:root {
  /* Cognitive Blueprint System Palette */
  --cognitive-navy: #101B2D;
  --blueprint-white: #F7F8F5;
  --ai-blue: #386FA4;
  --knowledge-teal: #3C9180;
  --signal-gold: #D2A85A;
  --soft-grid: #DCE3E1;
  --deep-text: #17202A;
  --muted-grey: #66736F;
  --accent-orange: #C87545;

  /* Typography */
  --font-display: 'Inter', system-ui, -apple-system, sans-serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  
  /* Spacing & Layout */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  --container-width: 1200px;
  
  /* Utilities */
  --border-radius: 4px;
  --transition: all 0.3s ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-body);
  color: var(--deep-text);
  background-color: var(--blueprint-white);
  line-height: 1.6;
  font-size: 16px;
  overflow-x: hidden;
  background-image: 
    linear-gradient(var(--soft-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--soft-grid) 1px, transparent 1px);
  background-size: 40px 40px;
  background-attachment: fixed;
}

/* Accessibility Focus */
*:focus-visible {
  outline: 3px solid var(--accent-orange);
  outline-offset: 2px;
}

/* Typography */
h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.2;
  color: var(--cognitive-navy);
  margin-bottom: var(--spacing-sm);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: clamp(1.5rem, 3vw, 2rem); }
h4 { font-size: 1.25rem; }

p { margin-bottom: var(--spacing-sm); }
a { color: var(--ai-blue); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--cognitive-navy); text-decoration: underline; }

.tech-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 700;
  color: var(--knowledge-teal);
  display: block;
  margin-bottom: var(--spacing-xs);
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

section {
  padding: var(--spacing-xl) 0;
  position: relative;
  background: rgba(247, 248, 245, 0.95);
}

section.alternate {
  background-color: var(--cognitive-navy);
  color: var(--blueprint-white);
}

section.alternate h2, 
section.alternate h3, 
section.alternate p {
  color: var(--blueprint-white);
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid var(--soft-grid);
  box-shadow: 0 4px 20px rgba(16, 27, 45, 0.05);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.brand-logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--cognitive-navy);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-logo::before {
  content: '';
  display: block;
  width: 24px;
  height: 24px;
  background-color: var(--ai-blue);
  border: 2px solid var(--cognitive-navy);
  border-radius: 2px;
}

.brand-logo:hover {
  text-decoration: none;
}

.main-nav ul {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  align-items: center;
}

.main-nav a {
  color: var(--deep-text);
  font-weight: 500;
  font-size: 0.95rem;
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--ai-blue);
  text-decoration: none;
}

.btn-primary {
  background-color: var(--cognitive-navy);
  color: var(--blueprint-white) !important;
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  border: 1px solid var(--cognitive-navy);
  display: inline-block;
  text-align: center;
  cursor: pointer;
}

.btn-primary:hover {
  background-color: var(--ai-blue);
  border-color: var(--ai-blue);
  text-decoration: none;
}

.btn-secondary {
  background-color: transparent;
  color: var(--cognitive-navy) !important;
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  border: 2px solid var(--cognitive-navy);
  display: inline-block;
  text-align: center;
  cursor: pointer;
}

.btn-secondary:hover {
  background-color: var(--cognitive-navy);
  color: var(--blueprint-white) !important;
  text-decoration: none;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 1001;
}

.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--cognitive-navy);
  margin: 5px 0;
  transition: var(--transition);
}

/* Hero Section */
.hero {
  padding: var(--spacing-xl) 0;
  border-bottom: 1px solid var(--soft-grid);
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  align-items: center;
}

.hero-content {
  max-width: 600px;
}

.hero-visual {
  position: relative;
  height: 400px;
  border: 1px solid var(--soft-grid);
  background-color: white;
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 10px 10px 0 var(--soft-grid);
}

.hero-visual img {
  max-width: 100%;
  height: auto;
}

/* Components */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.blueprint-card {
  background: white;
  border: 1px solid var(--soft-grid);
  padding: var(--spacing-md);
  border-radius: var(--border-radius);
  transition: var(--transition);
  position: relative;
}

.blueprint-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background-color: var(--knowledge-teal);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 0.3s ease;
}

.blueprint-card:hover {
  box-shadow: 0 10px 30px rgba(16, 27, 45, 0.05);
  transform: translateY(-5px);
}

.blueprint-card:hover::before {
  transform: scaleY(1);
}

/* AI Adoption Framework */
.framework-timeline {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
  position: relative;
}

