:root {
  /* Color Palette */
  --nav-dark: #0D1B2A;
  --intel-white: #F8F9F6;
  --ai-blue: #3478B5;
  --knowledge-teal: #2F8F83;
  --signal-gold: #D6AD5C;
  --soft-grid: #DCE4E1;
  --deep-graphite: #1C252C;
  --muted-text: #68736F;
  --accent-copper: #C46B45;

  /* Typography */
  --font-display: 'Inter', system-ui, -apple-system, sans-serif; /* Premium sans */
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;

  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 8rem;

  /* UI */
  --radius: 4px; /* Structured, not too rounded */
  --border-subtle: 1px solid var(--soft-grid);
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(13, 27, 42, 0.08);
  
  /* Transitions */
  --transition: all 0.3s ease;
}

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

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

body {
  font-family: var(--font-body);
  color: var(--deep-graphite);
  background-color: var(--intel-white);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.2;
  color: var(--nav-dark);
  margin-bottom: var(--space-sm);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(2rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.5rem, 3vw, 1.75rem); }

p { margin-bottom: var(--space-md); }
a { color: var(--ai-blue); text-decoration: none; transition: var(--transition); }
a:hover, a:focus { color: var(--accent-copper); }

.tech-label {
  display: inline-block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 700;
  color: var(--knowledge-teal);
  margin-bottom: var(--space-xs);
}

/* Layout */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section {
  padding: var(--space-xl) 0;
}

.section-light { background-color: var(--intel-white); }
.section-dark { background-color: var(--nav-dark); color: var(--intel-white); }
.section-dark h2, .section-dark h3 { color: var(--intel-white); }
.section-dark p { color: var(--soft-grid); }

/* Navigation Architecture Grid Pattern */
.bg-grid {
  background-image: 
    linear-gradient(var(--soft-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--soft-grid) 1px, transparent 1px);
  background-size: 40px 40px;
  background-position: center top;
}

.bg-grid-dark {
  background-image: 
    linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
  background-size: 40px 40px;
  background-color: var(--nav-dark);
}

/* Accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--accent-copper);
  color: white;
  padding: 8px;
  z-index: 10000;
  transition: top 0.2s;
}
.skip-link:focus { top: 0; }

:focus-visible {
  outline: 2px solid var(--accent-copper);
  outline-offset: 2px;
}

@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;
  }
}

/* Header & Nav */
.site-header {
  position: sticky;
  top: 0;
  background-color: var(--nav-dark);
  color: var(--intel-white);
  z-index: 1000;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

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

.logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--intel-white);
  letter-spacing: -0.02em;
}
.logo:hover { color: var(--signal-gold); }

.desktop-nav { display: none; }

.desktop-nav ul {
  display: flex;
  list-style: none;
  gap: var(--space-md);
  align-items: center;
}

.desktop-nav a {
  color: var(--intel-white);
  font-size: 0.9rem;
  font-weight: 500;
}
.desktop-nav a:hover { color: var(--signal-gold); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  border: 2px solid transparent;
  font-size: 0.95rem;
}

.btn-primary {
  background-color: var(--ai-blue);
  color: #fff;
}
.btn-primary:hover {
  background-color: #2a6192;
  color: #fff;
}

.btn-secondary {
  background-color: transparent;
  border-color: var(--ai-blue);
  color: var(--ai-blue);
}
.btn-secondary:hover {
  background-color: var(--ai-blue);
  color: #fff;
}

.btn-accent {
  background-color: var(--accent-copper);
  color: #fff;
}
.btn-accent:hover {
  background-color: #a35635;
  color: #fff;
}

/* Mobile Menu Button */
.mobile-menu-btn {
  background: none;
  border: none;
  color: var(--intel-white);
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 0.5rem;
}
.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: currentColor;
  transition: var(--transition);
}

/* Fullscreen Mobile Menu */
.mobile-menu {
  position: fixed;
  top: 80px;
  left: 0;
  width: 100%;
  height: calc(100vh - 80px);
  background-color: var(--nav-dark);
  padding: var(--space-md);
  transform: translateX(100%);
  transition: transform 0.3s ease-in-out;
  overflow-y: auto;
  z-index: 999;
}
.mobile-menu.is-open { transform: translateX(0); }
.mobile-menu ul { list-style: none; display: flex; flex-direction: column; gap: var(--space-sm); }
.mobile-menu a { display: block; padding: 1rem 0; font-size: 1.2rem; color: var(--intel-white); border-bottom: 1px solid rgba(255,255,255,0.05); }
.mobile-menu a:hover { color: var(--signal-gold); }

@media (min-width: 1200px) {
  .mobile-menu-btn { display: none; }
  .desktop-nav { display: block; }
}

/* Hero Section */
.hero {
  position: relative;
  padding: calc(var(--space-xl) * 1.5) 0 var(--space-xl);
  border-bottom: var(--border-subtle);
  overflow: hidden;
}
.hero-content {
  max-width: 800px;
  position: relative;
  z-index: 2;
}
.hero p.lead {
  font-size: 1.25rem;
  color: var(--muted-text);
  max-width: 600px;
}

/* Pathway Graphic (CSS) */
.hero-graphic {
  position: absolute;
  right: -5%;
  top: 20%;
  width: 50%;
  height: 60%;
  opacity: 0.1;
  z-index: 1;
  pointer-events: none;
  border-left: 2px dashed var(--nav-dark);
  border-bottom: 2px dashed var(--nav-dark);
}
.hero-graphic::before {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  background: var(--ai-blue);
  border-radius: 50%;
  bottom: -11px;
  left: 40%;
}
.hero-graphic::after {
  content: '';
  position: absolute;
  width: 10px;
  height: 10px;
  background: var(--accent-copper);
  top: 20%;
  left: -6px;
}

