/* ============================================================
   读书音频馆 · 样式表（知性 / 高级感 · 改版）
   设计基调：温润纸色底 + 深墨字 + 朱红点睛 + 衬线标题 + 留白 + 细线 + 柔影
   想换风格只改下面 :root 里的变量即可：
     --paper   页面背景（纸色）
     --ink     正文颜色（墨色）
     --accent  跳跃点睛色（朱红）
   ============================================================ */
:root {
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;

  --paper: #F7F4EC;          /* 温润纸色背景（不是冷白冷灰，避免压抑） */
  --surface: #FDFBF6;        /* 卡片纸面 */
  --ink: #211E18;            /* 深墨色正文（不是纯黑，更温润） */
  --ink-soft: #6F6A5E;       /* 次要灰墨 */
  --line: #E7E0D2;           /* 细线（暖灰） */
  --accent: #C2452E;         /* 朱红 · 点睛跳跃色 */
  --accent-strong: #A8392A;  /* 朱红按下/加深 */
  --accent-tint: rgba(194, 69, 46, 0.05); /* 极淡朱红底 */

  --player-bg: #23201B;      /* 听书台：暖墨黑（不是冷黑，不压抑） */
  --player-ink: #F3EEE3;     /* 台面文字：奶白 */
  --player-soft: rgba(243, 238, 227, 0.62);

  --radius: 16px;
  --shadow-sm: 0 1px 2px rgba(33,30,24,.05), 0 10px 24px rgba(33,30,24,.05);
  --shadow-md: 0 2px 6px rgba(33,30,24,.06), 0 18px 40px rgba(33,30,24,.08);
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* 极淡纸张颗粒，增加“纸感/高级感”，几乎看不出但手感不同 */
body::before {
  content: "";
  position: fixed; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: .035;
  pointer-events: none;
  z-index: 0;
}
.site-header, .container, .site-footer { position: relative; z-index: 1; }

/* 顶部标题（衬线 + 朱红印章 + 朱红短线点睛） */
.site-header {
  text-align: center;
  padding: 56px 20px 28px;
}
.site-title {
  margin: 0;
  font-family: var(--serif);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: 3px;
}
.site-title .dot {
  display: inline-block;
  width: 11px; height: 11px;
  border-radius: 3px;
  background: var(--accent);
  margin: 0 14px;
  vertical-align: middle;
  transform: translateY(-3px);
}
.site-subtitle {
  margin: 12px 0 0;
  color: var(--ink-soft);
  font-size: 14px;
  letter-spacing: 2px;
}

/* 主体容器：手机占满，电脑居中且不过宽 */
.container {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 16px 40px;
}

/* 听书台（播放器）：暖墨黑卡片，奶白字，朱红为焦点 */
.player-card {
  background: var(--player-bg);
  color: var(--player-ink);
  border: 1px solid rgba(255,255,255,.05);
  border-radius: 20px;
  padding: 26px 24px 30px;
  box-shadow: var(--shadow-md);
  margin-bottom: 32px;
}
.now-playing { margin-bottom: 20px; }
.np-label {
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--player-soft);
}
.np-title {
  margin: 6px 0 4px;
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 600;
  word-break: break-word;
}
.np-meta {
  margin: 0;
  font-size: 13px;
  color: var(--player-soft);
}

/* 进度条（朱红填充，随播放跳动） */
.progress-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}
.time {
  font-size: 12px;
  color: var(--player-soft);
  min-width: 38px;
  text-align: center;
  font-variant-numeric: tabular-nums;
}
.progress {
  -webkit-appearance: none;
  appearance: none;
  flex: 1;
  height: 5px;
  border-radius: 5px;
  background: linear-gradient(to right,
              var(--accent) var(--p, 0%),
              rgba(243,238,227,.18) var(--p, 0%));
  outline: none;
  cursor: pointer;
}
.progress::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 15px; height: 15px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(194,69,46,.18);
  cursor: pointer;
}
.progress::-moz-range-thumb {
  width: 15px; height: 15px;
  border: none;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
}

/* 控制按钮 */
.controls {
  display: flex;
  align-items: center;
  gap: 14px;
}
.btn {
  background: rgba(243,238,227,.10);
  color: var(--player-ink);
  border: none;
  width: 46px; height: 46px;
  border-radius: 50%;
  font-size: 16px;
  cursor: pointer;
  transition: background .15s ease, transform .05s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.btn:hover { background: rgba(243,238,227,.18); }
.btn:active { transform: scale(.96); }
.btn-play {
  width: 58px; height: 58px;
  font-size: 21px;
  background: var(--accent);
  color: #fff;
  box-shadow: 0 8px 20px rgba(194,69,46,.35);
}
.btn-play:hover { background: var(--accent-strong); }
.speed {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 13px;
  color: var(--player-soft);
}
.speed select {
  background: rgba(243,238,227,.10);
  color: var(--player-ink);
  border: 1px solid rgba(243,238,227,.18);
  border-radius: 9px;
  padding: 6px 9px;
  font-size: 13px;
}
.speed select option { color: #211E18; }

