/* ============================================
   Design Tokens
   ============================================ */
:root {
  /* Colors */
  --warm-bg: #faf8f6;
  --text-primary: #1a0f08;
  --text-secondary: #5c483a;
  --text-tertiary: #8a7568;
  --accent: #c96844;
  --border: rgba(140, 117, 104, 0.12);

  /* Surfaces */
  --surface-dark: #000;
  --surface-overlay: rgba(250, 248, 246, 0.98);
  --surface-nav: rgba(250, 248, 246, 0.95);

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 2.5rem;
  --space-3xl: 4rem;

  /* Layout */
  --content-max-width: 720px;
  --page-padding: 4%;
  --nav-height: 4rem;

  /* Radii */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;

  /* Shadows */
  --shadow-dropdown: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-dropdown-rich: 0 8px 32px rgba(0, 0, 0, 0.12);

  /* Z-index scale */
  --z-sticky: 90;
  --z-menu: 99;
  --z-nav: 100;
  --z-hamburger: 101;

  /* Animation */
  --ease-out: cubic-bezier(0.4, 0.0, 0.2, 1);
  --duration-fast: 0.2s;
  --duration-normal: 0.25s;
  --duration-slow: 0.4s;

  font-size: 16px;
}

/* ============================================
   Reset & Base
   ============================================ */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

/* Prevent FOUC on hero landing page */
html:has(.page--hero-landing) {
  background: #fff;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text-primary);
  line-height: 1.6;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.page {
  width: 100%;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  overflow-x: hidden;
  background: linear-gradient(180deg, var(--warm-bg) 0%, #fbf6f2 100%);
}

a:focus-visible {
  outline: 1.5px solid var(--accent);
  outline-offset: 4px;
}

::selection {
  background: rgba(201, 104, 68, 0.12);
  color: var(--text-primary);
}

/* ============================================
   Navigation
   ============================================ */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2xl);
  padding: 1.25rem var(--page-padding);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--surface-nav);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: var(--z-nav);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.0625rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: #262626;
  text-decoration: none;
}

.nav__logo:hover {
  text-decoration: none;
}

.nav__logo-icon {
  flex-shrink: 0;
  display: block;
  opacity: 0.9;
}

.nav__logo-text {
  line-height: 1;
  text-decoration: none;
}

/* Desktop nav links — hidden on mobile by default (mobile-first) */
.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-2xl);
  margin-left: auto;
}

.nav__links--desktop {
  display: none;
}

.nav__links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.01em;
  transition: color var(--duration-fast) ease;
}

.nav__links a:hover {
  color: var(--text-primary);
}

/* Nav CTA Button — hidden on mobile by default */
.nav__cta-btn,
.nav__links .nav__cta-btn {
  display: none;
  align-items: center;
  padding: var(--space-sm) 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: #fff;
  background: var(--text-primary);
  border-radius: var(--radius-md);
  text-decoration: none;
  letter-spacing: 0.005em;
  transition: background-color var(--duration-fast) ease;
}

.nav__cta-btn:hover {
  background: var(--text-secondary);
}

/* Dropdown Menu */
.nav__dropdown {
  position: relative;
}

.nav__dropdown-trigger {
  background: none;
  border: none;
  font-family: inherit;
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.01em;
  transition: color var(--duration-fast) ease;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.nav__dropdown-trigger::after {
  content: '';
  width: 0;
  height: 0;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 4px solid currentColor;
  opacity: 0.6;
  transition: transform var(--duration-fast) ease;
}

.nav__dropdown:hover .nav__dropdown-trigger::after {
  transform: rotate(180deg);
}

.nav__dropdown-trigger:hover {
  color: var(--text-primary);
}

.nav__dropdown-menu {
  position: absolute;
  top: 100%;
  right: 0;
  margin-top: 0.75rem;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-sm) 0;
  min-width: 140px;
  box-shadow: var(--shadow-dropdown);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity var(--duration-fast) ease, transform var(--duration-fast) ease, visibility var(--duration-fast) ease;
}

