:root {
  --bks-ink: #0f1f2e;
  --bks-ink-soft: #3a4f63;
  --bks-paper: #f3f6f4;
  --bks-paper-2: #e7eee9;
  --bks-accent: #0d6e5a;
  --bks-accent-deep: #085445;
  --bks-highlight: #d4a24c;
  --bks-line: rgba(15, 31, 46, 0.12);
  --bks-radius: 0.75rem;
  --font-display: "Fraunces", Georgia, serif;
  --font-body: "Be Vietnam Pro", "Segoe UI", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--bks-ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(13, 110, 90, 0.16), transparent 60%),
    radial-gradient(900px 400px at 100% 0%, rgba(212, 162, 76, 0.18), transparent 55%),
    linear-gradient(180deg, var(--bks-paper) 0%, #f8faf9 45%, var(--bks-paper-2) 100%);
  line-height: 1.6;
}

a {
  color: var(--bks-accent-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.15em;
}

a:hover {
  color: var(--bks-accent);
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 68rem;
  margin: 0 auto;
  padding: 1.25rem 1.25rem 0.5rem;
}

.brand {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--bks-ink);
  text-decoration: none;
}

.brand span {
  color: var(--bks-accent);
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  font-size: 0.9375rem;
}

.nav a {
  color: var(--bks-ink-soft);
  text-decoration: none;
  font-weight: 500;
}

.nav a:hover {
  color: var(--bks-accent-deep);
}

.hero {
  max-width: 68rem;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 2rem;
  display: grid;
  gap: 1.5rem;
}

.hero h1 {
  margin: 0;
  max-width: 18ch;
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 5vw, 3.4rem);
  line-height: 1.12;
  letter-spacing: -0.03em;
}

.hero .lead {
  margin: 0;
  max-width: 40rem;
  font-size: 1.125rem;
  color: var(--bks-ink-soft);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.75rem;
  padding: 0.65rem 1.25rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9375rem;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform 0.18s ease, background 0.18s ease, box-shadow 0.18s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--bks-accent);
  color: #fff;
  box-shadow: 0 10px 24px rgba(13, 110, 90, 0.25);
}

.btn-primary:hover {
  background: var(--bks-accent-deep);
  color: #fff;
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.55);
  border-color: var(--bks-line);
  color: var(--bks-ink);
}

.section {
  max-width: 68rem;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 2.5rem;
}

.section h2 {
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2rem);
  letter-spacing: -0.02em;
}

.section p,
.section li {
  color: var(--bks-ink-soft);
}

.section ul {
  padding-left: 1.2rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 1rem;
  margin-top: 1.25rem;
}

.feature {
  padding: 1.1rem 1.15rem;
  border: 1px solid var(--bks-line);
  border-radius: var(--bks-radius);
  background: rgba(255, 255, 255, 0.55);
}

.feature h3 {
  margin: 0 0 0.4rem;
  font-size: 1.05rem;
}

.feature p {
  margin: 0;
  font-size: 0.9375rem;
}

.prose {
  max-width: 42rem;
}

.prose h2 {
  margin-top: 2rem;
}

.prose h3 {
  margin-top: 1.5rem;
  font-size: 1.125rem;
}

.faq details {
  margin: 0.65rem 0;
  padding: 0.85rem 1rem;
  border: 1px solid var(--bks-line);
  border-radius: var(--bks-radius);
  background: rgba(255, 255, 255, 0.6);
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
}

.site-footer {
  max-width: 68rem;
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
  border-top: 1px solid var(--bks-line);
  color: var(--bks-ink-soft);
  font-size: 0.875rem;
}

.site-footer .brand-foot {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--bks-ink);
  margin-bottom: 0.5rem;
}

.highlight {
  color: var(--bks-highlight);
}

@media (max-width: 640px) {
  .site-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero {
    padding-top: 1.5rem;
  }
}