/* 播放列表 */
.playlist-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 14px;
  padding: 0 2px;
}
.playlist-head h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 1px;
}
.count {
  font-size: 13px;
  color: var(--ink-soft);
}
.playlist {
  list-style: none;
  margin: 0; padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.track {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  cursor: pointer;
  transition: border-color .18s ease, transform .12s ease, box-shadow .18s ease, background .18s ease;
  display: flex;
  gap: 15px;
  align-items: flex-start;
}
.track:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}
.track.active {
  border-color: var(--accent);
  background: var(--accent-tint);
  box-shadow: var(--shadow-sm);
}
.track-index {
  flex: 0 0 auto;
  width: 30px; height: 30px;
  border-radius: 50%;
  background: #F1ECE0;
  border: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--serif);
  font-size: 14px;
  color: var(--ink-soft);
  margin-top: 2px;
}
.track.active .track-index {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.track-body { flex: 1; min-width: 0; }
.track-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}
.track-title {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  word-break: break-word;
}
.track-date {
  flex: 0 0 auto;
  font-size: 12px;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}
.track-book {
  font-size: 13px;
  color: var(--ink-soft);
  margin: 3px 0 0;
}
.track-note {
  font-size: 13px;
  color: #4A453B;
  margin: 8px 0 0;
  padding-left: 11px;
  border-left: 2px solid rgba(194,69,46,.35);
}
.empty-hint {
  color: var(--ink-soft);
  font-size: 14px;
  background: var(--surface);
  border: 1px dashed var(--line);
  border-radius: var(--radius);
  padding: 20px;
}
.empty-hint code {
  background: var(--paper);
  padding: 1px 6px;
  border-radius: 6px;
  font-size: 13px;
}

/* 页脚 */
.site-footer {
  text-align: center;
  color: var(--ink-soft);
  font-size: 12px;
  letter-spacing: 1px;
  padding: 8px 16px 44px;
}

/* 书架（首页） */
.shelf-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.shelf-top h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 1px;
}
.search {
  flex: 0 1 240px;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 9px 16px;
  outline: none;
}
.search:focus { border-color: var(--accent); }
.search::placeholder { color: var(--ink-soft); }

.book-list {
  list-style: none;
  margin: 0; padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
}
.series-head {
  grid-column: 1 / -1;          /* 占满整行，作为分组标题 */
  list-style: none;
  font-family: var(--serif);
  color: var(--accent);
  font-size: 13px;
  letter-spacing: 3px;
  margin: 22px 0 2px;
  padding-left: 12px;
  border-left: 3px solid var(--accent);
  line-height: 1.1;
}
.book-card {
  display: flex;
  gap: 14px;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
  cursor: pointer;
  transition: border-color .18s ease, transform .12s ease, box-shadow .18s ease;
}
.book-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}
.book-card.group-end:not(:last-child) {
  /* 每组的最后一张卡片与下一组首张之间留出明显空隙（额外 24px + grid gap 12px ≈ 36px），
     避免分组末尾的卡片与散书在视觉上"连在一起"；排除整列表最后一张避免底部多余留白。 */
  margin-bottom: 24px;
}
.book-cover {
  flex: 0 0 auto;
  width: 46px; height: 46px;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  display: flex; align-items: center; justify-content: center;
}
.book-meta { min-width: 0; }
.book-name {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  word-break: break-word;
}
.book-by {
  margin-top: 3px;
  font-size: 12px;
  color: var(--ink-soft);
}

/* 书详情 */
.back {
  background: none;
  border: 1px solid var(--line);
  color: var(--ink-soft);
  border-radius: 999px;
  padding: 7px 14px;
  font-size: 13px;
  cursor: pointer;
  margin-bottom: 14px;
  transition: border-color .15s ease, color .15s ease;
}
.back:hover { border-color: var(--accent); color: var(--accent); }
.book-title {
  margin: 0;
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 1px;
}
.book-author {
  margin: 6px 0 18px;
  color: var(--ink-soft);
  font-size: 14px;
}
.book-series {
  margin: 4px 0 2px;
  font-family: var(--serif);
  color: var(--accent);
  font-size: 14px;
  letter-spacing: 1px;
}
.book-series[hidden] { display: none; }
.book-info {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  margin-bottom: 14px;
}
.book-info h3 {
  margin: 0 0 8px;
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 600;
}
.book-info h3::before {
  content: "";
  display: inline-block;
  width: 8px; height: 8px;
  border-radius: 2px;
  background: var(--accent);
  margin-right: 9px;
  vertical-align: middle;
}
.book-info p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: #4A453B;
}
.chapters { margin-top: 6px; }
.chapters h3 {
  margin: 0 0 12px;
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 600;
}
.chapter-list {
  list-style: none;
  margin: 0; padding: 0;
  display: flex; flex-direction: column; gap: 10px;
}
.chapter {
  display: flex;
  gap: 13px;
  align-items: flex-start;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
  cursor: pointer;
  transition: border-color .18s ease, transform .12s ease, box-shadow .18s ease;
}
.chapter:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}
.chapter.active {
  border-color: var(--accent);
  background: var(--accent-tint);
}
.ch-index {
  flex: 0 0 auto;
  width: 28px; height: 28px;
  border-radius: 50%;
  background: #F1ECE0;
  border: 1px solid var(--line);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--serif);
  font-size: 13px;
  color: var(--ink-soft);
}
.chapter.active .ch-index {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.ch-body { flex: 1; min-width: 0; }
.ch-title {
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 600;
  word-break: break-word;
}
.ch-date {
  margin-left: 10px;
  font-size: 12px;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}
.ch-note {
  margin: 7px 0 0;
  font-size: 13px;
  color: #4A453B;
  padding-left: 11px;
  border-left: 2px solid rgba(194,69,46,.35);
}

/* 手机上更紧凑一点 */
@media (max-width: 480px) {
  .site-header { padding: 40px 16px 22px; }
  .site-title { font-size: 26px; letter-spacing: 2px; }
  .player-card { padding: 22px 18px 26px; }
  .btn { width: 42px; height: 42px; }
  .btn-play { width: 52px; height: 52px; }
  .shelf-top { flex-wrap: wrap; }
  .search { flex-basis: 100%; }
  .book-title { font-size: 22px; }
  .book-list { grid-template-columns: 1fr; }
}