.nav__dropdown:hover .nav__dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.nav__dropdown-menu a {
  display: block;
  padding: 0.625rem var(--space-md);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  transition: background-color 0.15s ease, color 0.15s ease;
}

.nav__dropdown-menu a:hover {
  background-color: rgba(0, 0, 0, 0.03);
  color: var(--text-primary);
}

/* Rich dropdown — matching app.metaphi.ai style */
.nav__dropdown-menu--rich {
  min-width: 240px;
  padding: 1.25rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-dropdown-rich);
}

.nav__dropdown-heading {
  font-size: 0.6875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  padding: 0 var(--space-sm);
  margin-bottom: var(--space-sm);
}

.nav__dropdown-menu a.nav__dropdown-item {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
  padding: 0.625rem var(--space-sm);
  border-radius: var(--radius-md);
}

.nav__dropdown-item-title {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-primary);
}

.nav__dropdown-item-desc {
  display: block;
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--text-tertiary);
}

.nav__dropdown-item:hover .nav__dropdown-item-title {
  color: var(--text-primary);
}

/* Products mega dropdown — two columns */
.nav__dropdown-menu.nav__dropdown-menu--products {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  width: 520px;
  min-width: 520px;
  padding: 1.75rem var(--space-xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-dropdown-rich);
}

.nav__dropdown-col {
  padding: 0 var(--space-lg);
}

.nav__dropdown-col:first-child {
  border-right: 1px solid var(--border);
  padding-left: 0;
}

.nav__dropdown-col:last-child {
  padding-right: 0;
}

/* ============================================
   Hamburger Menu Button
   Mobile-first: shown by default, hidden on desktop
   ============================================ */
.nav__hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  align-items: center;
  width: 44px;
  height: 44px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  z-index: var(--z-hamburger);
  -webkit-tap-highlight-color: transparent;
}

.nav__hamburger span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--duration-normal) var(--ease-out);
  transform-origin: center;
}

.nav__hamburger.active span:first-child {
  transform: translateY(3.5px) rotate(45deg);
}

.nav__hamburger.active span:last-child {
  transform: translateY(-3.5px) rotate(-45deg);
}

/* ============================================
   Mobile Menu Overlay
   ============================================ */
.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--surface-overlay);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: var(--z-menu);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity var(--duration-normal) var(--ease-out),
              visibility var(--duration-normal) var(--ease-out);
  overflow: hidden;
  touch-action: none;
  padding-top: 4.5rem;
}

.mobile-menu.active {
  opacity: 1;
  visibility: visible;
  pointer-events: all;
}

.mobile-menu__nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  text-align: center;
  padding: var(--space-xl);
}

/* Shared base for mobile menu links (both flat and sectioned layouts) */
.mobile-menu__nav > a,
.mobile-menu__section a {
  display: block;
  padding: var(--space-md) var(--space-xl);
  margin: 0 calc(var(--space-xl) * -1);
  font-size: 1.75rem;
  font-weight: 300;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.01em;
  border-radius: var(--radius-md);
  transition: color var(--duration-fast) ease,
              transform var(--duration-fast) ease,
              background-color var(--duration-fast) ease;
}

/* Entrance animation — only for flat layout links */
.mobile-menu__nav > a {
  opacity: 0;
  transform: translateY(20px);
  transition: color var(--duration-fast) ease,
              transform var(--duration-fast) ease,
              opacity var(--duration-slow) var(--ease-out),
              background-color var(--duration-fast) ease;
  position: relative;
}

/* Staggered animation timing */
.mobile-menu.active .mobile-menu__nav > a {
  opacity: 1;
  transform: translateY(0);
}

.mobile-menu.active .mobile-menu__nav > a:nth-child(1) { transition-delay: 0.05s; }
.mobile-menu.active .mobile-menu__nav > a:nth-child(2) { transition-delay: 0.1s; }
.mobile-menu.active .mobile-menu__nav > a:nth-child(3) { transition-delay: 0.15s; }
.mobile-menu.active .mobile-menu__nav > a:nth-child(4) { transition-delay: 0.2s; }
.mobile-menu.active .mobile-menu__nav > a:nth-child(5) { transition-delay: 0.25s; }
.mobile-menu.active .mobile-menu__nav > a:nth-child(6) { transition-delay: 0.3s; }

