.book-page { background: linear-gradient(180deg, #f4efe6 0, #f8f5ee 390px, #f8f5ee 100%); }
.book-breadcrumb { display: flex; flex-wrap: wrap; gap: 8px; margin: -18px 0 24px; color: var(--muted); font-size: 13px; }
.book-breadcrumb a:hover { color: var(--brand); }
.book-breadcrumb strong { color: var(--ink); }
.book-hero { display: grid; grid-template-columns: 230px minmax(0, 1fr); gap: 52px; align-items: center; min-height: 360px; padding: 44px 54px; color: #fff; background: radial-gradient(circle at 85% 12%, rgba(216,174,100,.24), transparent 34%), linear-gradient(120deg, #14231f, #31594d 62%, #1b312b); box-shadow: 0 28px 70px rgba(27,42,37,.16); }
.book-hero__cover { width: 210px; aspect-ratio: 3 / 4; overflow: hidden; background: #e9dfce; border: 8px solid rgba(255,255,255,.78); box-shadow: 0 20px 42px rgba(0,0,0,.32); transform: rotate(-1.5deg); }
.book-hero__cover a, .book-hero__cover img { display: block; width: 100%; height: 100%; }
.book-hero__cover img { object-fit: cover; }
.book-tags { display: flex; gap: 8px; margin-bottom: 14px; }
.book-tags span, .book-tags a { padding: 5px 10px; color: #f2dbad; border: 1px solid rgba(242,219,173,.34); font-size: 12px; }
.book-tags a:hover { color: #fff; border-color: rgba(255,255,255,.72); }
.book-hero h1 { margin: 0; font: 700 clamp(36px, 5vw, 58px)/1.12 var(--serif); letter-spacing: .04em; }
.book-byline { margin: 12px 0 0; color: rgba(255,255,255,.72); }
.book-byline a { color: #f2dbad; }
.book-intro { display: -webkit-box; max-width: 720px; margin: 20px 0 0; overflow: hidden; color: rgba(255,255,255,.76); line-height: 1.85; -webkit-box-orient: vertical; -webkit-line-clamp: 3; }
.book-stats { display: flex; flex-wrap: wrap; gap: 30px; margin: 24px 0 0; }
.book-stats div { min-width: 90px; }
.book-stats dt { color: rgba(255,255,255,.52); font-size: 12px; }
.book-stats dd { margin: 5px 0 0; color: #fff; font: 700 20px/1 var(--serif); }
.book-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 28px; }
.book-actions .primary-button { min-width: 128px; }
.book-actions .secondary-button { color: #fff; border-color: rgba(255,255,255,.5); }
.book-actions .secondary-button:hover { background: rgba(255,255,255,.1); }
.book-actions .is-disabled { opacity: .52; }
.book-shelf-state { color: #f2dbad; font-weight: 700; }
.book-notice { margin: 20px 0 0; padding: 14px 18px; color: #725d36; background: #fff8e8; border: 1px solid #ead8ae; }
.book-notice a { color: var(--brand); font-weight: 700; }
.edition-panel { display: grid; grid-template-columns: minmax(180px, .65fr) minmax(300px, 1fr); gap: 10px 34px; align-items: center; margin-top: 28px; padding: 24px 28px; background: var(--paper-strong); border: 1px solid var(--line); }
.edition-panel h2 { margin: 0; font: 700 22px/1.3 var(--serif); }
.edition-panel form { display: flex; gap: 10px; justify-content: flex-end; }
.edition-panel select { min-width: min(360px, 70%); min-height: 42px; padding: 0 12px; border: 1px solid var(--line); background: #fff; }
.edition-panel > p { grid-column: 2; margin: 0; color: var(--muted); font-size: 13px; }
.edition-panel > p a { margin-left: 8px; color: var(--brand); }
.book-layout { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: 30px; align-items: start; margin-top: 44px; }
.book-section { margin-top: 34px; padding: 28px; background: var(--paper-strong); border: 1px solid var(--line); }
.book-layout .book-section:first-child { margin-top: 0; }
.book-section__heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; padding-bottom: 16px; border-bottom: 1px solid var(--line); }
.book-section__heading h2 { margin: 0; font: 700 25px/1.25 var(--serif); }
.book-section__heading > span, .book-section__heading > a { color: var(--muted); font-size: 13px; }
.catalog-search { display: block; margin: 20px 0 14px; }
.catalog-search input { width: 100%; min-height: 44px; padding: 0 14px; border: 1px solid var(--line); background: #fbfaf7; outline: none; }
.catalog-search input:focus { border-color: var(--brand); box-shadow: 0 0 0 3px var(--brand-soft); }
.book-catalog { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.book-catalog li { min-width: 0; border-bottom: 1px solid var(--line); }
.book-catalog li:nth-child(3n+2) { border-inline: 1px solid var(--line); }
