.nav-link:hover {
  color: #1e40af;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.section-header {
  position: relative;
  padding-bottom: .5rem;
  margin-bottom: 2rem;
  display: inline-block;
}

.section-header::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 50%;
  height: 4px;
  background: #3b82f6;
  border-radius: 9999px;
}

@media (max-width:640px) {
  .nav-menu {
    display: none;
    flex-direction: column;
    background: #fff;
    border-top: 1px solid #e5e7eb;
  }

  .nav-menu.open {
    display: flex;
  }

  .nav-menu a {
    padding: 1rem;
    border-bottom: 1px solid #f3f4f6;
  }
}

.footer-link {
  color: #9ca3af;
  transition: color .15s ease;
}

.footer-link:hover {
  color: #fff;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.breadcrumb a {
  color: #1e40af;
}

.gallery-grid img,
.gallery-grid video {
  border-radius: 1rem;
  width: 100%;
  height: 220px;
  object-fit: cover;
}

.uc-wrapper {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px;
}

.uc-title {
  font-size: 2rem;
  font-weight: 700;
  color: #1e3a8a;
  margin-bottom: 10px;
}

.uc-text {
  font-size: 1rem;
  color: #555;
  max-width: 600px;
}
/* subtle icon hover animation */
  .topic-card .topic-icon {
    transition: transform .22s ease, filter .22s ease;
    will-change: transform;
  }

  .topic-card:hover .topic-icon {
    transform: translateY(-2px) scale(1.06);
    filter: drop-shadow(0 10px 18px rgba(2, 8, 23, .18));
  }

  /* tiny illustration (watermark) in each card */
  .topic-card {
    position: relative;
    overflow: hidden;
  }

  .topic-card .topic-illus {
    position: absolute;
    right: 14px;
    bottom: 14px;
    width: 72px;
    height: 72px;
    opacity: .14;
    pointer-events: none;
    transition: transform .25s ease, opacity .25s ease;
  }

  .topic-card:hover .topic-illus {
    transform: rotate(-4deg) scale(1.05);
    opacity: .18;
  }

  @media (max-width: 640px) {
    .topic-card .topic-illus {
      width: 62px;
      height: 62px;
      right: 12px;
      bottom: 12px;
    }
  }