/* APAI public landing — complements base.css */

.landing {
  --landing-ink: #0f172a;
  --landing-muted: #475569;
  --landing-panel: #f1f5f9;
  --landing-accent: #1d4ed8;
  --landing-glow: #93c5fd;
  color: var(--landing-ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(147, 197, 253, 0.45), transparent 55%),
    radial-gradient(900px 420px at 90% 0%, rgba(191, 219, 254, 0.35), transparent 50%),
    linear-gradient(180deg, #f8fafc 0%, #ffffff 42%, #f1f5f9 100%);
  min-height: 100vh;
}

.landing a:focus-visible,
.landing button:focus-visible {
  outline: 2px solid var(--landing-accent);
  outline-offset: 3px;
}

.landing-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 1040px;
  margin: 0 auto;
  padding: 1.1rem 1.25rem;
}

.landing-brand {
  font-family: "Source Serif 4", "Noto Serif TC", "Songti TC", Georgia, serif;
  font-size: 1.65rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--landing-ink);
  text-decoration: none;
}

.landing-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
  align-items: center;
}

.landing-nav a {
  color: var(--landing-muted);
  text-decoration: none;
  font-size: 0.95rem;
}

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

.landing-hero {
  max-width: 1040px;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 3rem;
  display: grid;
  gap: 1.25rem;
}

.landing-hero__brand {
  margin: 0;
  font-family: "Source Serif 4", "Noto Serif TC", "Songti TC", Georgia, serif;
  font-size: clamp(2.6rem, 6vw, 4.2rem);
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1.05;
}

.landing-hero__tagline {
  margin: 0;
  max-width: 34rem;
  font-size: clamp(1.15rem, 2.4vw, 1.45rem);
  font-weight: 600;
  line-height: 1.35;
  color: #1e293b;
}

.landing-hero__lead {
  margin: 0;
  max-width: 36rem;
  font-size: 1.05rem;
  line-height: 1.65;
  color: var(--landing-muted);
}

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

.landing-cta .btn {
  border-radius: 999px;
  padding: 0.7rem 1.35rem;
  font-weight: 600;
}

.landing-cta .btn-secondary {
  background: #fff;
}

.landing-section {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
}

.landing-section h2 {
  margin: 0 0 0.75rem;
  font-size: 1.5rem;
}

.landing-section > p {
  margin: 0 0 1.25rem;
  max-width: 40rem;
  color: var(--landing-muted);
}

.landing-features {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.landing-features li {
  background: rgba(255, 255, 255, 0.85);
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  padding: 1.1rem 1.15rem;
}

.landing-features h3 {
  margin: 0 0 0.45rem;
  font-size: 1.05rem;
}

.landing-features p {
  margin: 0;
  color: var(--landing-muted);
  font-size: 0.95rem;
  line-height: 1.55;
}

.landing-faq details {
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 0.85rem 1rem;
  margin-bottom: 0.65rem;
}

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

.landing-faq p {
  margin: 0.65rem 0 0;
  color: var(--landing-muted);
  line-height: 1.6;
}

.landing-footer {
  border-top: 1px solid #e2e8f0;
  padding: 1.5rem 1.25rem 2.5rem;
  text-align: center;
  color: var(--landing-muted);
  font-size: 0.9rem;
}

.landing-footer nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem 1.1rem;
  margin-bottom: 0.75rem;
}

.landing-footer a {
  color: var(--landing-muted);
}

@media (max-width: 800px) {
  .landing-features {
    grid-template-columns: 1fr;
  }

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