--pcu-accent);
  color: #0A0F1A;
}

.cookie-banner__btn--primary:hover {
  background: #fb923c;
}

/* === FADE-IN === */
.pcu-fade-in {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.pcu-fade-in.is-visible {
  opacity: 1;
  transform: none;
}

/* === CARD BASE === */
.pcu-card {
  border-radius: 12px;
  padding: 32px;
}

.pcu-section--dark .pcu-card,
.pcu-section--dark-alt .pcu-card,
.pcu-section--dark-surface .pcu-card {
  background: var(--pcu-bg-dark-surface);
  border: 1px solid var(--pcu-border-dark);
}

.pcu-section--light .pcu-card,
.pcu-section--light-alt .pcu-card,
.pcu-section--white .pcu-card {
  background: var(--pcu-bg-white);
  border: 1px solid var(--pcu-border-light);
  box-shadow: 0 2px 12px rgba(10,15,26,0.05);
}

/* === GRID LAYOUTS === */
.pcu-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.pcu-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

/* === RESPONSIVE === */
@media (max-width: 1024px) {
  .pcu-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .pcu-grid-2 { grid-template-columns: 1fr; gap: 32px; }
  .pcu-footer__grid { grid-template-columns: 1fr 1fr; gap: 40px; }
}

@media (max-width: 768px) {
  .pcu-nav__links { display: none; }
  .pcu-nav__actions { display: none; }
  .pcu-nav__hamburger { display: flex; }
  .pcu-grid-3 { grid-template-columns: 1fr; }
  .pcu-footer__grid { grid-template-columns: 1fr; gap: 32px; }
}