/* ============================================
   VQAA Media — Design System
   Entity Engineering / Knowledge Graph Construction
   ============================================ */

:root {
  /* Color tokens */
  --color-primary: #1E5F8C;       /* deep blue — headers, links */
  --color-accent: #4FA8D8;        /* light blue — highlights, buttons */
  --color-verified: #10B981;      /* green — "entity verified" cue, used sparingly */
  --color-ink: #0A0E14;           /* near-black text */
  --color-ink-soft: #3D4A5C;      /* secondary text */
  --color-bg: #F7FAFC;            /* page background */
  --color-bg-card: #FFFFFF;       /* card / panel background */
  --color-border: #DCE6EF;        /* hairline borders */

  /* Type */
  --font-display: 'Söhne', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Charter', 'Georgia', 'Iowan Old Style', serif;
  --font-utility: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Layout */
  --max-width: 1100px;
  --radius: 6px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(10, 14, 20, 0.04), 0 1px 3px rgba(10, 14, 20, 0.06);
  --shadow-md: 0 2px 8px rgba(10, 14, 20, 0.06), 0 8px 24px rgba(30, 95, 140, 0.06);
  --shadow-lg: 0 4px 16px rgba(10, 14, 20, 0.08), 0 16px 40px rgba(30, 95, 140, 0.10);
  --shadow-hover: 0 8px 24px rgba(10, 14, 20, 0.10), 0 20px 48px rgba(30, 95, 140, 0.12);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.65;
  font-size: 17px;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--color-ink);
  line-height: 1.2;
  margin: 0 0 0.5em;
}

h1 { font-size: clamp(2rem, 5vw, 3.2rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); letter-spacing: -0.01em; }
h3 { font-size: 1.3rem; }

p { margin: 0 0 1.2em; color: var(--color-ink-soft); }

a {
  color: var(--color-primary);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

img { max-width: 100%; display: block; }

/* ============ Layout ============ */

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ============ Header ============ */

.site-header {
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 14px;
  padding-bottom: 14px;
  gap: 24px;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--color-ink);
}
.logo-link img { height: 40px; width: auto; }
.logo-link:hover { text-decoration: none; }

.main-nav {
  display: flex;
  gap: 28px;
  align-items: center;
  font-family: var(--font-utility);
  font-size: 0.95rem;
  font-weight: 500;
}
.main-nav a { color: var(--color-ink-soft); }
.main-nav a:hover { color: var(--color-primary); text-decoration: none; }
.main-nav a.cta {
  background: var(--color-primary);
  color: #fff;
  padding: 9px 18px;
  border-radius: var(--radius);
}
.main-nav a.cta:hover { background: var(--color-accent); }

.nav-toggle { display: none; }

@media (max-width: 720px) {
  .main-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg-card);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    align-items: flex-start;
    padding: 16px 24px 24px;
    gap: 16px;
  }
  .main-nav.open { display: flex; }
  .nav-toggle {
    display: block;
    background: none;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 8px 12px;
    font-family: var(--font-utility);
    font-size: 0.9rem;
    cursor: pointer;
  }
}

/* ============ Hero ============ */

.hero {
  padding: 72px 0 56px;
  background: linear-gradient(180deg, #EEF6FB 0%, var(--color-bg) 100%);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  overflow: hidden;
}

.hero .eyebrow {
  font-family: var(--font-utility);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-primary);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero .eyebrow .dot {
  width: 8px; height: 8px;
  background: var(--color-verified);
  border-radius: 50%;
  display: inline-block;
}

.hero h1 { max-width: 14ch; }
.hero .lead {
  font-family: var(--font-utility);
  font-size: 1.15rem;
  color: var(--color-ink-soft);
  max-width: 46ch;
  margin-top: 18px;
}

.hero-actions { display: flex; gap: 14px; margin-top: 28px; flex-wrap: wrap; }

.btn {
  font-family: var(--font-utility);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 26px;
  border-radius: var(--radius);
  display: inline-block;
  border: 1px solid transparent;
  cursor: pointer;
  transition: box-shadow 0.2s ease, transform 0.2s ease, background 0.2s ease;
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
  box-shadow: 0 2px 8px rgba(30, 95, 140, 0.25);
}
.btn-primary:hover {
  background: var(--color-accent);
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(79, 168, 216, 0.35);
  transform: translateY(-1px);
}
.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-border);
}
.btn-secondary:hover {
  border-color: var(--color-primary);
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transform: translateY(-1px);
}

/* Node/network signature graphic */
.node-graphic {
  position: absolute;
  right: -60px;
  top: 40px;
  width: 380px;
  height: 280px;
  opacity: 0.5;
  pointer-events: none;
  filter: drop-shadow(0 4px 12px rgba(30, 95, 140, 0.15));
}
@media (max-width: 900px) { .node-graphic { display: none; } }

/* ============ Sections ============ */

.section { padding: 64px 0; }
.section-alt { background: var(--color-bg-card); border-top: 1px solid var(--color-border); border-bottom: 1px solid var(--color-border); }

.section-head { max-width: 60ch; margin-bottom: 40px; }
.section-head .eyebrow {
  font-family: var(--font-utility);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-primary);
  margin-bottom: 10px;
  display: block;
}

