/* ===== BI Consult AI — Design System ===== */

/* --- CSS Variables --- */
:root {
  --primary: #2B5EA7;
  --primary-dark: #1A3D6E;
  --primary-light: #3B82F6;
  --accent: #3B82F6;
  --bg-white: #FFFFFF;
  --bg-light: #F5F7FA;
  --bg-dark: #1A3D6E;
  --text-main: #1E293B;
  --text-secondary: #64748B;
  --text-white: #FFFFFF;
  --border: #E2E8F0;
  --shadow: 0 1px 3px rgba(0,0,0,.1), 0 1px 2px rgba(0,0,0,.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,.1), 0 2px 4px rgba(0,0,0,.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,.1), 0 4px 6px rgba(0,0,0,.05);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: .2s ease;
  --max-width: 1200px;
  --header-h: 72px;
}

/* --- Reset --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--text-main);
  background: var(--bg-white);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-dark); }
ul, ol { list-style: none; }

/* --- Typography --- */
h1, h2, h3, h4, h5 { line-height: 1.25; color: var(--text-main); font-weight: 700; }
h1 { font-size: clamp(2rem, 4vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); margin-bottom: .75rem; }
h3 { font-size: clamp(1.2rem, 2vw, 1.5rem); margin-bottom: .5rem; }
h4 { font-size: 1.125rem; margin-bottom: .5rem; }
p { margin-bottom: 1rem; }

/* --- Container --- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.5rem; }

/* --- Header --- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  height: var(--header-h);
}
.header-inner {
  max-width: var(--max-width); margin: 0 auto; padding: 0 1.5rem;
  display: flex; align-items: center; justify-content: space-between;
  height: 100%;
}
.header-logo img { height: 44px; width: auto; }
.header-logo { display: flex; align-items: center; gap: .5rem; text-decoration: none; }

/* --- Desktop Nav --- */
.main-nav { display: flex; align-items: center; gap: 0; }
.main-nav > li { position: relative; }
.main-nav > li > a {
  display: block; padding: .5rem .75rem;
  font-size: .875rem; font-weight: 500; color: var(--text-main);
  transition: color var(--transition);
  white-space: nowrap;
}
.main-nav > li > a:hover,
.main-nav > li.active > a { color: var(--accent); }

/* Dropdown */
.dropdown-menu {
  display: none; position: absolute; top: 100%; left: 0;
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow-lg);
  min-width: 260px; padding: .5rem 0; z-index: 110;
}
.main-nav > li:hover .dropdown-menu,
.main-nav > li.open .dropdown-menu { display: block; }
.dropdown-menu a {
  display: block; padding: .5rem 1rem; font-size: .85rem;
  color: var(--text-main); transition: background var(--transition);
}
.dropdown-menu a:hover { background: var(--bg-light); color: var(--accent); }
.dropdown-menu .badge-soon {
  display: inline-block; font-size: .65rem; background: var(--bg-light);
  color: var(--text-secondary); padding: .1rem .4rem; border-radius: 4px;
  margin-left: .5rem; vertical-align: middle;
}

/* Header CTA */
.header-cta {
  display: inline-flex; align-items: center;
  background: var(--accent); color: var(--text-white);
  padding: .5rem 1.25rem; border-radius: var(--radius);
  font-size: .875rem; font-weight: 600;
  transition: background var(--transition);
  white-space: nowrap;
}
.header-cta:hover { background: var(--primary); color: var(--text-white); }

/* Hamburger */
.hamburger {
  display: none; background: none; border: none; cursor: pointer;
  width: 32px; height: 32px; position: relative;
  flex-direction: column; justify-content: center; align-items: center; gap: 5px;
}
.hamburger span {
  display: block; width: 24px; height: 2px; background: var(--text-main);
  transition: var(--transition);
}

/* --- Mobile Nav --- */
.mobile-nav {
  display: none; position: fixed; top: var(--header-h); left: 0; right: 0; bottom: 0;
  background: var(--bg-white); overflow-y: auto; z-index: 99; padding: 1rem;
}
.mobile-nav.open { display: block; }
.mobile-nav > li { border-bottom: 1px solid var(--border); }
.mobile-nav > li > a {
  display: flex; justify-content: space-between; align-items: center;
  padding: .875rem 0; font-weight: 600; color: var(--text-main); font-size: 1rem;
}
.mobile-nav .mobile-sub { display: none; padding: 0 0 .75rem 1rem; }
.mobile-nav > li.open .mobile-sub { display: block; }
.mobile-nav .mobile-sub a {
  display: block; padding: .4rem 0; font-size: .9rem; color: var(--text-secondary);
}
.mobile-nav .mobile-cta {
  display: block; text-align: center; margin-top: 1rem;
  background: var(--accent); color: var(--text-white);
  padding: .875rem; border-radius: var(--radius); font-weight: 600;
}

/* --- Hero --- */
.hero {
  padding: 4rem 0; background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: var(--text-white);
}
.hero h1 { color: var(--text-white); margin-bottom: 1rem; }
.hero p { color: rgba(255,255,255,.85); font-size: 1.125rem; max-width: 700px; }
.hero .btn-primary { margin-top: 1.5rem; }
.hero-content { max-width: 700px; }

