/* =========================================
   DESIGN SYSTEM: Tufte Clarity + Norman UX
   - High data-ink ratio UI
   - Consistent affordances & visibility
   - Generous whitespace & typographic hierarchy
   ========================================= */
:root {
  /* Palette */
  --bg: #F9FAFB;
  --surface: #FFFFFF;
  --text-primary: #0F172A;
  --text-secondary: #475569;
  --text-muted: #64748B;
  --border: #E2E8F0;
  --accent: #0F172A;
  --accent-hover: #1E293B;
  --highlight: #2563EB;
  --highlight-light: #EFF6FF;

  /* Typography */
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;

  /* Spacing & Layout */
  --space-unit: 8px;
  --max-width: 1200px;
  --nav-height: 72px;
  --radius: 6px;

  /* Transitions */
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --duration: 0.6s;
}

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

html, body {
  background:
    radial-gradient(ellipse 70% 50% at 80% 20%, rgba(219, 234, 254, 0.4), transparent),
    radial-gradient(ellipse 60% 40% at 10% 80%, rgba(254, 243, 199, 0.4), transparent),
    var(--bg);
  background-attachment: fixed;
  min-height: 100vh;
  color: var(--text-primary);
  font-family: var(--font-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* ── Layout ── */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 calc(var(--space-unit) * 3);
}

/* ── Navigation (Norman: Visibility + Consistent Mapping) ── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(249, 250, 251, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.nav-logo {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}
.nav-links { display: flex; gap: calc(var(--space-unit) * 3); list-style: none; }
.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  padding: calc(var(--space-unit) * 1) 0;
  position: relative;
  transition: color var(--duration) var(--ease-out-expo);
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0;
  width: 0; height: 1px;
  background: var(--accent);
  transition: width var(--duration) var(--ease-out-expo);
}
.nav-link:hover,
.nav-link.active { color: var(--text-primary); }
.nav-link.active::after,
.nav-link:hover::after { width: 100%; }

/* ── Hero ── */
.hero {
  padding-top: calc(var(--nav-height) + 80px);
  padding-bottom: 80px;
  min-height: 90vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.hero-eyebrow {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 20px;
  font-family: var(--font-mono);
}
.hero-title {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}
.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  max-width: 600px;
  margin-bottom: 40px;
  line-height: 1.7;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }
.hero-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.hero-meta span { display: flex; align-items: center; gap: 8px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 80px;
  align-items: center;
}
.hero-photo {
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero-photo img { 
  width: 100%; 
  height: auto; 
  display: block; 
  mix-blend-mode: multiply;
}
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 10px;
  background: #F2FBF6;
  color: #34D399;
  font-size: 0.78rem;
  font-weight: 500;
  border-radius: 4px;
  margin-top: 12px;
}

/* ── Buttons (Norman: Clear Affordances & Feedback) ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  font-weight: 500;
  font-size: 0.9rem;
  text-decoration: none;
  border-radius: var(--radius);
  transition: all var(--duration) var(--ease-out-expo);
  cursor: pointer;
  border: 1px solid transparent;
  font-family: var(--font-main);
}
.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-2px); }
.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border);
}
.btn-secondary:hover { border-color: var(--text-primary); transform: translateY(-2px); }

/* ── Stats Grid (Tufte: Maximize Data-Ink) ── */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  margin: 64px 0;
  border-top: 1px solid var(--border);
  padding-top: 40px;
}
.stat-card {
  background: var(--surface);
  padding: 28px 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.stat-value {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  color: var(--text-primary);
  line-height: 1;
  margin-bottom: 6px;
}
.stat-label { color: var(--text-muted); font-size: 0.875rem; }

/* ── Sections ── */
.section { padding: 80px 0; border-bottom: 1px solid var(--border); }
.section:last-child { border-bottom: none; }
.section-label {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}
.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}
.section-lead {
  color: var(--text-secondary);
  max-width: 640px;
  margin-bottom: 48px;
  font-size: 1rem;
  line-height: 1.7;
}

