@font-face {
  font-family: 'CMU Serif';
  src: local('CMU Serif'),
    local('CMUSerif-Roman');
  /* Pure local lookup — will fall through to stack below if absent */
}

/* ------------------------------------------------------------------
   CSS CUSTOM PROPERTIES
------------------------------------------------------------------ */
:root {
  --bg-color: #fafafa;
  --text-color: #111111;
  --border-color: #111111;
  --gray-light: #e8e8e8;
  --gray-mid: #999999;
  --gray-dark: #444444;
  --border: 1px solid var(--border-color);
  --border-thin: 1px solid #d4d4d4;

  --font-serif: 'CMU Serif';
  --font-sans: 'Manjari', sans-serif;

  --nav-h: 64px;
  --max-w: 1120px;
  --radius: 0px;
  /* intentionally sharp/angular — academic look */
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

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

ul {
  list-style: none;
}

/* ------------------------------------------------------------------
   UTILITY
------------------------------------------------------------------ */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: 24px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ------------------------------------------------------------------
   COMPONENT: NAVBAR / HEADER
   Fixed at top, 1px bottom border, white bg, z-index above content
------------------------------------------------------------------ */
#site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  background-color: var(--bg-color);
  border-bottom: var(--border);
  display: flex;
  align-items: center;
}

#site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* Logo — CMU Serif, top-left */
.nav-logo {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 400;
  letter-spacing: 0.01em;
  color: var(--text-color);
  white-space: nowrap;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-logo span {
  /* Subtle emphasis on "Eureka" */
  font-style: italic;
}

.logo-img {
  height: 32px;
  width: auto;
  display: block;
}

/* Nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-color);
  position: relative;
  padding-bottom: 2px;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  text-decoration: underline;
}

/* Hamburger (mobile) */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 0;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 1px;
  background: var(--text-color);
}

/* Mobile nav open state */
.nav-open .nav-links {
  display: flex;
}

/* ------------------------------------------------------------------
   COMPONENT: HERO SECTION
   Full-viewport (minus nav), typographically dominant
------------------------------------------------------------------ */
#hero {
  margin-top: var(--nav-h);
  min-height: calc(100svh - var(--nav-h));
  border-bottom: var(--border);
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

/* Subtle grid texture — purely CSS, no images */
#hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--gray-light) 1px, transparent 1px),
    linear-gradient(90deg, var(--gray-light) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: 0.35;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding-block: 80px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

/* Hero Visual Layout (Right Column) */
.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.atom-container {
  width: 100%;
  max-width: 320px;
  aspect-ratio: 1;
  position: relative;
}

.atom-svg {
  width: 100%;
  height: 100%;
  overflow: visible;
}



.hero-eyebrow {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gray-dark);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero-eyebrow::before {
  content: '';
  display: block;
  width: 32px;
  height: 1px;
  background: var(--gray-dark);
  flex-shrink: 0;
}

.hero-headline {
  font-family: var(--font-serif);
  font-size: clamp(2.8rem, 7vw, 5.5rem);
  font-weight: 400;
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--text-color);
  margin-bottom: 28px;
  max-width: 820px;
}

.hero-headline em {
  font-style: italic;
}

.hero-sub {
  font-family: var(--font-sans);
  font-size: clamp(1rem, 2vw, 1.15rem);
  color: var(--gray-dark);
  max-width: 540px;
  margin-bottom: 44px;
  line-height: 1.8;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
}

/* Primary CTA — black solid, square edges */
.btn-primary {
  display: inline-block;
  padding: 14px 32px;
  background: var(--text-color);
  color: var(--bg-color);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: 1px solid var(--border-color);
  cursor: pointer;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--bg-color);
  color: var(--text-color);
}

/* Secondary CTA — outline */
.btn-secondary {
  display: inline-block;
  padding: 14px 32px;
  background: transparent;
  color: var(--text-color);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: 1px solid var(--border-color);
  cursor: pointer;
}

.btn-secondary:hover,
.btn-secondary:focus-visible {
  background: var(--text-color);
  color: var(--bg-color);
}

/* Running stat bar beneath headline */
.hero-stats {
  margin-top: 60px;
  padding-top: 32px;
  border-top: var(--border-thin);
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
}

.hero-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero-stat strong {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 400;
  line-height: 1;
}

.hero-stat span {
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--gray-mid);
}

