/* ============================================================
   ImplIA — style.css
   Aesthetic: Refined editorial minimalism
   Fonts: DM Serif Display (headings) + DM Sans (body)
   Palette: Near-black, off-white, warm accent
   ============================================================ */

/* ── Custom Properties ── */
:root {
  /* Color */
  --ink:           #0e0e10;
  --ink-2:         #1c1c20;
  --ink-3:         #2e2e35;
  --muted:         #6b6b78;
  --muted-2:       #9898a6;
  --surface:       #fafaf8;
  --surface-2:     #f2f2ee;
  --surface-3:     #e8e8e2;
  --white:         #ffffff;
  --accent:        #1a1aff;   /* deep blue — minimal, used sparingly */
  --accent-warm:   #c8b89a;   /* warm tan for tags / accents */
  --border:        rgba(14,14,16,0.10);
  --border-strong: rgba(14,14,16,0.18);

  /* Type */
  --serif:  'DM Serif Display', Georgia, serif;
  --sans:   'DM Sans', system-ui, sans-serif;

  /* Sizing */
  --nav-h:      64px;
  --max-w:      1160px;
  --r:          4px;
  --r-lg:       10px;

  /* Motion */
  --ease:        cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in:     cubic-bezier(0.4, 0, 1, 1);
  --dur-fast:    160ms;
  --dur-med:     300ms;
  --dur-slow:    600ms;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body { font-family: var(--sans); background: var(--surface); color: var(--ink); line-height: 1.6; overflow-x: hidden; }
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font: inherit; cursor: pointer; border: none; background: none; }

/* ── Container ── */
.container {
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 48px);
}

/* ── Typography Scale ── */
h1, h2, h3, h4 { font-family: var(--serif); font-weight: 400; line-height: 1.1; letter-spacing: -0.01em; color: var(--ink); }
h1 { font-size: clamp(2.6rem, 6vw, 4.6rem); }
h2 { font-size: clamp(1.9rem, 3.5vw, 3rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.4rem); }
h4 { font-size: 1.1rem; }
p  { font-size: 1rem; line-height: 1.75; color: var(--muted); }

.italic { font-style: italic; }

/* ── Buttons ── */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 28px;
  background: var(--ink);
  color: var(--white);
  font-family: var(--sans);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  border-radius: var(--r);
  transition: background var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast);
}
.btn-primary:hover {
  background: var(--ink-2);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(14,14,16,0.18);
}
.btn-primary:active { transform: translateY(0); }
.btn-primary-lg { padding: 16px 36px; font-size: 1rem; }

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 13px 24px;
  background: transparent;
  color: var(--muted);
  font-family: var(--sans);
  font-size: 0.875rem;
  font-weight: 500;
  border: 1px solid var(--border-strong);
  border-radius: var(--r);
  transition: border-color var(--dur-fast), color var(--dur-fast), transform var(--dur-fast);
}
.btn-secondary:hover {
  border-color: var(--ink);
  color: var(--ink);
  transform: translateY(-1px);
}

.btn-cta {
  display: inline-flex;
  align-items: center;
  padding: 10px 22px;
  background: var(--ink);
  color: var(--white);
  font-size: 0.82rem;
  font-weight: 500;
  border-radius: var(--r);
  transition: background var(--dur-fast), transform var(--dur-fast);
}
.btn-cta:hover { background: var(--ink-2); transform: translateY(-1px); }

.btn-text-link {
  font-size: 0.9rem;
  color: var(--muted);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color var(--dur-fast);
}
.btn-text-link:hover { color: var(--ink); }


/* ============================================================
   HEADER / NAV
   ============================================================ */
.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 200;
  height: var(--nav-h);
  transition: background var(--dur-med) var(--ease), border-color var(--dur-med);
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: rgba(250,250,248,0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--border);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.wordmark {
  font-family: var(--serif);
  font-size: 1.45rem;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: -0.03em;
  flex-shrink: 0;
}
.wordmark span { color: var(--accent); }

.main-nav {
  display: flex;
  align-items: center;
  gap: 36px;
}
.nav-link {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--muted);
  position: relative;
  transition: color var(--dur-fast);
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--ink);
  transition: width var(--dur-med) var(--ease);
}
.nav-link:hover { color: var(--ink); }
.nav-link:hover::after,
.nav-link.active::after { width: 100%; }
.nav-link.active { color: var(--ink); }

