/* =========================================================
   RELATED BOOKS — section shell
========================================================= */
#related-books.related-books.section {
  background: #dfe6e8;
  background-color: #dfe6e8;
  --background-color: #dfe6e8;
  --surface-color: transparent;
}

/* =========================================================
   RELATED BOOKS — section heading
========================================================= */
#related-books .section-title h2 {
  color: #15485a;
  letter-spacing: -0.02em;
}

#related-books .section-title p {
  max-width: 42rem;
  margin-inline: auto;
  color: #5f737b;
}

/* =========================================================
   RELATED BOOKS — card shell
========================================================= */
#related-books .related-book-card {
  height: 100%;
  overflow: hidden;
  border-radius: 1.35rem;
  background: #c7d5d9;
  box-shadow:
    0 1.1rem 2.5rem rgba(21, 72, 90, 0.08),
    inset 0 0 0 1px rgba(255, 255, 255, 0.32);
  transition:
    transform 0.28s ease,
    box-shadow 0.28s ease,
    background-color 0.28s ease;
}

#related-books .related-book-card:hover {
  transform: translateY(-4px);
  box-shadow:
    0 1.35rem 2.9rem rgba(21, 72, 90, 0.12),
    inset 0 0 0 1px rgba(255, 255, 255, 0.38);
}

/* =========================================================
   RELATED BOOKS — image area
========================================================= */
#related-books .book-image {
  position: relative;
  padding: 1rem 1rem 0;
  background: transparent;
}

#related-books .book-image img {
  display: block;
  margin-inline: auto;
  filter: none;
}

#related-books .book-category {
  position: absolute;
  top: 1rem;
  right: 1rem;
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  background: #2a6f86;
  color: #f4fbfd;
  font-size: 0.9rem;
  line-height: 1;
  box-shadow: 0 0.35rem 0.9rem rgba(42, 111, 134, 0.22);
}

/* =========================================================
   RELATED BOOKS — content area
========================================================= */
#related-books .book-info {
  padding: 1.2rem 1.55rem 1.45rem;
  color: #395a66;
}

#related-books .book-info h3 {
  margin-bottom: 0.8rem;
  color: #15485a;
}

#related-books .book-info p {
  color: #395a66;
  line-height: 1.65;
}

/* =========================================================
   RELATED BOOKS — metadata
========================================================= */
#related-books .book-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
  color: #6b8087;
}

#related-books .book-meta span {
  color: #6b8087;
}

#related-books .book-meta i {
  margin-right: 0.3rem;
  color: #2a6f86;
}

/* =========================================================
   RELATED BOOKS — actions
========================================================= */
#related-books .book-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.2rem;
}

#related-books .btn-details,
#related-books .btn-purchase {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.82rem 1.28rem;
  border-radius: 999px;
  text-decoration: none;
  transition:
    background-color 0.25s ease,
    color 0.25s ease,
    border-color 0.25s ease,
    transform 0.25s ease,
    box-shadow 0.25s ease;
}

#related-books .btn-details {
  border: 1.5px solid rgba(42, 111, 134, 0.72);
  background: rgba(233, 240, 242, 0.62);
  color: #15485a;
}

#related-books .btn-details:hover,
#related-books .btn-details:focus-visible {
  transform: translateY(-1px);
  border-color: #2a6f86;
  background: #2a6f86;
  color: #f4fbfd;
}

#related-books .btn-purchase {
  border: 1.5px solid #2a6f86;
  background: #2a6f86;
  color: #f4fbfd;
  box-shadow: 0 0.5rem 1rem rgba(42, 111, 134, 0.16);
}

#related-books .btn-purchase:hover,
#related-books .btn-purchase:focus-visible {
  transform: translateY(-1px);
  border-color: #1f596d;
  background: #1f596d;
  color: #f4fbfd;
}

/* =========================================================
   RELATED BOOKS — focus polish
========================================================= */
#related-books a:focus-visible {
  outline: 2px solid color-mix(in srgb, #2a6f86, white 25%);
  outline-offset: 3px;
}

/* =========================================================
   RELATED BOOKS — responsive adjustments
========================================================= */
@media (max-width: 767.98px) {
  #related-books .book-info {
    padding: 1.1rem 1.15rem 1.25rem;
  }
}