.hero-home {
  padding: 5rem 0;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 60%, #4A90D9 100%);
}
.hero-home h1 { font-size: clamp(2.2rem, 4.5vw, 3.25rem); margin-bottom: 1.25rem; }
.hero-home p { font-size: 1.2rem; }

/* --- Buttons --- */
.btn-primary {
  display: inline-flex; align-items: center; gap: .5rem;
  background: var(--accent); color: var(--text-white);
  padding: .75rem 1.75rem; border-radius: var(--radius);
  font-weight: 600; font-size: 1rem;
  transition: background var(--transition), transform var(--transition);
  border: none; cursor: pointer;
}
.btn-primary:hover { background: #2563EB; color: var(--text-white); transform: translateY(-1px); }
.btn-outline {
  display: inline-flex; align-items: center; gap: .5rem;
  background: transparent; color: var(--accent);
  padding: .75rem 1.75rem; border-radius: var(--radius);
  font-weight: 600; font-size: 1rem;
  border: 2px solid var(--accent);
  transition: background var(--transition);
  cursor: pointer;
}
.btn-outline:hover { background: var(--accent); color: var(--text-white); }
.btn-white {
  display: inline-flex; align-items: center; gap: .5rem;
  background: var(--bg-white); color: var(--primary);
  padding: .75rem 1.75rem; border-radius: var(--radius);
  font-weight: 600; font-size: 1rem; border: none; cursor: pointer;
  transition: background var(--transition), transform var(--transition);
}
.btn-white:hover { background: #E8EDFB; transform: translateY(-1px); }

/* --- Stats Row --- */
.stats-row {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem; padding: 3rem 0;
}
.stat-item { text-align: center; }
.stat-number { font-size: 2.5rem; font-weight: 800; color: var(--accent); line-height: 1.1; }
.stat-label { font-size: .9rem; color: var(--text-secondary); margin-top: .25rem; }

/* --- Section --- */
.section { padding: 4rem 0; }
.section-alt { background: var(--bg-light); }
.section-title { text-align: center; margin-bottom: .5rem; }
.section-subtitle {
  text-align: center; color: var(--text-secondary);
  max-width: 700px; margin: 0 auto 2.5rem;
}

/* --- Card Grid --- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}
.card {
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 1.75rem;
  transition: box-shadow var(--transition), transform var(--transition);
}
.card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.card h3 a { color: var(--text-main); }
.card h3 a:hover { color: var(--accent); }
.card p { color: var(--text-secondary); font-size: .9rem; }

/* Direction Card */
.direction-card {
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 2rem;
  transition: box-shadow var(--transition), transform var(--transition);
  display: flex; flex-direction: column;
}
.direction-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }
.direction-card .card-icon {
  width: 56px; height: 56px; border-radius: var(--radius);
  background: var(--bg-light); display: flex; align-items: center;
  justify-content: center; margin-bottom: 1rem; color: var(--accent);
}
.direction-card .card-icon svg { width: 28px; height: 28px; }
.direction-card h3 { margin-bottom: .5rem; }
.direction-card h3 a { color: var(--text-main); text-decoration: none; }
.direction-card h3 a:hover { color: var(--accent); }
.direction-card p { color: var(--text-secondary); font-size: .9rem; flex: 1; }
.direction-card .card-link {
  margin-top: 1rem; font-weight: 600; font-size: .9rem; color: var(--accent);
}

/* --- Breadcrumb --- */
.breadcrumb {
  padding: 1rem 0; font-size: .85rem; color: var(--text-secondary);
}
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb span { margin: 0 .4rem; }

/* --- CTA Section --- */
.cta-section {
  padding: 4rem 0; background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: var(--text-white); text-align: center;
}
.cta-section h2 { color: var(--text-white); margin-bottom: .75rem; }
.cta-section p { color: rgba(255,255,255,.85); max-width: 600px; margin: 0 auto 1.5rem; }

/* --- Diagram Container --- */
.diagram-container {
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 2rem;
  margin: 2rem 0; overflow-x: auto;
}
.diagram-container svg { display: block; margin: 0 auto; max-width: 100%; height: auto; }

/* --- Competence Grid --- */
.competence-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}
.competence-item {
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.25rem;
  display: flex; gap: .75rem; align-items: flex-start;
}
.competence-item .num {
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--accent); color: var(--text-white);
  display: flex; align-items: center; justify-content: center;
  font-size: .8rem; font-weight: 700; flex-shrink: 0;
}
.competence-item .label { font-size: .85rem; font-weight: 500; }

/* --- Feature List --- */
.feature-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; }
.feature-item { display: flex; gap: 1rem; align-items: flex-start; }
.feature-item .icon {
  width: 40px; height: 40px; border-radius: var(--radius);
  background: #EEF2FF; display: flex; align-items: center;
  justify-content: center; flex-shrink: 0; color: var(--accent);
}
.feature-item .icon svg { width: 20px; height: 20px; }
.feature-item h4 { margin-bottom: .25rem; font-size: 1rem; }
.feature-item p { font-size: .85rem; color: var(--text-secondary); margin: 0; }