.book-catalog a { display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 8px; padding: 15px 12px; }
.book-catalog a:hover { color: var(--brand); background: #faf6ef; }
.book-catalog span { color: var(--muted); font: 12px/1.55 Arial, sans-serif; }
.book-catalog strong { overflow: hidden; font-weight: 400; line-height: 1.55; text-overflow: ellipsis; white-space: nowrap; }
.catalog-empty { margin: 16px 0 0; color: var(--muted); text-align: center; }
.book-aside { position: sticky; top: 24px; }
.book-aside section { padding: 28px; color: #fff; background: #263f38; }
.book-aside h2 { margin: 0; font: 700 28px/1.3 var(--serif); }
.book-aside h2 a { color: #fff; }
.book-aside p:not(.page-kicker) { margin: 14px 0 0; color: rgba(255,255,255,.68); line-height: 1.75; }
.book-aside dl { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin: 22px 0; background: rgba(255,255,255,.15); }
.book-aside dl div { padding: 14px 10px; background: #263f38; }
.book-aside dt { color: rgba(255,255,255,.5); font-size: 12px; }
.book-aside dd { margin: 5px 0 0; font: 700 18px/1 var(--serif); }
.book-aside section > a { color: #f2dbad; font-size: 13px; }
.ai-summary-actions { display: flex; gap: 8px; }
.ai-summary-actions button { padding: 7px 13px; color: var(--brand); border: 1px solid var(--brand); background: #fff; cursor: pointer; }
.ai-summary-actions button:hover, .ai-summary-actions button.is-active { color: #fff; background: var(--brand); }
.ai-summary-content { min-height: 92px; margin-top: 20px; padding: 20px; color: var(--muted); line-height: 1.75; background: #f8f5ee; }
.book-qna-link { display: inline-block; margin-top: 16px; color: var(--brand); font-weight: 700; }
.related-grid { grid-template-columns: repeat(6, minmax(0, 1fr)); margin-top: 22px; gap: 14px; }
.related-grid .book-card__body { padding: 13px; }
.related-grid .book-card h3 { font-size: 16px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

@media (max-width: 980px) {
    .book-hero { grid-template-columns: 190px minmax(0, 1fr); gap: 34px; padding: 36px; }
    .book-hero__cover { width: 174px; }
    .book-layout { grid-template-columns: 1fr; }
    .book-aside { position: static; }
    .book-aside section { display: grid; grid-template-columns: 1fr 1fr; gap: 12px 24px; }
    .book-aside section > p, .book-aside section > a { grid-column: 1 / -1; }
    .related-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 760px) {
    .book-breadcrumb { margin-top: -8px; }
    .book-hero { grid-template-columns: 104px minmax(0, 1fr); gap: 20px; min-height: 0; padding: 24px 20px; align-items: start; }
    .book-hero__cover { width: 100px; border-width: 4px; }
    .book-hero h1 { font-size: 31px; }
    .book-intro { grid-column: 1 / -1; -webkit-line-clamp: 4; }
    .book-stats { gap: 16px; }
    .book-stats div { min-width: 72px; }
    .book-actions { grid-column: 1 / -1; }
    .edition-panel { grid-template-columns: 1fr; padding: 20px; }
    .edition-panel form { justify-content: stretch; }
    .edition-panel select { min-width: 0; flex: 1; }
    .edition-panel > p { grid-column: 1; }
    .book-layout { margin-top: 30px; }
    .book-section { padding: 20px; }
    .book-section__heading { align-items: flex-start; flex-direction: column; }
    .book-catalog { grid-template-columns: 1fr 1fr; }
    .book-catalog li:nth-child(3n+2) { border-inline: 0; }
    .book-catalog li:nth-child(odd) { border-right: 1px solid var(--line); }
    .book-aside section { display: block; }
    .ai-summary-actions { width: 100%; }
    .ai-summary-actions button { flex: 1; }
}
@media (max-width: 480px) {
    .book-hero { grid-template-columns: 84px minmax(0, 1fr); padding: 20px 16px; }
    .book-hero__cover { width: 80px; }
    .book-hero h1 { font-size: 27px; }
    .book-byline { margin-top: 8px; }
    .book-intro { margin-top: 16px; font-size: 13px; }
    .book-stats { grid-column: 1 / -1; }
    .book-actions .primary-button, .book-actions .secondary-button { flex: 1; min-width: 0; }
    .edition-panel form { flex-direction: column; }
    .edition-panel select { width: 100%; }
    .book-catalog { grid-template-columns: 1fr; }
    .book-catalog li:nth-child(odd) { border-right: 0; }
    .related-grid { grid-template-columns: 1fr 1fr; }
}