/* Neiht Piano — /gioi-thieu.html */
.nab-page-bg {
  font-family: 'Plus Jakarta Sans', system-ui, sans-serif;
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(59, 130, 246, 0.1), transparent),
    linear-gradient(180deg, #f8fafc 0%, #fff 40%, #f1f5f9 100%);
}

.nab-hero {
  margin-bottom: 1.5rem;
  border-radius: 1.35rem;
  border: 1px solid #e2e8f0;
  background: #fff;
  padding: 1.5rem 1.25rem;
  box-shadow: 0 20px 50px -24px rgba(15, 23, 42, 0.12);
}

@media (min-width: 640px) {
  .nab-hero {
    padding: 2rem 2rem 1.75rem;
    border-radius: 1.75rem;
  }
}

.nab-hero h1 {
  font-size: 1.65rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #0f172a;
}

@media (min-width: 640px) {
  .nab-hero h1 {
    font-size: 2.1rem;
  }
}

.nab-hero p {
  margin-top: 0.65rem;
  font-size: 0.9rem;
  line-height: 1.6;
  color: #64748b;
}

.nab-grid {
  display: grid;
  gap: 1rem;
}

@media (min-width: 768px) {
  .nab-grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
  }
}

.nab-card {
  border-radius: 1rem;
  border: 1px solid #e2e8f0;
  background: #fff;
  padding: 1.15rem 1.2rem;
  box-shadow: 0 4px 18px rgba(15, 23, 42, 0.04);
}

.nab-card h2 {
  font-size: 1rem;
  font-weight: 800;
  color: #0f172a;
}

.nab-card p,
.nab-card li {
  margin-top: 0.5rem;
  font-size: 0.875rem;
  line-height: 1.65;
  color: #475569;
}

.nab-card ul {
  margin-top: 0.5rem;
  padding-left: 1.15rem;
}

.nab-faq {
  margin-top: 1.25rem;
}

.nab-faq details {
  border-radius: 0.85rem;
  border: 1px solid #e2e8f0;
  background: #fff;
  margin-bottom: 0.5rem;
  overflow: hidden;
}

.nab-faq summary {
  cursor: pointer;
  padding: 0.85rem 1rem;
  font-size: 0.9rem;
  font-weight: 700;
  color: #0f172a;
  list-style: none;
}

.nab-faq summary::-webkit-details-marker {
  display: none;
}

.nab-faq details[open] summary {
  border-bottom: 1px solid #f1f5f9;
  background: #f8fafc;
}

.nab-faq details p {
  padding: 0.85rem 1rem 1rem;
  font-size: 0.875rem;
  line-height: 1.65;
  color: #475569;
}

.nab-cta {
  margin-top: 1.25rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.nab-cta a {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  border-radius: 9999px;
  padding: 0.55rem 1rem;
  font-size: 0.8125rem;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
}

.nab-cta-primary {
  background: #2563eb;
  color: #fff;
}

.nab-cta-primary:hover {
  background: #1d4ed8;
}

.nab-cta-secondary {
  border: 1px solid #e2e8f0;
  background: #fff;
  color: #334155;
}

.nab-cta-secondary:hover {
  background: #f8fafc;
}