/* ═══════════════════════════════════════════════════════════════
   QUIET INTELLIGENCE — Design System
   Editorial minimalism + technical precision + personal identity
   Anthropic calmness × BBC editorial × Palantir IA × Alwin
   ═══════════════════════════════════════════════════════════════ */

/* ── Design Tokens ───────────────────────────────────────────── */
:root {
  /* Color */
  --bg:       #F8F8F6;
  --surface:  #F0EFED;
  --border:   #E4E3E0;
  --text:     #1A1A19;
  --text-2:   #6B6B66;
  --text-3:   #9C9C96;
  --accent:   #4A90D9;
  --accent-h: #3A7BC8;
  --dark:     #1A1A19;
  --dark-2:   #2A2A28;
  --white:    #FAFAF8;

  /* Typography */
  --sans:   'Inter', system-ui, -apple-system, sans-serif;
  --serif:  'Instrument Serif', Georgia, 'Times New Roman', serif;
  --mono:   'DM Mono', 'SF Mono', 'Fira Code', monospace;

  /* Spacing */
  --space-xs:  8px;
  --space-sm:  16px;
  --space-md:  24px;
  --space-lg:  40px;
  --space-xl:  64px;
  --space-2xl: 96px;
  --space-3xl: 140px;

  /* Layout */
  --max-w:    1120px;
  --gutter:   clamp(20px, 5vw, 60px);

  /* Animation */
  --ease:     cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 200ms;
  --dur-med:  400ms;
  --dur-slow: 600ms;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; }
a { color: inherit; }
button { font: inherit; border: none; background: none; cursor: pointer; }

/* ── Typography ──────────────────────────────────────────────── */
.t-display {
  font-family: var(--serif);
  font-size: clamp(48px, 8vw, 96px);
  font-weight: 400;
  line-height: 1.0;
  letter-spacing: -0.02em;
  color: var(--text);
}

.t-h1 {
  font-family: var(--sans);
  font-size: clamp(36px, 5vw, 64px);
  font-weight: 200;
  line-height: 1.08;
  letter-spacing: -0.03em;
}

.t-h2 {
  font-family: var(--sans);
  font-size: clamp(28px, 3.5vw, 44px);
  font-weight: 300;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.t-h3 {
  font-family: var(--sans);
  font-size: clamp(20px, 2.2vw, 28px);
  font-weight: 300;
  line-height: 1.25;
  letter-spacing: -0.015em;
}

.t-body {
  font-size: 16px;
  font-weight: 300;
  line-height: 1.75;
  color: var(--text-2);
}

.t-body-lg {
  font-size: clamp(17px, 1.4vw, 20px);
  font-weight: 300;
  line-height: 1.7;
  color: var(--text-2);
}

.t-small {
  font-size: 13px;
  font-weight: 400;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-3);
}

.t-label {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 300;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
}

/* ── Layout ──────────────────────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.section {
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-2xl);
}

.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 0;
}

/* ── Header / Navigation ─────────────────────────────────────── */
.qi-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(248, 248, 246, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 0 var(--gutter);
}

.qi-header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}

.qi-brand {
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--text);
}

.qi-nav {
  display: flex;
  align-items: center;
  gap: 36px;
}

.qi-nav a {
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--text-2);
  transition: color var(--dur-fast) ease;
  position: relative;
}

.qi-nav a:hover,
.qi-nav a.active {
  color: var(--text);
}

.qi-nav a.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--text);
}

.qi-nav .ext {
  color: var(--text-3);
  display: flex;
  align-items: center;
  gap: 4px;
}

.qi-nav .ext:hover { color: var(--text); }

/* Mobile hamburger */
.qi-ham {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
  z-index: 101;
}

.qi-ham span {
  display: block;
  width: 22px;
  height: 1px;
  background: var(--text);
  transition: transform 0.3s var(--ease);
}

/* Mobile nav overlay */
.qi-mnav {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--bg);
  z-index: 99;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 32px;
  opacity: 0;
  transition: opacity 0.4s var(--ease);
}

.qi-mnav.open { opacity: 1; }

.qi-mnav a {
  font-size: clamp(24px, 5vw, 40px);
  font-weight: 200;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--text);
  transition: color var(--dur-fast) ease;
}

.qi-mnav a:hover { color: var(--accent); }

/* ── Footer ──────────────────────────────────────────────────── */
.qi-footer {
  border-top: 1px solid var(--border);
  padding: var(--space-xl) var(--gutter);
  text-align: center;
}

.qi-footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.qi-footer-name {
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text);
  margin-bottom: 8px;
}

.qi-footer-role {
  font-size: 13px;
  font-weight: 300;
  color: var(--text-3);
  margin-bottom: var(--space-md);
}

.qi-footer-projects {
  font-size: 12px;
  font-weight: 300;
  color: var(--text-3);
  margin-bottom: var(--space-lg);
  letter-spacing: 0.04em;
}

.qi-footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 24px;
  margin-bottom: var(--space-md);
}

.qi-footer-links a {
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--text-3);
  transition: color var(--dur-fast) ease;
}

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

.qi-footer-copy {
  font-family: var(--mono);
  font-size: 10px;
  color: var(--text-3);
  letter-spacing: 0.08em;
  margin-top: var(--space-md);
}

/* ── Editorial Project List ──────────────────────────────────── */
.ed-list {
  border-top: 1px solid var(--border);
}

.ed-item {
  display: grid;
  grid-template-columns: 48px 1fr auto;
  gap: var(--space-lg);
  padding: var(--space-lg) 0;
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  color: inherit;
  transition: padding-left var(--dur-med) var(--ease);
}