.framework-timeline::before {
  content: '';
  position: absolute;
  left: 24px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--soft-grid);
}

.framework-step {
  display: flex;
  gap: var(--spacing-md);
  position: relative;
  z-index: 1;
}

.step-number {
  width: 50px;
  height: 50px;
  background: var(--cognitive-navy);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-family: var(--font-display);
  flex-shrink: 0;
  border: 4px solid var(--blueprint-white);
}

.step-content {
  background: white;
  padding: var(--spacing-md);
  border: 1px solid var(--soft-grid);
  border-radius: var(--border-radius);
  flex-grow: 1;
}

/* Challenge Selector */
.challenge-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.challenge-tab {
  padding: 1rem 1.5rem;
  background: white;
  border: 1px solid var(--soft-grid);
  cursor: pointer;
  font-weight: 600;
  border-radius: var(--border-radius);
  transition: var(--transition);
}

.challenge-tab[aria-selected="true"] {
  background: var(--cognitive-navy);
  color: white;
  border-color: var(--cognitive-navy);
}

.challenge-panel {
  display: none;
  background: white;
  padding: var(--spacing-md);
  border: 1px solid var(--soft-grid);
  border-left: 4px solid var(--ai-blue);
  border-radius: var(--border-radius);
}

.challenge-panel.active {
  display: block;
  animation: fadeIn 0.4s ease forwards;
}

/* Forms */
.form-group {
  margin-bottom: var(--spacing-sm);
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--cognitive-navy);
}

.form-control {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--muted-grey);
  border-radius: var(--border-radius);
  font-family: var(--font-body);
  font-size: 1rem;
}

.form-control:focus {
  outline: none;
  border-color: var(--ai-blue);
  box-shadow: 0 0 0 3px rgba(56, 111, 164, 0.2);
}

textarea.form-control {
  min-height: 150px;
  resize: vertical;
}

.form-message {
  padding: 1rem;
  margin-top: 1rem;
  border-radius: var(--border-radius);
  display: none;
}

.form-message.success {
  background: rgba(60, 145, 128, 0.1);
  color: var(--knowledge-teal);
  border: 1px solid var(--knowledge-teal);
  display: block;
}

/* Footer */
.site-footer {
  background-color: var(--cognitive-navy);
  color: var(--soft-grid);
  padding: var(--spacing-lg) 0 var(--spacing-md);
  border-top: 4px solid var(--signal-gold);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

.footer-col h4 {
  color: white;
  margin-bottom: var(--spacing-sm);
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 0.5rem;
}

.footer-col a {
  color: var(--soft-grid);
}

.footer-col a:hover {
  color: var(--signal-gold);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
}

/* Cookie Banner */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background: white;
  border-top: 1px solid var(--soft-grid);
  box-shadow: 0 -4px 20px rgba(0,0,0,0.1);
  padding: var(--spacing-md);
  z-index: 9999;
  transform: translateY(100%);
  transition: transform 0.5s ease;
}

.cookie-banner.show {
  transform: translateY(0);
}

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

.cookie-text {
  flex: 1;
  min-width: 300px;
  font-size: 0.9rem;
}

.cookie-actions {
  display: flex;
  gap: 0.5rem;
}

.cookie-actions button {
  font-size: 0.85rem;
  padding: 0.5rem 1rem;
}

/* Knowledge Hub specific */
.article-meta {
  font-size: 0.85rem;
  color: var(--muted-grey);
  margin-bottom: 0.5rem;
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s ease;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

/* Responsive Breakpoints */
@media (max-width: 1200px) {
  /* Default container handles this */
}

@media (max-width: 768px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .main-nav {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background: white;
    padding: var(--spacing-lg) var(--spacing-sm);
    transition: var(--transition);
    overflow-y: auto;
  }
  
  .main-nav.active {
    left: 0;
  }
  
  .main-nav ul {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-sm);
  }
  
  .main-nav .btn-primary {
    margin-top: var(--spacing-sm);
    width: 100%;
  }

  .framework-timeline::before {
    left: 20px;
  }

  .step-number {
    width: 40px;
    height: 40px;
    font-size: 1rem;
  }
}

@media (max-width: 480px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  
  .card-grid {
    grid-template-columns: 1fr;
  }

  .cookie-actions {
    flex-direction: column;
    width: 100%;
  }
  
  .cookie-actions button {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, ::before, ::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}