.header-actions {
  display: flex;
  align-items: center;
  gap: 20px;
}

/* Language toggle */
.lang-toggle {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--muted);
  padding: 6px 0;
  transition: color var(--dur-fast);
}
.lang-toggle:hover { color: var(--ink); }
.lang-opt {
  padding: 2px 4px;
  border-radius: 2px;
  transition: color var(--dur-fast), background var(--dur-fast);
}
.lang-opt.active {
  color: var(--ink);
  font-weight: 600;
}
.lang-sep { color: var(--border-strong); }

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  padding: 4px;
  width: 32px;
  height: 32px;
}
.hamburger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--ink);
  transition: transform var(--dur-med) var(--ease), opacity var(--dur-med);
}
.hamburger.is-open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.hamburger.is-open span:nth-child(2) { transform: translateY(-7.5px) rotate(-45deg); }


/* ============================================================
   SECTIONS — shared
   ============================================================ */
.section { padding-block: clamp(72px, 10vw, 120px); }
.section-dark   { background: var(--ink); color: var(--surface); }
.section-tinted { background: var(--surface-2); }

.section-header { margin-bottom: 64px; }
.section-tag {
  display: inline-block;
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 24px;
}
.section-tag-light { color: rgba(250,250,248,0.45); }
.section-header-light h2 { color: var(--surface); }
.section-header h2 { max-width: 700px; }

/* Reveal on scroll */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
}
.reveal.in-view {
  opacity: 1;
  transform: translateY(0);
}


/* ============================================================
   HERO
   ============================================================ */
.hero {
  padding-top: calc(var(--nav-h) + clamp(64px, 10vw, 120px));
  padding-bottom: 0;
  overflow: hidden;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: end;
  padding-bottom: clamp(48px, 6vw, 80px);
}

.eyebrow {
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 24px;
}

.hero-heading {
  display: flex;
  flex-direction: column;
  margin-bottom: 28px;
}
.hero-heading .line {
  font-family: var(--serif);
  font-size: clamp(2.8rem, 6vw, 4.8rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
}

.hero-body {
  max-width: 500px;
  font-size: 1.05rem;
  margin-bottom: 36px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

/* Metric cards */
.hero-metrics {
  display: flex;
  flex-direction: column;
  gap: 2px;
  align-self: center;
  padding-bottom: 8px;
}

.metric-card {
  display: flex;
  flex-direction: column;
  padding: 28px 32px;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: var(--white);
  transition: border-color var(--dur-med), transform var(--dur-med) var(--ease);
}
.metric-card:hover { border-color: var(--border-strong); transform: translateX(4px); }

.metric-value {
  font-family: var(--serif);
  font-size: 2.8rem;
  line-height: 1;
  color: var(--ink);
  margin-bottom: 6px;
}
.metric-label {
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.4;
}

/* Rule bar */
.hero-rule {
  display: flex;
  align-items: center;
  gap: 20px;
  padding-block: 20px;
  border-top: 1px solid var(--border);
}
.rule-line { flex: 1; height: 1px; background: var(--border); }
.rule-text {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-2);
  white-space: nowrap;
}


/* ============================================================
   PROBLEM
   ============================================================ */
.problem-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  overflow: hidden;
}

.problem-item {
  background: var(--white);
  padding: 40px 32px;
  transition: background var(--dur-med);
}
.problem-item:hover { background: var(--surface-2); }

.problem-num {
  font-family: var(--serif);
  font-size: 2.2rem;
  color: var(--surface-3);
  line-height: 1;
  margin-bottom: 20px;
  font-style: italic;
}

.problem-item h3 {
  font-size: 1.05rem;
  margin-bottom: 12px;
}
.problem-item p { font-size: 0.93rem; }


/* ============================================================
   SOLUTIONS
   ============================================================ */
.solutions-list {
  display: flex;
  flex-direction: column;
}

.solution-row {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 40px;
  padding-block: 40px;
  border-bottom: 1px solid rgba(250,250,248,0.1);
  align-items: start;
  transition: opacity var(--dur-med);
}
.solution-row:last-child { border-bottom: none; }
.solution-row:hover { opacity: 0.92; }

