:root {
  --color-bg: #ffffff;
  --color-surface: #f5f8fc;
  --color-surface-2: #eaf1f9;
  --color-text: #0f1d2e;
  --color-text-muted: #4a5b71;
  --color-primary: #1a4a8a;
  --color-primary-dark: #123764;
  --color-primary-light: #3a6cb0;
  --color-accent: #f0c419;
  --color-border: #d8e3f0;
  --radius: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px rgba(15, 29, 46, 0.06);
  --shadow-md: 0 4px 16px rgba(15, 29, 46, 0.08);
  --container: 1120px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: Georgia, "Times New Roman", serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; display: block; }
a { color: var(--color-primary); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { color: var(--color-primary-dark); }

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

/* Header */
.site-header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(180%) blur(8px);
  background: rgba(255, 255, 255, 0.92);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-top: 16px;
  padding-bottom: 16px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.01em;
}
.brand-mark {
  width: 32px; height: 32px; border-radius: 8px;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  display: inline-flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 800; font-size: 15px;
}
.nav { display: flex; gap: 28px; align-items: center; }
.nav a { color: var(--color-text-muted); text-decoration: none; font-weight: 500; font-size: 15px; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--color-primary); }
.nav-toggle { display: none; }

@media (max-width: 760px) {
  .nav { display: none; }
  .nav.open { display: flex; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0; background: #fff; padding: 16px 24px; gap: 14px; border-bottom: 1px solid var(--color-border); }
  .nav-toggle { display: inline-flex; background: none; border: 1px solid var(--color-border); border-radius: 8px; padding: 8px 12px; font: inherit; cursor: pointer; }
}

/* Hero */
.hero {
  padding: 72px 0 56px;
  background: radial-gradient(ellipse at top left, var(--color-surface-2) 0%, var(--color-surface) 50%, var(--color-bg) 100%);
}
.hero-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 56px; align-items: center; }
.hero-eyebrow { display: inline-block; background: rgba(26, 74, 138, 0.08); color: var(--color-primary); padding: 6px 12px; border-radius: 999px; font-size: 13px; font-weight: 600; letter-spacing: 0.02em; margin-bottom: 18px; }
.hero h1 { font-size: clamp(32px, 4.5vw, 46px); line-height: 1.15; margin: 0 0 20px; letter-spacing: -0.02em; font-weight: 800; }
.hero p.lead { font-size: 19px; color: var(--color-text-muted); margin: 0 0 28px; max-width: 56ch; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 13px 22px; border-radius: var(--radius); font-weight: 600; font-size: 16px;
  text-decoration: none; transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
  cursor: pointer; border: none;
}
.btn-primary { background: var(--color-primary); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: var(--color-primary-dark); color: #fff; box-shadow: var(--shadow-md); transform: translateY(-1px); }
.btn-secondary { background: #fff; color: var(--color-primary); border: 1px solid var(--color-border); }
.btn-secondary:hover { background: var(--color-surface); color: var(--color-primary-dark); }

.hero-card {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  padding: 28px; box-shadow: var(--shadow-md);
}
.hero-card h2 { margin: 0 0 14px; font-size: 18px; }
.hero-card ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 12px; }
.hero-card li { display: flex; gap: 12px; align-items: flex-start; font-size: 15px; color: var(--color-text-muted); }
.hero-card li::before {
  content: ""; flex: 0 0 22px; height: 22px; border-radius: 50%;
  background: var(--color-primary); color: #fff;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='white'><path d='M9 16.2l-3.5-3.5-1.4 1.4L9 19l11-11-1.4-1.4z'/></svg>");
  background-size: 16px; background-position: center; background-repeat: no-repeat;
}

@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero { padding: 48px 0 40px; }
}

/* Sections */
section.block { padding: 64px 0; }
section.block.alt { background: var(--color-surface); }
section.block h2 { font-size: clamp(24px, 3vw, 32px); margin: 0 0 16px; letter-spacing: -0.01em; line-height: 1.25; font-weight: 700; }
section.block .lead { font-size: 18px; color: var(--color-text-muted); max-width: 70ch; margin: 0 0 24px; }
section.block p { margin: 0 0 16px; }
.prose { max-width: 72ch; }
.prose h2 { margin-top: 48px; }
.prose h2:first-child { margin-top: 0; }
.prose ul { padding-left: 22px; }
.prose ul li { margin-bottom: 8px; }

