/* ====== BOOK DETAIL ====== */
.book-detail {
    padding: 2.5rem 0 4rem;
}

.book-breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}
.book-breadcrumb a {
    color: var(--gold-light);
    text-decoration: none;
}
.book-breadcrumb a:hover { color: var(--gold-primary); }
.book-breadcrumb .sep { color: var(--text-muted); }

.book-detail-grid {
    display: grid;
    grid-template-columns: 320px 1fr;
    gap: 3rem;
    align-items: start;
}

.book-cover-col {
    position: sticky;
    top: 100px;
}

.book-cover-frame {
    position: relative;
    border-radius: 16px;
    padding: 1rem;
    background: linear-gradient(160deg, rgba(240,184,51,0.12), rgba(255,255,255,0.04));
    border: 1px solid var(--glass-border);
    box-shadow: 0 30px 60px -30px rgba(0,0,0,0.8);
}
.book-cover-img {
    width: 100%;
    border-radius: 10px;
    aspect-ratio: 2/3;
    object-fit: cover;
    display: block;
}
.book-featured-badge {
    position: absolute;
    top: 1.4rem;
    left: 1.4rem;
    background: var(--gradient-gold);
    color: #1a1206;
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    padding: 0.3rem 0.7rem;
    border-radius: 20px;
    text-transform: uppercase;
}

.book-actions {
    display: flex;
    flex-direction: column;
    gap: 0.7rem;
    margin-top: 1.2rem;
}
.btn-book-primary, .btn-book-secondary, .btn-book-ghost {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.85rem 1rem;
    border-radius: 12px;
    font-weight: 700;
    font-size: 0.9rem;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition-smooth);
    border: 1px solid transparent;
    width: 100%;
}
.btn-book-primary {
    background: var(--gradient-gold);
    color: #1a1206;
}
.btn-book-primary:hover {
    filter: brightness(1.08);
    transform: translateY(-2px);
    color: #1a1206;
}
.btn-book-secondary {
    background: rgba(255,255,255,0.06);
    color: var(--text-primary);
    border-color: var(--glass-border);
}
.btn-book-secondary:hover {
    background: rgba(255,255,255,0.12);
    color: var(--text-primary);
}
.btn-book-ghost {
    background: transparent;
    color: var(--text-secondary);
    border-color: var(--glass-border);
}
.btn-book-ghost:hover, .btn-book-ghost.saved {
    color: var(--gold-primary);
    border-color: var(--gold-primary);
}

.book-file-info {
    margin-top: 1.2rem;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 1rem;
}
.book-file-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    padding: 0.4rem 0;
    color: var(--text-secondary);
    border-bottom: 1px solid rgba(255,255,255,0.04);
}
.book-file-row:last-child { border-bottom: none; }
.book-file-row i { color: var(--gold-primary); margin-right: 0.4rem; }

.book-kicker {
    color: var(--gold-primary);
    font-family: var(--font-grotesk);
    text-transform: uppercase;
    letter-spacing: 0.18em;
    font-size: 0.78rem;
    font-weight: 600;
}
.book-title {
    font-family: var(--font-display);
    font-size: clamp(1.9rem, 4vw, 3rem);
    line-height: 1.1;
    margin: 0.4rem 0 0.5rem;
}
.book-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: 0.8rem;
}
.book-author {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 1.2rem;
}
.book-author strong { color: var(--gold-light); }

.book-price-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}
.book-price {
    font-size: 1.8rem;
    font-weight: 800;
    font-family: var(--font-grotesk);
    color: var(--gold-primary);
}
.book-price.free { color: #4ade80; }
.book-format-pill {
    font-size: 0.75rem;
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    background: rgba(255,255,255,0.06);
    border: 1px solid var(--glass-border);
    color: var(--text-secondary);
}

.book-description {
    font-size: 1.02rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 1.8rem;
}
.book-description p { margin-bottom: 0.8rem; }

.book-meta-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: 0.8rem;
    margin-bottom: 1.8rem;
}
.book-meta-item {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 0.8rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}
.book-meta-label {
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
}
.book-meta-value {
    font-weight: 700;
    font-size: 0.95rem;
}

.book-about-author, .book-toc {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--glass-border);
}
.book-about-author h3, .book-toc h3 {
    font-size: 1.1rem;
    margin-bottom: 0.8rem;
    color: var(--gold-light);
}
.book-about-author h3 i, .book-toc h3 i { margin-right: 0.4rem; }
.book-about-author p { color: var(--text-secondary); line-height: 1.8; }
.book-toc ul { list-style: none; padding: 0; margin: 0; }
.book-toc li {
    padding: 0.4rem 0;
    color: var(--text-secondary);
    border-bottom: 1px dashed rgba(255,255,255,0.06);
}

.book-related {
    margin-top: 4rem;
}
.book-related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 1.2rem;
    margin-top: 1.5rem;
}
.book-related-card {
    text-decoration: none;
    color: var(--text-primary);
}
.book-related-cover {
    aspect-ratio: 2/3;
    border-radius: 10px;
    background-size: cover;
    background-position: center;
    border: 1px solid var(--glass-border);
    transition: var(--transition-smooth);
}
.book-related-card:hover .book-related-cover {
    transform: translateY(-4px);
    border-color: var(--gold-primary);
}
.book-related-card h4 {
    font-size: 0.92rem;
    margin: 0.6rem 0 0.2rem;
}
.book-related-card span {
    font-size: 0.78rem;
    color: var(--text-muted);
}

@media (max-width: 860px) {
    .book-detail-grid { grid-template-columns: 1fr; gap: 2rem; }
    .book-cover-col { position: static; }
    .book-cover-frame { max-width: 280px; margin: 0 auto; }
}