/* ── Cards ── */
.card-grid { display: grid; gap: 20px; }
.card-grid-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.card-grid-4 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 28px 32px;
  border-radius: var(--radius);
  transition: box-shadow var(--duration) var(--ease-out-expo),
              transform var(--duration) var(--ease-out-expo);
}
.card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.06);
  transform: translateY(-3px);
}
.card-tag {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 10px;
}
.card-title { font-size: 1.15rem; font-weight: 600; margin-bottom: 8px; letter-spacing: -0.01em; }
.card-date { font-size: 0.82rem; color: var(--text-muted); font-family: var(--font-mono); margin-bottom: 14px; }
.card-text { color: var(--text-secondary); font-size: 0.93rem; line-height: 1.65; margin-bottom: 20px; }
.tag-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.tag {
  padding: 4px 10px;
  background: var(--highlight-light);
  color: var(--highlight);
  font-size: 0.78rem;
  font-weight: 500;
  border-radius: 4px;
  font-family: var(--font-mono);
}
.view-doc-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--highlight);
  text-decoration: none;
  border: 1px solid var(--highlight-light);
  padding: 6px 14px;
  border-radius: 4px;
  background: var(--highlight-light);
  transition: all 0.25s;
}
.view-doc-btn:hover { background: #dbeafe; border-color: #bfdbfe; }
.distinction-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  background: #F2FBF6;
  color: #34D399;
  font-size: 0.78rem;
  font-weight: 600;
  border-radius: 4px;
  margin-left: 12px;
}

/* ── Skills (Norman: Grouping + Consistency) ── */
.skill-category { margin-bottom: 36px; }
.skill-title {
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 14px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}
.skill-list { list-style: none; display: flex; flex-wrap: wrap; gap: 10px; }
.skill-item {
  padding: 6px 14px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: border-color 0.2s, color 0.2s;
}
.skill-item:hover { border-color: var(--text-primary); color: var(--text-primary); }

/* ── Timeline ── */
.timeline { margin-top: 8px; }
.timeline-item {
  position: relative;
  padding-left: 28px;
  padding-bottom: 40px;
  border-left: 1px solid var(--border);
}
.timeline-item:last-child { border-left: 1px solid transparent; padding-bottom: 0; }
.timeline-item::before {
  content: '';
  position: absolute;
  left: -5px; top: 4px;
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--surface);
  border: 2px solid var(--text-primary);
}
.timeline-company {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 4px;
}
.timeline-role {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}
.timeline-period {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 14px;
}
.timeline-list { list-style: none; padding: 0; }
.timeline-list li {
  font-size: 0.93rem;
  color: var(--text-secondary);
  padding: 7px 0 7px 18px;
  border-bottom: 1px solid var(--border);
  position: relative;
  line-height: 1.6;
}
.timeline-list li:last-child { border-bottom: none; }
.timeline-list li::before {
  content: '→';
  position: absolute; left: 0;
  color: var(--highlight);
  font-size: 0.85rem;
}

/* ── Case Study Cards (case-studies.html) ── */
.page-header-section {
  padding-top: calc(var(--nav-height) + 60px);
  padding-bottom: 48px;
  border-bottom: 1px solid var(--border);
}
.contact-section {
  /* Inherits body background */
}
.page-header-section .hero-eyebrow { margin-bottom: 16px; }
.page-header-section .hero-title { margin-bottom: 16px; }

.case-section-label {
  padding: 48px 0 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.case-section-label span:first-child {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  white-space: nowrap;
}
.case-section-label .rule { flex: 1; height: 1px; background: var(--border); }

/* Accordion Case Card */
.case-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 16px;
  overflow: hidden;
  transition: box-shadow var(--duration) var(--ease-out-expo);
}
.case-card:hover { box-shadow: 0 4px 20px rgba(0,0,0,0.06); }

.case-card-summary {
  padding: 32px 36px 24px;
  display: grid;
  grid-template-columns: 1fr 220px;
  gap: 32px;
  align-items: start;
  cursor: pointer;
}
.card-domain {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 10px;
}
.case-card-title {
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 12px;
}
.case-card-sit {
  font-size: 0.93rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.tech-pill {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-top: 14px;
  display: block;
}