/* Active page indicator */
.mobile-menu__nav > a.active {
  color: var(--accent);
}

.mobile-menu__nav > a.active::before {
  content: '';
  position: absolute;
  left: 0;
  width: 4px;
  height: 60%;
  top: 20%;
  background: var(--accent);
  border-radius: 2px;
}

/* Hover/active state — shared */
.mobile-menu__nav > a:hover,
.mobile-menu__nav > a:active,
.mobile-menu__section a:hover,
.mobile-menu__section a:active {
  color: var(--accent);
  transform: translateX(4px);
  background-color: rgba(0, 0, 0, 0.02);
}

/* Descriptions under links — shared */
.mobile-menu__nav > a > small,
.mobile-menu__section a > small {
  display: block;
  font-size: 0.75rem;
  font-weight: 400;
  opacity: 0.6;
  margin-top: var(--space-xs);
  letter-spacing: 0;
}

/* Mobile Menu — Sectioned layout (PRODUCTS / PLATFORM) */
.mobile-menu__section {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.mobile-menu__heading {
  font-size: 0.6875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  padding: 0 var(--space-xl);
  margin-bottom: var(--space-xs);
}

/* Mobile Menu CTA button */
.mobile-menu__nav > a.mobile-menu__cta {
  display: block;
  text-align: center;
  padding: 0.875rem var(--space-xl);
  font-size: 1rem;
  font-weight: 500;
  color: #fff;
  background: var(--text-primary);
  border-radius: var(--radius-md);
  text-decoration: none;
  letter-spacing: 0.005em;
  margin-top: var(--space-md);
  transition: background-color var(--duration-fast) ease;
}

.mobile-menu__cta:hover {
  background: var(--text-secondary);
}

/* Stagger animation for sectioned mobile menu */
.mobile-menu__section,
.mobile-menu__cta {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}

.mobile-menu.active .mobile-menu__section:nth-child(1) {
  opacity: 1;
  transform: translateY(0);
  transition-delay: 0.05s;
}

.mobile-menu.active .mobile-menu__section:nth-child(2) {
  opacity: 1;
  transform: translateY(0);
  transition-delay: 0.15s;
}

.mobile-menu.active .mobile-menu__cta {
  opacity: 1;
  transform: translateY(0);
  transition-delay: 0.25s;
}

.mobile-menu__github {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-top: var(--space-md);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--border);
  font-size: 1rem;
  font-weight: 400;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}

.mobile-menu.active .mobile-menu__github {
  opacity: 1;
  transform: translateY(0);
  transition-delay: 0.3s;
}

.mobile-menu__github svg {
  width: 20px;
  height: 20px;
}

/* ============================================
   Hero (standard pages — 404, etc.)
   ============================================ */
.hero {
  flex: 1;
  display: flex;
  align-items: center;
  margin-top: var(--nav-height);
  min-height: calc(85vh - var(--nav-height));
  padding-top: max(12vh, 5rem);
  padding-bottom: max(2vh, 1rem);
}

.hero__content {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 var(--page-padding) var(--space-xl);
}

.hero__content h1 {
  font-size: clamp(2rem, 3.5vw, 2.75rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: clamp(2rem, 4vh, 2.5rem);
}

.hero__description {
  font-size: 1rem;
  line-height: 1.7;
  background: linear-gradient(180deg, var(--text-secondary) 0%, var(--text-tertiary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 400;
  margin-bottom: clamp(1.5rem, 3vh, 2rem);
  letter-spacing: 0.002em;
}

.hero__details {
  font-size: 1rem;
  line-height: 1.7;
  background: linear-gradient(180deg, var(--text-secondary) 0%, var(--text-tertiary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: clamp(1.25rem, 2.5vh, 1.75rem);
}