/* ============ Cards / Grid ============ */

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
@media (max-width: 800px) {
  .grid-3, .grid-2 { grid-template-columns: 1fr; }
}

.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.card h3 { margin-bottom: 10px; }
.card p { margin-bottom: 0; font-size: 0.98rem; }

.card .num {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--color-accent);
  letter-spacing: 0.08em;
  margin-bottom: 10px;
  display: block;
}

/* ============ Article list ============ */

.article-list { display: flex; flex-direction: column; gap: 0; }
.article-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 24px;
  padding: 20px 24px;
  margin: 0 -24px;
  border-bottom: 1px solid var(--color-border);
  font-family: var(--font-utility);
  border-radius: var(--radius);
  transition: box-shadow 0.2s ease, background 0.2s ease;
}
.article-row:hover {
  background: var(--color-bg-card);
  box-shadow: var(--shadow-sm);
}
.article-row:first-child { border-top: 1px solid var(--color-border); }
.article-row a {
  color: var(--color-ink);
  font-weight: 600;
  font-size: 1.02rem;
}
.article-row a:hover { color: var(--color-primary); }
.article-row .tag {
  font-size: 0.8rem;
  color: var(--color-ink-soft);
  white-space: nowrap;
  font-weight: 400;
}

/* ============ Article page ============ */

.article-header {
  padding: 56px 0 32px;
  border-bottom: 1px solid var(--color-border);
}
.article-header .eyebrow {
  font-family: var(--font-utility);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-primary);
  margin-bottom: 12px;
  display: block;
}
.article-header h1 { max-width: 22ch; }
.article-meta {
  font-family: var(--font-utility);
  font-size: 0.9rem;
  color: var(--color-ink-soft);
  margin-top: 16px;
}

.article-body {
  padding: 40px 0 64px;
  max-width: 70ch;
}
.article-body h2 { margin-top: 1.8em; font-size: 1.6rem; }
.article-body h3 { margin-top: 1.4em; font-size: 1.2rem; }
.article-body p { font-size: 1.05rem; }
.article-body ul, .article-body ol { color: var(--color-ink-soft); padding-left: 1.4em; }
.article-body li { margin-bottom: 0.5em; }

.callout {
  background: #EEF6FB;
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 28px 0;
  font-family: var(--font-utility);
  font-size: 0.98rem;
  box-shadow: var(--shadow-sm);
}
.callout strong { color: var(--color-ink); }

.article-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 0 64px;
  max-width: 70ch;
  font-family: var(--font-utility);
}
.article-footer a { font-weight: 600; }

/* ============ Pricing / Product cards ============ */

.pricing-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: left;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.pricing-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.pricing-card.featured {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
}
.pricing-card.featured:hover {
  box-shadow: var(--shadow-hover);
}
.pricing-card .price {
  font-family: var(--font-display);
  font-size: 2.4rem;
  font-weight: 700;
  margin: 12px 0 4px;
}
.pricing-card .price-note {
  font-family: var(--font-utility);
  font-size: 0.85rem;
  color: var(--color-ink-soft);
  margin-bottom: 20px;
}
.pricing-card ul {
  list-style: none;
  padding: 0;
  margin: 0 0 24px;
  font-family: var(--font-utility);
  font-size: 0.95rem;
}
.pricing-card li {
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-ink-soft);
  display: flex;
  gap: 10px;
}
.pricing-card li:last-child { border-bottom: none; }
.pricing-card li::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--color-verified);
  margin-top: 8px;
  flex-shrink: 0;
}

.coming-soon-badge {
  display: inline-block;
  font-family: var(--font-utility);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: #FEF3C7;
  color: #92400E;
  padding: 4px 10px;
  border-radius: 4px;
  margin-bottom: 16px;
}

/* ============ Footer ============ */

.site-footer {
  background: var(--color-ink);
  color: #B8C4D1;
  padding: 56px 0 32px;
  font-family: var(--font-utility);
  font-size: 0.92rem;
  margin-top: 40px;
}
.site-footer .footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  padding-bottom: 40px;
  border-bottom: 1px solid #2A3645;
}
@media (max-width: 800px) {
  .site-footer .footer-grid { grid-template-columns: 1fr 1fr; }
}
.site-footer h4 {
  color: #fff;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 14px;
}
.site-footer a { color: #B8C4D1; }
.site-footer a:hover { color: #fff; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 10px; }
.site-footer p { color: #8A99AB; }
.footer-bottom {
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  color: #8A99AB;
  font-size: 0.85rem;
}
.footer-logo { display: flex; align-items: center; gap: 10px; color: #fff; font-family: var(--font-display); font-weight: 700; margin-bottom: 12px; }
.footer-logo img { height: 32px; filter: brightness(0) invert(1); }

/* ============ Legal pages ============ */

.legal-body {
  padding: 48px 0 64px;
  max-width: 70ch;
}
.legal-body h2 { margin-top: 1.6em; font-size: 1.3rem; }
.legal-body p, .legal-body li { font-size: 0.98rem; }
.legal-body .updated {
  font-family: var(--font-utility);
  font-size: 0.85rem;
  color: var(--color-ink-soft);
  margin-bottom: 24px;
}