/* Signal Stat */
.signal-stat {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 18px;
}
.stat-num {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
  display: block;
  margin-bottom: 8px;
  letter-spacing: -0.04em;
}
.stat-lbl {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.5;
  display: block;
}

/* Toggle Button */
.toggle-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 14px 36px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-muted);
  background: none;
  border: none;
  border-top: 1px solid var(--border);
  cursor: pointer;
  transition: color 0.25s, background 0.25s;
  font-family: var(--font-main);
}
.toggle-btn:hover { color: var(--text-primary); background: var(--bg); }
.toggle-icon { transition: transform 0.3s; margin-left: auto; font-style: normal; }
.case-card.open .toggle-icon { transform: rotate(180deg); }
.case-card.open .toggle-btn { color: var(--highlight); }

/* Expanded Detail */
.card-detail {
  display: none;
  padding: 32px 36px 36px;
  border-top: 1px solid var(--border);
}
.case-card.open .card-detail { display: block; }

.detail-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 28px;
}
.detail-block h4 {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.detail-block p { font-size: 0.93rem; color: var(--text-secondary); line-height: 1.7; }

/* Outcome block */
.outcome-block {
  background: #F0FDF4;
  border: 1px solid #DCFCE7;
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 28px;
}
.outcome-block h4 {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #34D399;
  font-family: var(--font-mono);
  margin-bottom: 20px;
}
.outcome-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 20px;
}
.o-num {
  font-size: 1.65rem;
  font-weight: 700;
  color: #34D399;
  display: block;
  line-height: 1;
  letter-spacing: -0.03em;
}
.o-label {
  font-size: 0.82rem;
  color: var(--text-secondary);
  display: block;
  margin-top: 4px;
  line-height: 1.4;
}
.o-context {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: block;
  margin-top: 2px;
  font-style: italic;
}

/* Insights block */
.insights-block h4 {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.insights-block ul { list-style: none; }
.insights-block li {
  font-size: 0.93rem;
  color: var(--text-secondary);
  padding: 8px 0 8px 20px;
  border-bottom: 1px solid var(--border);
  position: relative;
  line-height: 1.6;
}
.insights-block li:last-child { border-bottom: none; }
.insights-block li::before {
  content: '→';
  position: absolute; left: 0;
  color: var(--highlight);
  font-size: 0.85rem;
}

.method-note {
  margin-top: 20px;
  font-size: 0.78rem;
  color: var(--text-muted);
  font-style: italic;
  padding-top: 14px;
  border-top: 1px solid var(--border);
  font-family: var(--font-mono);
}

/* Image Showcase */
.image-showcase {
  margin: 24px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.image-showcase h4 {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.image-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}
.image-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}
.image-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
  background: var(--bg);
}
.image-caption { padding: 12px 14px; border-top: 1px solid var(--border); }
.image-caption strong {
  display: block;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
}
.image-caption span { font-size: 0.78rem; color: var(--text-muted); font-style: italic; line-height: 1.5; }

/* ── Footer ── */
.footer {
  padding: 60px 0 40px;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}
.footer-name {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  display: block;
  margin-bottom: 4px;
  letter-spacing: -0.02em;
}
.footer-role {
  display: block;
  margin-bottom: 6px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}
.footer-tagline {
  display: block;
  margin-bottom: 24px;
  font-size: 0.82rem;
  color: var(--text-muted);
  font-style: italic;
}
.footer-links { display: flex; justify-content: center; gap: 24px; margin-bottom: 24px; }
.footer-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.25s;
}
.footer-links a:hover { color: var(--text-primary); }
.footer-copy { font-size: 0.8rem; color: var(--text-muted); }

/* ── Responsive ── */
@media (max-width: 768px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .hero-photo { max-width: 260px; }
  .hero { padding-top: 100px; min-height: auto; }
  .nav-links { display: none; }
  .case-card-summary { grid-template-columns: 1fr; gap: 20px; padding: 24px 20px 16px; }
  .card-detail { padding: 20px; }
  .detail-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr; gap: 16px; margin: 40px 0; padding-top: 32px; }
  .stat-card { padding: 20px 24px; }
  .footer-links { flex-wrap: wrap; gap: 16px; }
}