.hero__backing {
  font-size: 0.9375rem;
  color: var(--text-tertiary);
  margin-bottom: var(--space-2xl);
  letter-spacing: 0.01em;
}

.hero__backing strong {
  color: var(--text-secondary);
  font-weight: 500;
}

.hero__cta {
  display: inline-block;
  color: var(--accent);
  text-decoration: none;
  padding: 0;
  font-weight: 500;
  font-size: 0.9375rem;
  letter-spacing: 0.01em;
  border-bottom: 1.5px solid var(--accent);
  transition: opacity var(--duration-fast) ease;
  margin-top: clamp(1rem, 2vh, 1.5rem);
}

.hero__cta:hover {
  opacity: 0.7;
}

/* ============================================
   Research Section
   ============================================ */
.research {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 6rem var(--page-padding);
}

.research h2 {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-tertiary);
  margin-bottom: var(--space-2xl);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.research__grid {
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
}

.research__item {
  padding: 0;
}

.research__item h3 {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-sm);
  letter-spacing: -0.005em;
  display: inline;
}

.research__item p {
  font-size: 0.9375rem;
  background: linear-gradient(180deg, var(--text-secondary) 0%, var(--text-tertiary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.65;
  display: inline;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  padding: 3rem var(--page-padding);
  color: var(--text-tertiary);
  font-size: 0.875rem;
  text-align: center;
  letter-spacing: 0.01em;
}

.footer__links {
  margin-top: var(--space-sm);
}

.footer__links a {
  color: var(--text-tertiary);
  text-decoration: none;
}

.footer__links a:hover {
  color: var(--text-secondary);
  text-decoration: underline;
}

/* Footer — dark variant */
.footer--hero-landing {
  background: var(--surface-dark);
  color: rgba(255, 255, 255, 0.4);
}

.footer--hero-landing .footer__links a {
  color: rgba(255, 255, 255, 0.4);
}

.footer--hero-landing .footer__links a:hover {
  color: rgba(255, 255, 255, 0.7);
}

/* ============================================
   About Page
   ============================================ */
.about-page {
  padding: 8rem var(--page-padding) var(--space-3xl);
  max-width: var(--content-max-width);
  margin: 0 auto;
}

.about-page__content h1 {
  font-size: clamp(2.25rem, 4vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-3xl);
}

.founders {
  display: grid;
  gap: var(--space-3xl);
  margin-bottom: 5rem;
}

.founder__header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: 0.75rem;
}

.founder__info h2 {
  font-size: 1.375rem;
  font-weight: 500;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.founder__social {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  transition: color var(--duration-fast) ease;
  text-decoration: none;
}

.founder__social:hover {
  color: var(--text-secondary);
}

.founder__role {
  color: var(--text-tertiary);
  margin-bottom: var(--space-md);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.8125rem;
  font-weight: 500;
}

.founder__bio {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
}

.founder__contact {
  font-size: 0.9375rem;
  color: var(--text-tertiary);
}

/* ============================================
   Legal Pages (Privacy, Terms)
   ============================================ */
.legal-content {
  margin-top: calc(var(--space-xl) * -1);
}

.legal-content__date {
  color: var(--text-tertiary);
  font-size: 0.875rem;
  margin-bottom: var(--space-xl);
}

.legal-content h2 {
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
  letter-spacing: -0.01em;
}

.legal-content p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
}

.legal-content ul {
  padding-left: var(--space-lg);
  margin-bottom: var(--space-md);
}

.legal-content li {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
}

.legal-content a {
  color: var(--text-primary);
  text-decoration: underline;
}

.legal-content a:hover {
  color: var(--text-secondary);
}

/* ============================================
   Origin Story / Vision Sections
   ============================================ */
.origin-story,
.vision-section {
  margin-bottom: 3.5rem;
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.origin-story h2,
.vision-section h2 {
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 1.75rem;
  letter-spacing: -0.01em;
}