/* --- Table --- */
.content-table {
  width: 100%; border-collapse: collapse; margin: 1.5rem 0;
  font-size: .9rem;
}
.content-table th {
  background: var(--primary); color: var(--text-white);
  padding: .75rem 1rem; text-align: left; font-weight: 600;
}
.content-table td {
  padding: .75rem 1rem; border-bottom: 1px solid var(--border);
  vertical-align: top;
}
.content-table tr:hover td { background: var(--bg-light); }

/* --- Research Block --- */
.research-block {
  display: flex; gap: 2rem; align-items: center;
  background: var(--bg-light); border-radius: var(--radius-lg);
  padding: 2rem;
}
.research-block img { width: 180px; border-radius: var(--radius); flex-shrink: 0; }
.research-block h3 { margin-bottom: .5rem; }

/* --- Use Case List --- */
.use-case-list { margin: 1.5rem 0; }
.use-case-list li {
  padding: .75rem 0 .75rem 1.5rem; position: relative;
  border-bottom: 1px solid var(--border);
}
.use-case-list li::before {
  content: ''; position: absolute; left: 0; top: 1.1rem;
  width: 8px; height: 8px; background: var(--accent);
  border-radius: 50%;
}

/* --- Prose (detail pages) --- */
.prose { max-width: 800px; }
.prose h2 { margin-top: 2.5rem; margin-bottom: 1rem; }
.prose h3 { margin-top: 2rem; }
.prose ul, .prose ol { margin: 1rem 0 1rem 1.5rem; }
.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: .5rem; color: var(--text-secondary); }
.prose li strong { color: var(--text-main); }
.prose blockquote {
  border-left: 4px solid var(--accent); padding: 1rem 1.5rem;
  background: var(--bg-light); border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.5rem 0; font-style: italic; color: var(--text-secondary);
}
.prose .highlight-box {
  background: #EEF2FF; border: 1px solid #C7D2FE;
  border-radius: var(--radius); padding: 1.5rem; margin: 1.5rem 0;
}

/* --- Two Column Layout --- */
.two-col {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 2rem; align-items: start;
}

/* --- Footer --- */
.site-footer {
  background: var(--primary-dark); color: rgba(255,255,255,.75);
  padding: 3rem 0 1.5rem;
}
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 2rem; margin-bottom: 2rem;
}
.footer-grid h4 { color: var(--text-white); margin-bottom: 1rem; font-size: .95rem; }
.footer-grid a { color: rgba(255,255,255,.65); font-size: .85rem; display: block; margin-bottom: .5rem; }
.footer-grid a:hover { color: var(--text-white); }
.footer-grid p { font-size: .85rem; line-height: 1.6; }
.footer-logo img { height: 36px; margin-bottom: .75rem; filter: brightness(0) invert(1); }
.footer-grid .footer-cta {
  display: inline-flex; align-items: center;
  background: var(--accent); color: var(--text-white);
  padding: .6rem 1.25rem; border-radius: var(--radius);
  font-size: .85rem; font-weight: 600; margin-top: 1rem;
  transition: background var(--transition);
}
.footer-grid .footer-cta:hover { background: #2563EB; color: var(--text-white); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.15);
  padding-top: 1.5rem; font-size: .8rem; text-align: center;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .main-nav { display: none; }
  .header-cta { display: none; }
  .hamburger { display: flex; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .two-col { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .stats-row { grid-template-columns: repeat(2, 1fr); gap: 1rem; }
  .card-grid { grid-template-columns: 1fr; }
  .hero { padding: 3rem 0; }
  .hero-home { padding: 3rem 0; }
  .section { padding: 2.5rem 0; }
  .footer-grid { grid-template-columns: 1fr; gap: 1.5rem; }
  .research-block { flex-direction: column; text-align: center; }
  .research-block img { width: 140px; }
  .competence-grid { grid-template-columns: 1fr 1fr; }
  h1 { font-size: 1.75rem; }
}

@media (max-width: 480px) {
  .stats-row { grid-template-columns: 1fr 1fr; }
  .competence-grid { grid-template-columns: 1fr; }
  .stat-number { font-size: 2rem; }
}

/* --- Product Logos --- */
.product-logo {
  height: 32px;
  width: auto;
  vertical-align: middle;
  margin-right: .5rem;
}
.product-logo-sm { height: 24px; }
.product-logo-lg { height: 48px; }
.hero .product-logo, .hero .product-logo-lg {
  filter: brightness(0) invert(1);
  opacity: .9;
  margin-right: .75rem;
}
.hero h1 .product-logo { height: 40px; margin-right: .5rem; vertical-align: baseline; }
.tech-logos {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  align-items: center;
  justify-content: center;
  padding: 1.5rem 0;
}
.tech-logos .tech-logo-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .5rem;
  font-size: .8rem;
  color: var(--text-secondary);
  font-weight: 500;
}
.tech-logos img, .tech-logos svg {
  height: 40px;
  width: auto;
}