/* ------------------------------------------------------------------
   SECTION HEADER (shared)
------------------------------------------------------------------ */
.section-label {
  font-family: var(--font-sans);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--gray-mid);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--gray-light);
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3.5vw, 2.5rem);
  font-weight: 400;
  line-height: 1.2;
  color: var(--text-color);
  margin-bottom: 12px;
}

.section-desc {
  font-size: 0.95rem;
  color: var(--gray-dark);
  max-width: 500px;
  line-height: 1.8;
  margin-bottom: 48px;
}

/* ------------------------------------------------------------------
   COMPONENT: CONTENT PILLARS / FEATURED SECTION
   3-column grid of bordered cards
------------------------------------------------------------------ */
#pillars {
  padding-block: 96px;
  border-bottom: var(--border);
}

.pillars-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  /* borders handle separation */
}

/* Card */
.pillar-card {
  border: var(--border);
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: relative;
  overflow: hidden;
}

/* Remove duplicate border between cards */
.pillar-card+.pillar-card {
  border-left: none;
}

.pillar-card:hover {
  background: #f3f3f3;
}

.pillar-number {
  font-family: var(--font-serif);
  font-size: 3.5rem;
  font-weight: 400;
  line-height: 1;
  color: var(--gray-light);
  pointer-events: none;
  user-select: none;
}

.pillar-card:hover .pillar-number {
  color: #d0d0d0;
}

.pillar-tag {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gray-mid);
  border: 1px solid var(--gray-light);
  display: inline-block;
  padding: 4px 10px;
  width: fit-content;
}

.pillar-placeholder {
  border: 1px dashed var(--border-color);
  padding: 16px;
  font-family: monospace;
  font-size: 0.7rem;
  white-space: pre;
  line-height: 1.25;
  text-align: center;
  color: var(--text-color);
  background-color: transparent;
  margin-block: 8px;
  user-select: none;
}

.pillar-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 400;
  line-height: 1.3;
  color: var(--text-color);
}

.pillar-desc {
  font-size: 0.875rem;
  color: var(--gray-dark);
  line-height: 1.75;
  flex: 1;
}

.pillar-link {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-color);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--text-color);
  width: fit-content;
}

.pillar-link:hover {
  gap: 14px;
}

.pillar-link::after {
  content: '→';
}

/* ------------------------------------------------------------------
   COMPONENT: LATEST ARTICLES (teaser strip)
------------------------------------------------------------------ */
#latest {
  padding-block: 96px;
  border-bottom: var(--border);
}

.articles-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.article-item {
  display: grid;
  grid-template-columns: 64px 1fr 280px 140px;
  align-items: center;
  gap: 24px;
  padding-block: 28px;
  border-bottom: var(--border-thin);
  cursor: pointer;
  padding-inline: 4px;
}

.article-item:first-child {
  border-top: var(--border-thin);
}

.article-item:hover {
  background: #f5f5f5;
}

.article-index {
  font-family: var(--font-serif);
  font-size: 0.8rem;
  color: var(--gray-mid);
  padding-top: 4px;
  text-align: right;
}

.article-label {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gray-mid);
  margin-bottom: 6px;
}

.article-title {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  font-weight: 400;
  line-height: 1.4;
  color: var(--text-color);
  margin-bottom: 6px;
}

.article-item:hover .article-title {
  text-decoration: underline;
}

.article-excerpt {
  font-size: 0.825rem;
  color: var(--gray-dark);
  line-height: 1.7;
}

.article-thumbnail {
  border: 1px dashed var(--border-color);
  padding: 10px 14px;
  font-family: monospace;
  font-size: 0.65rem;
  white-space: pre;
  line-height: 1.25;
  text-align: center;
  color: var(--text-color);
  align-self: center;
  background-color: transparent;
  user-select: none;
}

.article-meta {
  font-size: 0.7rem;
  color: var(--gray-mid);
  white-space: nowrap;
  text-align: right;
}

/* ------------------------------------------------------------------
   COMPONENT: CALL-TO-ACTION SECTION
   Minimal dark banner, social / channel links
------------------------------------------------------------------ */
#cta-section {
  padding-block: 96px;
  border-bottom: var(--border);
  background: var(--text-color);
  color: var(--bg-color);
}

#cta-section .section-title {
  color: var(--bg-color);
}

#cta-section .section-desc {
  color: #aaaaaa;
  margin-bottom: 40px;
}

.cta-channels {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 56px;
}

/* Channel pill button */
.btn-channel {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 24px;
  border: 1px solid #444444;
  color: var(--bg-color);
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
}

