/* Book-like reader for the Chinese poetry collection. */
body.poem-reader-page {
  --poem-ink: #18283a;
  --poem-muted: #647587;
  --poem-line: #d6e0e8;
  --poem-panel: #f3f7fa;
  --poem-paper: #ffffff;
  --poem-blue: #0068b5;
  margin: 0;
  background: var(--poem-panel);
  color: var(--poem-ink);
  font-family: Arial, "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

body.poem-reader-page .top-nav,
body.poem-reader-page .modern-legacy-content {
  display: none !important;
}

.poem-reader-shell {
  width: min(calc(100% - 40px), 1320px);
  min-height: calc(100vh - 92px);
  margin: 0 auto;
  padding: 42px 0 64px;
  display: grid;
  grid-template-columns: 224px minmax(0, 1fr);
  gap: 38px;
  align-items: start;
}

.poem-reader-sidebar {
  position: sticky;
  top: 126px;
  border-right: 1px solid var(--poem-line);
  padding: 8px 28px 12px 0;
}

.poem-reader-kicker {
  margin: 0 0 10px;
  color: var(--poem-blue);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.poem-reader-sidebar h1 {
  margin: 0;
  color: var(--poem-ink);
  font-size: 27px;
  font-weight: 400;
  line-height: 1.2;
}

.poem-reader-sidebar-intro {
  margin: 16px 0 26px;
  color: var(--poem-muted);
  font-size: 13px;
  line-height: 1.7;
}

.poem-reader-section-list {
  display: grid;
  gap: 8px;
}

.poem-reader-section-button {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid transparent;
  border-left: 3px solid transparent;
  background: transparent;
  color: var(--poem-ink);
  font: inherit;
  font-size: 15px;
  line-height: 1.45;
  text-align: left;
  cursor: pointer;
  transition: color .18s ease, background-color .18s ease, border-color .18s ease;
}

.poem-reader-section-button:hover,
.poem-reader-section-button.is-active {
  border-color: var(--poem-line);
  border-left-color: var(--poem-blue);
  background: var(--poem-paper);
  color: var(--poem-blue);
}

.poem-reader-section-count {
  display: block;
  margin-top: 3px;
  color: var(--poem-muted);
  font-size: 12px;
  font-weight: 400;
}

.poem-reader-main {
  min-width: 0;
}

.poem-reader-heading {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: end;
  margin-bottom: 22px;
}

.poem-reader-heading h2 {
  margin: 0;
  color: var(--poem-ink);
  font-size: clamp(27px, 4vw, 44px);
  font-weight: 400;
  line-height: 1.15;
}

.poem-reader-heading p {
  max-width: 360px;
  margin: 0;
  color: var(--poem-muted);
  font-size: 13px;
  line-height: 1.7;
  text-align: right;
}

.poem-book-frame {
  position: relative;
  padding: 14px;
  border: 1px solid #cbd7e0;
  background: #e8eef3;
  box-shadow: 0 18px 42px rgba(17, 24, 39, .12);
  perspective: 1800px;
}

.poem-book-frame::before {
  content: "";
  position: absolute;
  top: 14px;
  bottom: 14px;
  left: 50%;
  z-index: 2;
  width: 1px;
  background: #c8d1d8;
  box-shadow: 1px 0 0 rgba(255, 255, 255, .86);
  pointer-events: none;
}

.poem-book-spread {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  min-height: 640px;
  transform-style: preserve-3d;
}

.poem-book-page {
  position: relative;
  min-width: 0;
  padding: 44px clamp(25px, 4vw, 60px) 54px;
  border: 1px solid #e1e7ec;
  background: var(--poem-paper);
  color: var(--poem-ink);
  text-align: left;
  cursor: pointer;
  overflow: hidden;
}

.poem-book-page:first-child {
  border-right: 0;
  box-shadow: inset -16px 0 26px -28px rgba(17, 24, 39, .45);
}

.poem-book-page:last-child {
  border-left: 0;
  box-shadow: inset 16px 0 26px -28px rgba(17, 24, 39, .45);
}

.poem-book-page:hover { background: #fcfdfe; }

.poem-book-page:focus-visible {
  outline: 3px solid rgba(0, 104, 181, .35);
  outline-offset: -4px;
}

.poem-book-page.is-blank {
  background: #f8fafb;
  cursor: default;
}

.poem-book-page::after {
  position: absolute;
  bottom: 18px;
  color: #98a7b3;
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
}

.poem-book-page:first-child::after {
  content: "上一页";
  left: clamp(25px, 4vw, 60px);
}

.poem-book-page:last-child::after {
  content: "下一页";
  right: clamp(25px, 4vw, 60px);
}

.poem-book-page.is-blank::after { content: ""; }

.poem-book-page-content {
  height: 100%;
  max-height: 542px;
  overflow: auto;
  scrollbar-color: #bccbd7 transparent;
  scrollbar-width: thin;
}

.poem-book-page-label {
  margin: 0 0 18px;
  color: var(--poem-blue);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .13em;
  text-transform: uppercase;
}