.origin-story p,
.vision-section p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
}

.origin-story__link {
  text-decoration: none;
  color: inherit;
}

.origin-story__title {
  cursor: pointer;
}

.origin-story__date {
  color: #666;
  font-size: 0.9rem;
  margin-bottom: var(--space-sm);
}

.origin-story__cta {
  display: inline-block;
  margin-top: var(--space-md);
}

.origin-story ul {
  padding-left: var(--space-lg);
  margin-bottom: var(--space-md);
}

.origin-story li {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
}

.origin-story a:not(.origin-story__link):not(.hero__cta) {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: var(--accent);
}

.origin-story a:not(.origin-story__link):not(.hero__cta):hover {
  opacity: 0.7;
}

/* ============================================
   Enterprise CTA & Partners Carousel
   ============================================ */
.enterprise-cta {
  margin-top: var(--space-2xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.partners {
  margin-top: 3.5rem;
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.partners h2 {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-tertiary);
  margin-bottom: var(--space-xl);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.partners__carousel {
  overflow: hidden;
  mask-image: linear-gradient(to right, transparent, black 10%, black 90%, transparent);
  -webkit-mask-image: linear-gradient(to right, transparent, black 10%, black 90%, transparent);
}

.partners__track {
  display: flex;
  gap: 3rem;
  width: max-content;
  animation: partners-scroll 25s linear infinite;
}

.partners__logo {
  flex-shrink: 0;
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--text-tertiary);
  letter-spacing: -0.01em;
  white-space: nowrap;
  padding: 0.75rem 0;
}

@keyframes partners-scroll {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

.partners__carousel:hover .partners__track {
  animation-play-state: paused;
}

/* ============================================
   Mobile Sticky Header for Essay Pages
   ============================================ */
.mobile-sticky-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 48px;
  background: var(--surface-nav);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
  z-index: var(--z-sticky);
  display: none;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-md);
  transform: translateY(-100%);
  transition: transform 0.3s var(--ease-out);
}

.mobile-sticky-header.visible {
  display: flex;
  transform: translateY(0);
}

.mobile-sticky-header__back {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  padding: var(--space-sm);
  margin-left: calc(var(--space-sm) * -1);
  border-radius: var(--radius-sm);
  transition: background-color var(--duration-fast) ease;
  flex-shrink: 0;
}

.mobile-sticky-header__back:hover,
.mobile-sticky-header__back:active {
  background-color: rgba(201, 104, 68, 0.08);
}

.mobile-sticky-header__back svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

.mobile-sticky-header__title {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--text-primary);
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 1;
  padding: 0 var(--space-md);
  opacity: 0.8;
}

.mobile-sticky-header__menu {
  background: none;
  border: none;
  padding: var(--space-sm);
  margin-right: calc(var(--space-sm) * -1);
  display: flex;
  flex-direction: column;
  gap: 3px;
  cursor: pointer;
  flex-shrink: 0;
}

.mobile-sticky-header__menu span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: all 0.3s var(--ease-out);
}

.mobile-sticky-header__menu.active span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.mobile-sticky-header__menu.active span:nth-child(2) {
  opacity: 0;
}

.mobile-sticky-header__menu.active span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* ============================================
   Essay Metadata
   ============================================ */
.essay-meta {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  margin: var(--space-lg) 0 var(--space-2xl) 0;
  padding: var(--space-md) 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  color: var(--text-secondary);
  flex-wrap: wrap;
}

.essay-meta__item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.essay-meta__item svg {
  width: 16px;
  height: 16px;
  opacity: 0.6;
  flex-shrink: 0;
}

.essay-meta__authors {
  display: flex;
  gap: var(--space-sm);
  align-items: center;
  flex-wrap: wrap;
}

.essay-meta__author {
  color: var(--text-primary);
  font-weight: 500;
  text-decoration: none;
  transition: color var(--duration-fast) ease;
}

