:root {
  --primary-color: #1a2530;
  --accent-color: #c5a880;
  --text-dark: #333333;
  --text-light: #666666;
  --bg-light: #f8f9fa;
  --white: #ffffff;
}

body {
  font-family: "Georgia", serif;
  margin: 0;
  padding: 0;
  color: var(--text-dark);
  line-height: 1.6;
  background-color: var(--white);
}

.book-detail-container {
  padding: 50px 0;
  display: grid;
  grid-template-columns: 4fr 8fr;
  gap: 50px;
}

.book-sidebar {
  position: sticky;
  top: 115px;
  align-self: start;
  text-align: center;
}
.page-hero::after {
    background: linear-gradient(180deg, rgb(11 25 44 / 43%) 0%, rgb(11 25 44 / 52%) 70%, var(--navy) 100%);
}
.book-cover-wrapper {
  background: var(--bg-light);
  border-radius: 4px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
  margin-bottom: 25px;
}
.book-cover-wrapper img {
  width: 100%;
}
.book-cover-img {
  max-width: 100%;
  height: auto;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
  border-radius: 2px;
  transition: transform 0.3s ease;
}

.book-cover-img:hover {
  transform: scale(1.02);
}

.purchase-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.btn {
  font-family: sans-serif;
  display: inline-block;
  padding: 14px 20px;
  font-weight: 600;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.3s ease;
  text-align: center;
}

.btn-primary {
  background-color: var(--primary-color);
  color: var(--white);
  border: 1px solid var(--primary-color);
}

.btn-primary:hover {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
}

.btn-secondary {
  background-color: transparent;
  color: var(--primary-color);
  border: 1px solid #cbd5e1;
}

.btn-secondary:hover {
  background-color: var(--bg-light);
  border-color: var(--primary-color);
}

/* Right Side: Content Area */
.book-main-content h2 {
  font-size: 1.8rem;
  color: var(--primary-color);
  margin-top: 0;
  margin-bottom: 20px;
  font-weight: 400;
  border-bottom: 1px solid #e2e8f0;
  padding-bottom: 10px;
}

.book-meta {
  font-family: sans-serif;
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 25px;
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.book-meta span i {
  color: var(--accent-color);
  margin-right: 6px;
}

.book-description {
  font-size: 1.1rem;
  color: #4a5568;
  margin-bottom: 40px;
  text-align: justify;
}


.endorsements-section {
  margin-top: 40px;
}

.review-card {
  background-color: var(--bg-light);
  border-left: 3px solid var(--accent-color);
  padding: 25px;
  margin-bottom: 20px;
  border-radius: 0 4px 4px 0;
}

.review-text {
  font-style: italic;
  font-size: 1.05rem;
  color: var(--text-dark);
  margin: 0 0 15px 0;
}

.review-author {
  font-family: sans-serif;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary-color);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.review-author span {
  font-weight: 400;
  color: var(--text-light);
  text-transform: none;
  letter-spacing: 0;
}

/* Responsive Breakpoints */
@media (max-width: 992px) {
  .book-detail-container {
    padding: 20px 0;
}
  .book-detail-container {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .book-cover-wrapper {
    margin-bottom: 10px;
}
.endorsements-section {
    margin-top: 0;
}
  .book-sidebar {
    position: relative;
    top: 0;
    max-width: 400px;
    margin: 0 auto;
    width: 100%;
  }
}

.flip {
  position: relative;
  width: 100%;
}

.flip > .front,
.flip > .back {
  display: block;
  transition-timing-function: cubic-bezier(0.175, 0.885, 0.32, 1.275);
  transition-duration: 0.5s;
  transition-property: transform, opacity;
}

.flip > .front {
  transform: rotateY(0deg);
}

.flip > .back {
  position: absolute;
  opacity: 0;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transform: rotateY(-180deg);
}

.flip:hover > .front {
  transform: rotateY(180deg);
}

.flip:hover > .back {
  opacity: 1;
  transform: rotateY(0deg);
}

/* Vertical Flip */

.flip.flip-vertical > .back {
  transform: rotateX(-180deg);
}

.flip.flip-vertical:hover > .front {
  transform: rotateX(180deg);
}

.flip.flip-vertical:hover > .back {
  transform: rotateX(0deg);
}

/* Custom */

.flip {
  position: relative;
  display: inline-block;
  perspective: 1000px;
}

.flip > .front,
.flip > .back {
  display: block;
  color: #fff;
  width: inherit;
  background-size: cover !important;
  background-position: center !important;
  height: auto;
}