.btn-channel:hover,
.btn-channel:focus-visible {
  border-color: var(--bg-color);
  background: rgba(255, 255, 255, 0.06);
}

.btn-channel svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
  flex-shrink: 0;
}

/* Divider rule within dark section */
.cta-rule {
  border: none;
  border-top: 1px solid #333333;
  margin-block: 56px;
}

.cta-docs-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.cta-docs-text {
  max-width: 480px;
}

.cta-docs-text h3 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--bg-color);
  margin-bottom: 8px;
}

.cta-docs-text p {
  font-size: 0.875rem;
  color: #aaaaaa;
  line-height: 1.75;
}

/* Inverted primary button for dark bg */
.btn-primary-inv {
  display: inline-block;
  padding: 14px 32px;
  background: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: 1px solid var(--bg-color);
  cursor: pointer;
  white-space: nowrap;
}

.btn-primary-inv:hover,
.btn-primary-inv:focus-visible {
  background: transparent;
  color: var(--bg-color);
}

/* ------------------------------------------------------------------
   COMPONENT: FOOTER
   Minimal, monochrome, standard links
------------------------------------------------------------------ */
#site-footer {
  padding-block: 40px;
  border-top: var(--border);
}

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

.footer-logo {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  color: var(--text-color);
}

.footer-copy {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  color: var(--gray-mid);
}

.footer-links {
  display: flex;
  gap: 24px;
}

.footer-links a {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gray-dark);
}

.footer-links a:hover {
  color: var(--text-color);
  text-decoration: underline;
}

/* ------------------------------------------------------------------
   PAGE LOAD ANIMATION
   Staggered fade-up for key sections
------------------------------------------------------------------ */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }

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

.hero-eyebrow {
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.05s;
}

.hero-headline {
  animation: fadeUp 0.7s ease both;
  animation-delay: 0.15s;
}

.hero-sub {
  animation: fadeUp 0.7s ease both;
  animation-delay: 0.25s;
}

.hero-cta-group {
  animation: fadeUp 0.7s ease both;
  animation-delay: 0.35s;
}

.hero-stats {
  animation: fadeUp 0.7s ease both;
  animation-delay: 0.45s;
}

/* ------------------------------------------------------------------
   RESPONSIVE — TABLET (≤ 900px)
------------------------------------------------------------------ */
@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-visual {
    order: 2;
    max-width: 250px;
    margin-inline: auto;
    opacity: 0.85;
  }

  .pillars-grid {
    grid-template-columns: 1fr;
  }

  .pillar-card+.pillar-card {
    border-left: var(--border);
    border-top: none;
  }

  .article-item {
    grid-template-columns: 40px 1fr;
    gap: 16px 12px;
  }

  .article-meta {
    display: none;
  }

  .article-placeholder {
    grid-column: 2;
    max-width: 320px;
    margin-bottom: 12px;
    align-self: flex-start;
  }
}

/* ------------------------------------------------------------------
   RESPONSIVE — MOBILE (≤ 600px)
------------------------------------------------------------------ */
@media (max-width: 600px) {
  :root {
    --nav-h: 56px;
  }

  .logo-img {
    height: 28px;
  }

  /* Hamburger visible, nav links hidden by default */
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--bg-color);
    border-bottom: var(--border);
    flex-direction: column;
    align-items: flex-start;
    padding: 24px;
    gap: 24px;
    z-index: 99;
  }

  .nav-links a {
    font-size: 1rem;
  }

  /* Open state toggled via JS */
  body.nav-open .nav-links {
    display: flex;
  }

  .hero-inner {
    padding-block: 56px;
  }

  .hero-stats {
    gap: 24px;
  }

  #pillars {
    padding-block: 64px;
  }

  .pillar-card {
    padding: 28px 20px;
  }

  #latest {
    padding-block: 64px;
  }

  .article-item {
    grid-template-columns: 32px 1fr;
    gap: 12px;
  }

  .article-placeholder {
    grid-column: 2;
    max-width: 100%;
    margin-bottom: 8px;
  }

  #cta-section {
    padding-block: 64px;
  }

  .cta-docs-row {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* ------------------------------------------------------------------
   ARTICLE CONTENT STYLING
------------------------------------------------------------------ */
body.doc-content {
  max-width: none;
  padding: 0;
}

.article-content {
  max-width: 1000px;
  margin: 0 auto;
  padding: 120px 32px 80px 32px;
}

.article-content p,
.article-content li {
  text-align: justify;
}