.essay-meta__author:hover {
  color: var(--accent);
}

.essay-meta__date {
  color: var(--text-secondary);
}

.essay-meta__reading-time {
  color: var(--text-secondary);
}

/* ============================================
   Hero Landing — Full-screen image with overlay
   ============================================ */
.page--hero-landing {
  background: #fff;
  min-height: 0;
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
  overscroll-behavior: none;
  touch-action: manipulation;
}

.hero-landing {
  position: relative;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  overflow: hidden;
}

.hero-landing__grid {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}

.hero-landing__content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 0 var(--space-xl);
  padding-bottom: max(4.5rem, calc(3rem + env(safe-area-inset-bottom)));
  max-width: 800px;
}

.hero-landing__content h1 {
  font-size: clamp(2.75rem, 6vw, 5rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 1.1;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
}

.hero-landing__content p {
  font-size: clamp(0.9375rem, 1.5vw, 1.125rem);
  line-height: 1.6;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto var(--space-xl);
  font-weight: 300;
}

.hero-landing__ctas {
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
}

.hero-landing__cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.8125rem 1.75rem;
  font-size: 0.9375rem;
  font-weight: 500;
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: transform var(--duration-fast) ease, box-shadow var(--duration-fast) ease, background-color var(--duration-fast) ease, border-color var(--duration-fast) ease;
  letter-spacing: 0.005em;
}

.hero-landing__cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.hero-landing__cta svg {
  flex-shrink: 0;
  transition: transform var(--duration-fast) ease;
}

.hero-landing__cta:hover svg {
  transform: translateX(2px);
}

.hero-landing__cta--primary {
  background: var(--text-primary);
  color: #fff;
  border: 1px solid var(--text-primary);
}

.hero-landing__cta--primary:hover {
  background: var(--text-secondary);
  border-color: var(--text-secondary);
}

.hero-landing__cta--secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid rgba(0, 0, 0, 0.2);
}

.hero-landing__cta--secondary:hover {
  border-color: rgba(0, 0, 0, 0.4);
  background: rgba(0, 0, 0, 0.03);
}

/* Hero landing nav — transparent overlay on white */
.page--hero-landing .nav {
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  padding-top: max(1.25rem, env(safe-area-inset-top, 1.25rem));
  padding-left: max(4%, env(safe-area-inset-left, 4%));
  padding-right: max(4%, env(safe-area-inset-right, 4%));
}

/* Nav scroll behavior — frosted white when scrolled */
.page--hero-landing .nav--scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* Hero entrance — staggered fade-up */
.hero-landing__content h1,
.hero-landing__content p,
.hero-landing__ctas {
  opacity: 0;
  transform: translateY(20px);
  animation: heroFadeIn 0.8s cubic-bezier(0.0, 0.0, 0.2, 1) forwards;
}

.hero-landing__content h1   { animation-delay: 0.15s; }
.hero-landing__content p    { animation-delay: 0.3s; }
.hero-landing__ctas          { animation-delay: 0.45s; }

@keyframes heroFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================================
   Enterprise Page
   ============================================ */
.enterprise {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 8rem var(--page-padding) var(--space-3xl);
  max-width: var(--content-max-width);
  margin: 0 auto;
}

.enterprise__content h1 {
  font-size: clamp(2.25rem, 4vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-3xl);
}

.enterprise__content p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
}

.enterprise__content p:first-of-type {
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.enterprise__cta {
  display: inline-block;
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9375rem;
  letter-spacing: 0.01em;
  border-bottom: 1.5px solid var(--accent);
  transition: opacity var(--duration-fast) ease;
  margin-top: clamp(1rem, 2vh, 1.5rem);
}

.enterprise__cta:hover {
  opacity: 0.7;
}

.enterprise__partners {
  margin-top: 3.5rem;
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

/* ============================================
   Responsive — Desktop (min-width: 769px)
   Show desktop nav, hide hamburger
   ============================================ */
@media (min-width: 769px) {
  .nav__links--desktop {
    display: flex;
  }