/* Grid Layouts */
.grid-2 { display: grid; gap: var(--space-md); }
.grid-3 { display: grid; gap: var(--space-md); }
.grid-4 { display: grid; gap: var(--space-md); }

@media (min-width: 768px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1200px) {
  .grid-4 { grid-template-columns: repeat(4, 1fr); }
}

/* Cards (Architecture Blocks) */
.arch-block {
  background: #fff;
  border: var(--border-subtle);
  padding: var(--space-md);
  border-radius: var(--radius);
  transition: var(--transition);
  position: relative;
  display: flex;
  flex-direction: column;
}
.arch-block:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--ai-blue);
}
.arch-block h3 { font-size: 1.25rem; }
.arch-block p { color: var(--muted-text); font-size: 0.95rem; flex-grow: 1; }
.block-link {
  margin-top: auto;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}
.block-link::after { content: '→'; transition: transform 0.2s; }
.block-link:hover::after { transform: translateX(4px); }

/* Process Framework */
.framework-steps {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  position: relative;
}
@media (min-width: 768px) {
  .framework-steps {
    flex-direction: row;
    gap: 0;
  }
}
.step {
  flex: 1;
  position: relative;
  padding: var(--space-md);
  border-left: 2px solid var(--soft-grid);
}
@media (min-width: 768px) {
  .step {
    border-left: none;
    border-top: 2px solid var(--soft-grid);
    padding-top: var(--space-md);
    padding-left: 0;
    padding-right: var(--space-md);
  }
}
.step-num {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--soft-grid);
  position: absolute;
  top: 10px;
  left: -20px;
  background: var(--intel-white);
  padding: 0 10px;
}
@media (min-width: 768px) {
  .step-num {
    top: -24px;
    left: 0;
  }
}
.step:hover .step-num { color: var(--ai-blue); }

/* Page Header */
.page-header {
  padding: var(--space-xl) 0 var(--space-md);
  border-bottom: var(--border-subtle);
}
.page-header h1 { margin-bottom: var(--space-xs); }
.page-header p.lead { font-size: 1.2rem; color: var(--muted-text); max-width: 800px; }

/* Content Sections */
.content-layout {
  display: grid;
  gap: var(--space-lg);
  padding: var(--space-xl) 0;
}
@media (min-width: 768px) {
  .content-layout { grid-template-columns: 2fr 1fr; }
}
.main-col h2 { margin-top: var(--space-lg); padding-top: var(--space-md); border-top: 1px dashed var(--soft-grid); }
.main-col h2:first-child { margin-top: 0; padding-top: 0; border-top: none; }
.main-col ul { margin-bottom: var(--space-md); padding-left: var(--space-md); color: var(--muted-text); }
.main-col li { margin-bottom: 0.5rem; }

/* Sidebar */
.sidebar-box {
  background: var(--intel-white);
  border: var(--border-subtle);
  padding: var(--space-md);
  border-radius: var(--radius);
  margin-bottom: var(--space-md);
}
.sidebar-box h3 { font-size: 1.1rem; border-bottom: 2px solid var(--nav-dark); padding-bottom: 0.5rem; margin-bottom: 1rem; }

/* Forms */
.form-group { margin-bottom: var(--space-md); }
label { display: block; font-weight: 600; margin-bottom: 0.5rem; color: var(--nav-dark); font-size: 0.9rem; }
input[type="text"], input[type="email"], select, textarea {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--soft-grid);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 1rem;
  background: #fff;
  transition: border-color 0.2s;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--ai-blue);
  box-shadow: 0 0 0 3px rgba(52, 120, 181, 0.1);
}
textarea { resize: vertical; min-height: 150px; }
.form-message { display: none; padding: 1rem; background: #e6f4ea; border-left: 4px solid #34a853; margin-top: 1rem; }

/* Footer */
.site-footer {
  background-color: var(--deep-graphite);
  color: var(--soft-grid);
  padding: var(--space-lg) 0 var(--space-md);
  font-size: 0.9rem;
}
.footer-grid {
  display: grid;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}
@media (min-width: 768px) {
  .footer-grid { grid-template-columns: repeat(4, 1fr); }
}
.footer-col h4 { color: var(--intel-white); margin-bottom: 1rem; font-size: 1rem; }
.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 {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: var(--space-md);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  justify-content: space-between;
}
@media (min-width: 768px) {
  .footer-bottom { flex-direction: row; }
}
.footer-disclaimer { font-size: 0.8rem; color: #888; max-width: 600px; }

/* Cookie Banner */
#cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background: #fff;
  border-top: var(--border-subtle);
  box-shadow: 0 -4px 12px rgba(0,0,0,0.05);
  padding: var(--space-md);
  z-index: 10000;
  transform: translateY(100%);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
#cookie-banner.is-visible { transform: translateY(0); }
.cookie-content p { margin-bottom: 0; font-size: 0.9rem; }
.cookie-actions { display: flex; gap: 0.5rem; flex-wrap: wrap; }
@media (min-width: 768px) {
  #cookie-banner { flex-direction: row; align-items: center; justify-content: space-between; }
  .cookie-content { max-width: 60%; }
}

/* Reveal Animation */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity 0.6s ease-out, transform 0.6s ease-out; }
.reveal.active { opacity: 1; transform: translateY(0); }

/* Table */
table { width: 100%; border-collapse: collapse; margin-bottom: var(--space-md); }
th, td { padding: 0.75rem; border: var(--border-subtle); text-align: left; }
th { background: var(--soft-grid); font-weight: 600; color: var(--nav-dark); }