.poem-book-page h3.poem-title,
.poem-book-page .poem-title {
  margin: 0 0 24px;
  color: var(--poem-ink);
  font-size: clamp(20px, 2.5vw, 29px);
  font-weight: 400;
  line-height: 1.35;
  text-align: left;
}

.poem-book-page .poem-intro {
  margin: 0 0 22px;
  padding: 15px 17px;
  border-left: 3px solid var(--poem-blue);
  border-radius: 0;
  background: #f2f6f9;
  color: var(--poem-muted);
  font-size: 13px;
  line-height: 1.85;
  text-indent: 0;
}

.poem-book-page .poem-body {
  margin: 22px 0 0;
  color: #25384a;
  font-family: "STZhongsong", "SimSun", "Songti SC", "KaiTi", serif;
  font-size: clamp(16px, 1.65vw, 20px);
  line-height: 2.15;
  letter-spacing: .06em;
  text-align: center;
}

.poem-book-page .poem-notes {
  margin: 0;
  padding: 0;
  border: 0;
  color: #52687a;
  font-size: 14px;
  line-height: 1.9;
}

.poem-book-page .poem-notes strong {
  display: inline-block;
  margin-bottom: 10px;
  color: var(--poem-blue);
  font-size: 15px;
  font-weight: 700;
}

.poem-book-page .img-group {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin: 18px 0;
}

.poem-book-page .img-group img {
  max-width: 100%;
  height: auto;
  border: 1px solid #dbe4eb;
  border-radius: 0;
  box-shadow: 0 8px 18px rgba(17, 24, 39, .08);
}

.poem-book-page .book-notes-title {
  margin: 0 0 24px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--poem-line);
  color: var(--poem-muted);
  font-size: 13px;
  font-weight: 400;
}

.poem-book-page .book-notes-title strong {
  display: block;
  margin-top: 5px;
  color: var(--poem-ink);
  font-size: 19px;
  font-weight: 400;
}

.poem-book-page .poem-card {
  min-height: 0;
  margin: 0;
  padding: 0;
  border: 0;
  background: transparent;
  box-shadow: none;
}

.poem-book-page .poem-card:hover {
  transform: none;
  box-shadow: none;
}

.poem-reader-status {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: center;
  margin-top: 16px;
  color: var(--poem-muted);
  font-size: 12px;
}

.poem-reader-status strong {
  color: var(--poem-ink);
  font-weight: 700;
}

.poem-reader-hint { text-align: right; }

.poem-book-spread.is-turning-next .poem-book-page:last-child {
  animation: poem-page-next .42s cubic-bezier(.2, .7, .2, 1);
}

.poem-book-spread.is-turning-prev .poem-book-page:first-child {
  animation: poem-page-prev .42s cubic-bezier(.2, .7, .2, 1);
}

@keyframes poem-page-next {
  0% { transform: rotateY(0); opacity: 1; }
  45% { transform: rotateY(-78deg); opacity: .72; }
  100% { transform: rotateY(0); opacity: 1; }
}

@keyframes poem-page-prev {
  0% { transform: rotateY(0); opacity: 1; }
  45% { transform: rotateY(78deg); opacity: .72; }
  100% { transform: rotateY(0); opacity: 1; }
}

@media (max-width: 980px) {
  .poem-reader-shell {
    width: min(calc(100% - 28px), 760px);
    grid-template-columns: 1fr;
    gap: 24px;
    padding-top: 28px;
  }

  .poem-reader-sidebar {
    position: static;
    border-right: 0;
    border-bottom: 1px solid var(--poem-line);
    padding: 0 0 20px;
  }

  .poem-reader-sidebar-intro { max-width: 560px; }

  .poem-reader-section-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .poem-reader-section-button { border-left: 0; border-bottom: 3px solid transparent; }
  .poem-reader-section-button:hover,
  .poem-reader-section-button.is-active { border-left-color: transparent; border-bottom-color: var(--poem-blue); }
}

@media (max-width: 680px) {
  .poem-reader-heading { display: block; }
  .poem-reader-heading p { margin-top: 12px; text-align: left; }
  .poem-book-frame { padding: 8px; }
  .poem-book-frame::before { display: none; }
  .poem-book-spread { grid-template-columns: 1fr; min-height: 0; }
  .poem-book-page { min-height: 430px; padding: 30px 24px 50px; }
  .poem-book-page:first-child { border-right: 1px solid #e1e7ec; border-bottom: 0; }
  .poem-book-page:last-child { border-left: 1px solid #e1e7ec; border-top: 0; }
  .poem-book-page:last-child::after { right: 24px; }
  .poem-book-page:first-child::after { left: 24px; }
  .poem-book-page-content { max-height: 480px; }
  .poem-reader-section-list { grid-template-columns: 1fr; gap: 5px; }
  .poem-reader-status { display: block; }
  .poem-reader-hint { margin-top: 6px; text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  .poem-book-spread.is-turning-next .poem-book-page:last-child,
  .poem-book-spread.is-turning-prev .poem-book-page:first-child { animation: none; }
}