.ed-item:hover {
  padding-left: 12px;
}

.ed-num {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-3);
  letter-spacing: 0.08em;
  padding-top: 6px;
}

.ed-title {
  font-size: clamp(22px, 3vw, 36px);
  font-weight: 200;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 6px;
  line-height: 1.15;
}

.ed-meta {
  font-size: 13px;
  font-weight: 300;
  color: var(--text-3);
  margin-bottom: 4px;
}

.ed-tech {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text-3);
  letter-spacing: 0.06em;
}

.ed-arrow {
  font-size: 18px;
  color: var(--text-3);
  padding-top: 8px;
  transition: transform var(--dur-fast) var(--ease), color var(--dur-fast) ease;
}

.ed-item:hover .ed-arrow {
  transform: translateX(4px);
  color: var(--text);
}

/* ── News / Journal Items ────────────────────────────────────── */
.news-list {
  border-top: 1px solid var(--border);
}

.news-item {
  display: block;
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  color: inherit;
  transition: padding-left var(--dur-med) var(--ease);
}

.news-item:hover { padding-left: 12px; }

.news-date {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-3);
  margin-bottom: 6px;
}

.news-tag {
  display: inline-block;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-left: 12px;
}

.news-headline {
  font-size: clamp(18px, 2.2vw, 26px);
  font-weight: 300;
  letter-spacing: -0.015em;
  color: var(--text);
  line-height: 1.3;
}

.news-excerpt {
  font-size: 14px;
  font-weight: 300;
  color: var(--text-3);
  margin-top: 6px;
  line-height: 1.6;
}

/* ── Category Filters ────────────────────────────────────────── */
.cat-filters {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
}

.cat-filters button {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 6px 0;
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) ease, border-color var(--dur-fast) ease;
}

.cat-filters button:hover,
.cat-filters button.active {
  color: var(--text);
  border-color: var(--text);
}

/* ── Case Study Meta Bar ─────────────────────────────────────── */
.case-meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  margin-bottom: var(--space-xl);
}

.case-meta-item {}

.case-meta-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 4px;
}

.case-meta-val {
  font-size: 14px;
  font-weight: 400;
  color: var(--text);
}

/* ── Case Study Sections ─────────────────────────────────────── */
.case-section {
  margin-bottom: var(--space-xl);
}

.case-section-title {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: var(--space-sm);
}

.case-section p {
  font-size: 16px;
  font-weight: 300;
  line-height: 1.8;
  color: var(--text-2);
  max-width: 680px;
}

/* ── Timeline ────────────────────────────────────────────────── */
.timeline {
  border-top: 1px solid var(--border);
}

.tl-item {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: var(--space-lg);
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--border);
}

.tl-year {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-3);
  letter-spacing: 0.08em;
  padding-top: 2px;
}

.tl-title {
  font-size: 18px;
  font-weight: 300;
  color: var(--text);
  margin-bottom: 4px;
}

.tl-desc {
  font-size: 14px;
  font-weight: 300;
  color: var(--text-3);
  line-height: 1.6;
}

/* ── ⌘K Search Modal ─────────────────────────────────────────── */
.search-trigger {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text-3);
  letter-spacing: 0.06em;
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 4px;
  transition: border-color var(--dur-fast) ease, color var(--dur-fast) ease;
}

.search-trigger:hover {
  border-color: var(--text-3);
  color: var(--text-2);
}

.search-overlay {
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  position: fixed;
  inset: 0;
  background: rgba(26, 26, 25, 0.4);
  backdrop-filter: blur(4px);
  z-index: 200;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding-top: 15vh;
  transition: opacity var(--dur-fast) var(--ease), visibility var(--dur-fast) var(--ease);
}

.search-overlay.open {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
}

.search-box {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  width: min(560px, 90vw);
  box-shadow: 0 24px 80px rgba(0,0,0,0.12);
  overflow: hidden;
}

.search-input-wrap {
  display: flex;
  align-items: center;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  gap: 12px;
}

.search-icon {
  font-size: 16px;
  color: var(--text-3);
  flex-shrink: 0;
}

.search-input {
  flex: 1;
  border: none;
  background: none;
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 300;
  color: var(--text);
  outline: none;
}

.search-input::placeholder { color: var(--text-3); }

.search-results {
  max-height: 360px;
  overflow-y: auto;
  padding: 8px 0;
}

.search-results:empty::after {
  content: 'Type to search...';
  display: block;
  padding: 24px 20px;
  font-size: 14px;
  color: var(--text-3);
}

.search-cat {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 12px 20px 4px;
}

.search-result {
  display: block;
  padding: 10px 20px;
  text-decoration: none;
  color: var(--text);
  font-size: 14px;
  font-weight: 300;
  transition: background var(--dur-fast) ease;
}

.search-result:hover {
  background: var(--surface);
}

/* ── Scroll Reveal ───────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
}

.reveal.in {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ── Responsive ──────────────────────────────────────────────── */
@media (max-width: 1023px) {
  .case-meta {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 767px) {
  .qi-nav { display: none; }
  .qi-ham { display: flex; }

  .ed-item {
    grid-template-columns: 32px 1fr;
    gap: var(--space-sm);
  }
  .ed-arrow { display: none; }

  .case-meta {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .tl-item {
    grid-template-columns: 1fr;
    gap: 4px;
  }

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

/* ── Accessibility ────────────────────────────────────────────── */
:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; border-radius: 2px; }