/* Feature grid */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 8px; }
.feature {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius-lg);
  padding: 24px; transition: border-color .15s ease, transform .15s ease;
}
.feature:hover { border-color: var(--color-primary-light); transform: translateY(-2px); }
.feature .icon {
  width: 40px; height: 40px; border-radius: 10px;
  background: var(--color-surface-2); color: var(--color-primary);
  display: inline-flex; align-items: center; justify-content: center; margin-bottom: 14px;
  font-size: 20px; font-weight: 700;
}
.feature h3 { margin: 0 0 8px; font-size: 17px; }
.feature p { margin: 0; color: var(--color-text-muted); font-size: 15px; }
@media (max-width: 760px) { .features { grid-template-columns: 1fr; } }

/* CTA banner */
.cta-banner {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: #fff; border-radius: var(--radius-lg); padding: 40px;
  display: flex; gap: 28px; align-items: center; justify-content: space-between; flex-wrap: wrap;
}
.cta-banner h2 { margin: 0 0 6px; font-size: 24px; color: #fff; font-weight: 700; }
.cta-banner p { margin: 0; opacity: 0.9; max-width: 60ch; }
.cta-banner .btn-primary { background: #fff; color: var(--color-primary-dark); }
.cta-banner .btn-primary:hover { background: var(--color-accent); color: var(--color-primary-dark); }

/* FAQ */
.faq { display: grid; gap: 12px; max-width: 800px; }
.faq details {
  background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius);
  padding: 18px 22px;
}
.faq summary {
  font-weight: 600; cursor: pointer; list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; font-size: 22px; color: var(--color-primary); font-weight: 400; transition: transform .2s ease;
}
.faq details[open] summary::after { content: "−"; }
.faq details[open] { border-color: var(--color-primary-light); }
.faq p { margin: 12px 0 0; color: var(--color-text-muted); }

/* Breadcrumb */
.crumbs { padding: 18px 0 0; font-size: 14px; color: var(--color-text-muted); }
.crumbs ol { list-style: none; padding: 0; margin: 0; display: flex; gap: 8px; flex-wrap: wrap; }
.crumbs li:not(:first-child)::before { content: "›"; margin-right: 8px; color: var(--color-text-muted); }
.crumbs a { color: var(--color-text-muted); text-decoration: none; }
.crumbs a:hover { color: var(--color-primary); }

/* Page header for subpages */
.page-header { padding: 48px 0 24px; background: var(--color-surface); border-bottom: 1px solid var(--color-border); }
.page-header h1 { font-size: clamp(28px, 4vw, 40px); margin: 12px 0 12px; letter-spacing: -0.02em; line-height: 1.2; }
.page-header .lead { font-size: 18px; color: var(--color-text-muted); max-width: 70ch; margin: 0; }

/* Internal links section */
.related { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.related a {
  display: block; background: #fff; border: 1px solid var(--color-border); border-radius: var(--radius);
  padding: 20px; text-decoration: none; color: var(--color-text); transition: all .15s ease;
}
.related a:hover { border-color: var(--color-primary); box-shadow: var(--shadow-md); transform: translateY(-2px); }
.related a strong { display: block; font-size: 16px; margin-bottom: 4px; color: var(--color-primary); }
.related a span { color: var(--color-text-muted); font-size: 14px; }
@media (max-width: 660px) { .related { grid-template-columns: 1fr; } }

/* Footer */
.site-footer {
  background: var(--color-text); color: rgba(255,255,255,0.75);
  padding: 48px 0 24px; margin-top: 64px; font-size: 14px;
}
.site-footer .container { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; }
.site-footer h3 { color: #fff; font-size: 14px; text-transform: uppercase; letter-spacing: 0.06em; margin: 0 0 14px; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.site-footer a { color: rgba(255,255,255,0.75); text-decoration: none; }
.site-footer a:hover { color: #fff; }
.site-footer .brand { color: #fff; }
.site-footer .copyright { border-top: 1px solid rgba(255,255,255,0.12); margin-top: 32px; padding-top: 20px; font-size: 13px; opacity: 0.7; }
@media (max-width: 760px) { .site-footer .container { grid-template-columns: 1fr; } }