  .nav__cta-btn,
  .nav__links .nav__cta-btn {
    display: inline-flex;
  }

  .nav__hamburger {
    display: none;
  }

  .mobile-sticky-header {
    display: none;
  }
}

/* ============================================
   Responsive — Tablet & Mobile (max-width: 768px)
   ============================================ */
@media (max-width: 768px) {
  .nav {
    padding: var(--space-md) 5%;
    position: fixed;
  }

  .nav__links {
    gap: var(--space-lg);
  }

  .nav__links a {
    font-size: 0.8125rem;
  }

  .hero {
    padding: 0 5%;
    margin-top: 3.5rem;
    min-height: auto;
    padding-top: clamp(4rem, 12vh, 6rem);
    padding-bottom: clamp(4rem, 12vh, 6rem);
  }

  .hero__content {
    padding: 0;
    max-width: none;
  }

  .hero__content h1 {
    font-size: clamp(1.5rem, 6vw, 2rem);
    line-height: 1.2;
    margin-bottom: clamp(1.5rem, 3.5vh, 2rem);
  }

  .hero__description,
  .hero__details {
    font-size: 0.9375rem;
    line-height: 1.65;
    margin-bottom: clamp(1rem, 2.5vh, 1.5rem);
  }

  .research {
    padding: var(--space-3xl) 5%;
    max-width: none;
  }

  .research__grid {
    max-width: none;
  }

  .footer {
    padding: var(--space-2xl) 5%;
  }

  .about-page {
    padding: 7rem 5% 3rem;
    max-width: 100%;
  }

  .origin-story p,
  .vision-section p {
    overflow-wrap: break-word;
  }

  .essay-meta {
    font-size: 0.85rem;
    gap: var(--space-md);
    padding: 0.75rem 0;
  }

  .essay-meta__item svg {
    width: 14px;
    height: 14px;
  }

  /* Hero landing responsive */
  .hero-landing__content {
    padding: 0 var(--space-lg);
    padding-bottom: max(3.5rem, calc(2rem + env(safe-area-inset-bottom, 0px)));
  }

  .hero-landing__content h1 {
    font-size: clamp(2rem, 8vw, 2.75rem);
    font-weight: 600;
    color: var(--text-primary);
  }

  .hero-landing__content p {
    font-size: 0.9375rem;
    margin-bottom: 1.75rem;
    color: var(--text-secondary);
  }

  .hero-landing__content p br {
    display: none;
  }

  .hero-landing__ctas {
    flex-direction: column;
    width: 100%;
  }

  .hero-landing__cta {
    width: 100%;
    justify-content: center;
    padding: 0.875rem var(--space-lg);
  }

  /* Enterprise mobile */
  .page--enterprise {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    min-height: 100dvh;
  }

  .enterprise {
    padding: 8rem 5% 3rem;
    max-width: 100%;
  }

  .enterprise__content h1 {
    font-size: 1.75rem;
    margin-bottom: var(--space-lg);
  }

  .enterprise__content p:first-of-type {
    padding-top: 1.25rem;
  }

  .enterprise__content p {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: 1.25rem;
  }

  .enterprise__cta {
    margin-top: var(--space-md);
  }

  .enterprise__partners {
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
  }

  .page--enterprise .mobile-menu__section a {
    font-size: 1.3rem;
  }
}

/* ============================================
   Responsive — Small phones (max-width: 380px)
   ============================================ */
@media (max-width: 380px) {
  .hero-landing__content {
    padding: 0 var(--space-md);
    padding-bottom: max(2.5rem, calc(1.5rem + env(safe-area-inset-bottom, 0px)));
  }

  .hero-landing__content h1 {
    font-size: 1.625rem;
  }

  .hero-landing__cta {
    font-size: 0.875rem;
    padding: 0.75rem 1.25rem;
  }
}

/* ============================================
   Accessibility — Reduced motion
   ============================================ */
@media (prefers-reduced-motion: reduce) {
  .hero-landing__content h1,
  .hero-landing__content p,
  .hero-landing__ctas {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .hero-landing__grid {
    animation: none;
  }
}