:root {
  --book-ink: #211c1a;
  --book-muted: #706762;
  --book-paper: #f7efe3;
  --book-paper-light: #fcfaf6;
  --book-red: #a91b16;
  --book-red-dark: #74130f;
  --book-gold: #d9ad65;
  --book-line: rgba(33, 28, 26, 0.13);
}

.book-detail-page {
  color: var(--book-ink);
  background: var(--book-paper-light);
}

.book-detail-page h1,
.book-detail-page h2,
.book-detail-page h3 {
  font-family: Georgia, "Times New Roman", serif;
}

.book-detail-intro,
.book-detail-section {
  padding: clamp(3.25rem, 7vw, 6rem) 0;
}

.book-detail-intro {
  background:
    linear-gradient(rgba(33, 28, 26, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(33, 28, 26, 0.025) 1px, transparent 1px),
    var(--book-paper);
  background-size: 30px 30px;
}

.book-detail-panel,
.book-detail-copy,
.book-detail-dark-card,
.book-detail-reader,
.book-detail-review,
.book-detail-video {
  border: 1px solid var(--book-line);
  border-radius: 1.2rem;
  box-shadow: 0 16px 40px rgba(45, 31, 27, 0.09);
}

.book-detail-panel {
  position: sticky;
  top: 4.5rem;
  padding: 1rem 1.15rem;
  color: #fff;
  text-align: center;
  background: linear-gradient(150deg, #14110f, #2e1714);
}

/* El mockup de los microensayos acompaña al contenido sin quedar anclado. */
.book-detail-panel.book-detail-panel--static {
  position: static;
  top: auto;
}

.book-detail-cover {
  display: block;
  width: auto;
  max-width: 100%;
  max-height: min(430px, 50vh);
  margin: 0 auto;
  object-fit: contain;
  filter: drop-shadow(0 18px 22px rgba(0, 0, 0, 0.38));
}

.book-detail-copy {
  height: 100%;
  padding: clamp(1.6rem, 4vw, 3rem);
  background: rgba(255, 255, 255, 0.93);
}

.book-detail-copy h1 {
  margin-bottom: 1.35rem;
  font-size: clamp(2rem, 4.5vw, 3.55rem);
  line-height: 1.05;
}

.book-detail-copy p {
  color: #4f4743;
  font-size: 1.04rem;
  line-height: 1.82;
}

.book-detail-label {
  margin-bottom: 0.7rem;
  color: var(--book-red);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.book-detail-subheading {
  display: flex;
  gap: 0.6rem;
  align-items: center;
  margin: 2.1rem 0 1rem;
  color: var(--book-red-dark);
  font-size: clamp(1.35rem, 2.5vw, 1.8rem);
}

.book-detail-subheading::before {
  width: 2rem;
  height: 3px;
  content: "";
  background: var(--book-red);
  border-radius: 999px;
}

.book-detail-highlight,
.book-detail-quote {
  padding: 1rem 1.15rem;
  color: var(--book-ink) !important;
  background: #fff8ee;
  border-left: 5px solid var(--book-gold);
  border-radius: 0 0.7rem 0.7rem 0;
}

.book-detail-quote {
  margin: 2rem 0 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  font-style: italic;
  line-height: 1.6;
  border-left-color: var(--book-red);
}

.book-detail-question {
  padding: 1.15rem 1.25rem;
  color: #fff !important;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.12rem, 2vw, 1.32rem) !important;
  background: linear-gradient(135deg, #2a1815, #681914);
  border-radius: 0.8rem;
}

.book-detail-features {
  display: grid;
  gap: 0.75rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

.book-detail-features li {
  padding: 0.78rem 0.9rem;
  color: #4b433f;
  background: #fbf5ec;
  border: 1px solid rgba(169, 27, 22, 0.08);
  border-radius: 0.65rem;
}

.book-detail-button {
  display: inline-flex;
  gap: 0.55rem;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.72rem 1.1rem;
  color: #fff;
  font-weight: 800;
  text-decoration: none;
  background: var(--book-red);
  border: 1px solid #c44840;
  border-radius: 0.58rem;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.book-detail-button:hover,
.book-detail-button:focus {
  color: var(--book-ink);
  background: #fff4e5;
  transform: translateY(-2px);
}

.book-detail-availability {
  margin: 0.55rem 0 0;
  color: rgba(255, 255, 255, 0.68);
  font-size: 0.88rem;
}

.book-detail-mid-cta {
  max-width: 820px;
  margin: clamp(2.5rem, 5vw, 4rem) auto 0;
  padding: clamp(1.5rem, 4vw, 2.4rem);
  text-align: center;
  background: rgba(255, 255, 255, 0.93);
  border: 1px solid var(--book-line);
  border-radius: 1.2rem;
  box-shadow: 0 15px 36px rgba(45, 31, 27, 0.08);
}

.book-detail-heading {
  margin-bottom: clamp(2rem, 4vw, 3.25rem);
  font-size: clamp(2rem, 4vw, 3.1rem);
  text-align: center;
}

.book-detail-videos {
  color: #fff;
  background: #1a1311;
}

.book-detail-video {
  max-width: 410px;
  padding: 0.7rem;
  margin: 0 auto;
  overflow: hidden;
  background: #0b0908;
  border-color: rgba(255, 255, 255, 0.12);
}

.book-detail-video iframe { border: 0; }

.book-detail-readers { background: var(--book-paper); }

.book-detail-reader {
  height: 100%;
  padding: 1.7rem;
  background: rgba(255, 255, 255, 0.9);
}

.book-detail-reader p {
  margin: 0;
  color: #4e4541;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.08rem;
  font-style: italic;
  line-height: 1.7;
}

.book-detail-reviews { background: var(--book-paper-light); }
.book-detail-review-grid { display: grid; gap: 1.1rem; }

.book-detail-review {
  padding: clamp(1.4rem, 3vw, 2rem);
  background: #fff;
  border-left: 5px solid var(--book-red);
}

.book-detail-review h3 { font-size: 1.3rem; }
.book-detail-review p { color: #514944; line-height: 1.72; }
.book-detail-stars { color: #c68e2c; letter-spacing: 0.08em; }

.book-detail-final {
  padding: clamp(3.5rem, 7vw, 6rem) 1rem;
  color: #fff;
  text-align: center;
  background: linear-gradient(125deg, #151110, #351513 58%, #74130f);
}

.book-detail-final h2 {
  max-width: 920px;
  margin: 0 auto 1rem;
  font-size: clamp(2rem, 4.5vw, 3.7rem);
}

.book-detail-final .book-detail-button {
  margin-top: 1.4rem;
  color: #351311;
  background: #f4d39f;
  border-color: #f4d39f;
}

.book-detail-side {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  height: 100%;
}

.book-detail-dark-card {
  flex: 1;
  padding: clamp(1.6rem, 4vw, 2.35rem);
  color: #fff;
  background: linear-gradient(145deg, #2a1815, #6a1915);
}

.book-detail-dark-card p { color: rgba(255,255,255,.78); line-height: 1.7; }
.book-detail-dark-card .book-detail-label { color: #f3ca8b; }

@media (max-width: 991.98px) {
  .book-detail-panel { position: static; }
  .book-detail-cover { max-height: 560px; }
}

@media (max-width: 575.98px) {
  .book-detail-intro,
  .book-detail-section { padding: 2.6rem 0; }
  .book-detail-panel,
  .book-detail-copy,
  .book-detail-dark-card { padding: 1.3rem; }
  .book-detail-button { width: 100%; }
}