.solution-index {
  font-family: var(--serif);
  font-size: 1.8rem;
  font-style: italic;
  color: rgba(250,250,248,0.2);
  line-height: 1;
  padding-top: 4px;
}

.solution-content h3 {
  color: var(--surface);
  margin-bottom: 12px;
  font-size: 1.25rem;
}
.solution-content > p {
  color: rgba(250,250,248,0.65);
  font-size: 0.95rem;
  max-width: 600px;
  margin-bottom: 20px;
}

.solution-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.solution-tags li {
  font-size: 0.78rem;
  font-weight: 500;
  color: rgba(250,250,248,0.5);
  border: 1px solid rgba(250,250,248,0.12);
  padding: 4px 12px;
  border-radius: 2px;
  letter-spacing: 0.02em;
}


/* ============================================================
   BENEFITS
   ============================================================ */
.benefits-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  overflow: hidden;
}

.benefit-card {
  background: var(--white);
  padding: 36px 28px;
  transition: background var(--dur-med);
}
.benefit-card:hover { background: var(--surface-2); }

.benefit-kpi {
  font-family: var(--serif);
  font-size: 2.6rem;
  line-height: 1;
  color: var(--ink);
  margin-bottom: 16px;
}

.benefit-card h3 {
  font-family: var(--sans);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink);
  margin-bottom: 10px;
}
.benefit-card p { font-size: 0.88rem; }


/* ============================================================
   USE CASES
   ============================================================ */
.cases-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.case-featured {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 48px 40px;
  grid-row: span 2;
  display: flex;
  flex-direction: column;
}

.case-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.case-sector {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  background: var(--surface-2);
  padding: 4px 10px;
  border-radius: 2px;
}

.case-result {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--ink);
  background: rgba(26,26,255,0.06);
  padding: 4px 10px;
  border-radius: 2px;
  letter-spacing: 0.02em;
}

.case-featured h3 {
  font-size: 1.4rem;
  margin-bottom: 16px;
}
.case-featured > p { margin-bottom: 32px; flex: 1; }

.case-stats {
  display: flex;
  gap: 28px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
  margin-top: auto;
}
.case-stats div { display: flex; flex-direction: column; gap: 4px; }
.case-stats strong { font-family: var(--serif); font-size: 1.8rem; font-weight: 400; color: var(--ink); line-height: 1; }
.case-stats span { font-size: 0.8rem; color: var(--muted); }

.cases-secondary {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.case-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color var(--dur-med), transform var(--dur-med) var(--ease);
}
.case-card:hover { border-color: var(--border-strong); transform: translateY(-2px); }

.case-card h4 { margin-bottom: 4px; font-size: 1rem; }
.case-card p { font-size: 0.88rem; }

.case-tag {
  display: inline-flex;
  align-self: flex-start;
  margin-top: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--ink);
  background: rgba(26,26,255,0.06);
  padding: 4px 10px;
  border-radius: 2px;
}


/* ============================================================
   ABOUT
   ============================================================ */
.about-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: start;
}

.about-text h2 { margin-bottom: 24px; }
.about-text p { margin-bottom: 16px; }

.about-details {
  margin-top: 36px;
  border-top: 1px solid var(--border);
  padding-top: 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.about-detail {
  display: flex;
  align-items: baseline;
  gap: 16px;
  font-size: 0.9rem;
}
.detail-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-2);
  min-width: 100px;
}
.detail-value { color: var(--ink); font-weight: 400; }

.principle-card {
  background: var(--ink);
  color: var(--surface);
  border-radius: var(--r-lg);
  padding: 40px 36px;
}
.principle-card h4 {
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(250,250,248,0.4);
  margin-bottom: 24px;
}
.principle-card ul { display: flex; flex-direction: column; gap: 0; }
.principle-card li {
  font-size: 0.92rem;
  color: rgba(250,250,248,0.8);
  line-height: 1.6;
  padding-block: 14px;
  border-bottom: 1px solid rgba(250,250,248,0.08);
  padding-left: 14px;
  position: relative;
}
.principle-card li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 4px;
  background: var(--accent);
  border-radius: 50%;
}
.principle-card li:last-child { border-bottom: none; }


/* ============================================================
   CTA
   ============================================================ */
.cta-section { background: var(--ink); }

.cta-block {
  max-width: 740px;
  margin-inline: auto;
  text-align: center;
  padding-block: 20px;
}

.cta-pre {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(250,250,248,0.3);
  margin-bottom: 24px;
}

.cta-heading {
  font-family: var(--serif);
  font-size: clamp(1.8rem, 4vw, 3rem);
  color: var(--surface);
  margin-bottom: 20px;
  line-height: 1.15;
}

.cta-sub {
  color: rgba(250,250,248,0.55);
  font-size: 1rem;
  margin-bottom: 44px;
  max-width: 560px;
  margin-inline: auto;
  margin-bottom: 44px;
}

.cta-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.cta-section .btn-primary {
  background: var(--surface);
  color: var(--ink);
}
.cta-section .btn-primary:hover { background: var(--white); }

.cta-section .btn-text-link { color: rgba(250,250,248,0.45); }
.cta-section .btn-text-link:hover { color: rgba(250,250,248,0.75); }


/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: var(--ink-2);
  border-top: 1px solid rgba(250,250,248,0.06);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 80px;
  padding-block: 64px;
}

.footer-left .wordmark { color: var(--surface); display: block; margin-bottom: 12px; }
.footer-left p { color: rgba(250,250,248,0.35); font-size: 0.88rem; margin-bottom: 6px; }
.footer-location { font-size: 0.8rem !important; color: rgba(250,250,248,0.2) !important; }

.footer-nav {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}

.footer-col { display: flex; flex-direction: column; gap: 12px; }
.footer-col-title {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(250,250,248,0.25) !important;
  margin-bottom: 4px;
}
.footer-col a {
  font-size: 0.88rem;
  color: rgba(250,250,248,0.5);
  transition: color var(--dur-fast);
}
.footer-col a:hover { color: rgba(250,250,248,0.9); }

.footer-bottom {
  border-top: 1px solid rgba(250,250,248,0.06);
  padding-block: 20px;
}
.footer-bottom .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-bottom span { font-size: 0.78rem; color: rgba(250,250,248,0.2); }


/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
  .hero-layout       { gap: 48px; }
  .benefits-grid     { grid-template-columns: repeat(2, 1fr); }
  .about-layout      { gap: 48px; }
}

@media (max-width: 900px) {
  .main-nav          { display: none; }
  .header-cta        { display: none; }
  .hamburger         { display: flex; }

  /* Mobile nav — appears as overlay */
  .main-nav.nav-open {
    display: flex;
    flex-direction: column;
    position: fixed;
    inset: var(--nav-h) 0 0;
    background: rgba(250,250,248,0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 40px clamp(20px, 4vw, 48px);
    gap: 28px;
    z-index: 199;
    border-top: 1px solid var(--border);
  }
  .main-nav.nav-open .nav-link {
    font-size: 1.2rem;
    color: var(--ink);
  }

  .hero-layout {
    grid-template-columns: 1fr;
    gap: 48px;
  }
  .hero-metrics {
    flex-direction: row;
    gap: 12px;
  }
  .metric-card { flex: 1; padding: 20px; }
  .metric-value { font-size: 2rem; }

  .problem-grid      { grid-template-columns: 1fr; }
  .solutions-list .solution-row { grid-template-columns: 48px 1fr; gap: 20px; }
  .cases-layout      { grid-template-columns: 1fr; }
  .case-featured     { grid-row: span 1; }
  .about-layout      { grid-template-columns: 1fr; gap: 40px; }
  .footer-inner      { grid-template-columns: 1fr; gap: 48px; }
}

@media (max-width: 620px) {
  .hero-metrics      { flex-direction: column; }
  .benefits-grid     { grid-template-columns: 1fr; }
  .case-stats        { flex-wrap: wrap; gap: 20px; }
  .hero-actions      { flex-direction: column; align-items: flex-start; }
  .footer-nav        { grid-template-columns: 1fr; }
  .footer-bottom .container { flex-direction: column; gap: 6px; text-align: center; }
}