/* 《周期》章节阅读 - 共用样式 */
* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --ink: #1c1c1e;
  --ink-soft: #3a3a3c;
  --ink-light: #6e6e73;
  --paper: #faf8f3;
  --paper-card: #fffdf7;
  --accent: #8b4513;
  --accent-soft: #c49a6c;
  --line: #e8e2d4;
  --highlight: #fdf3d8;
  --quote-bg: #f5efdf;
  --extra-bg: #f0eadb;
}
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Noto Serif SC", "Source Han Serif SC", "Songti SC", Georgia, serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.92;
  font-size: 16.5px;
}
.top-bar {
  background: #2c2823;
  color: #e8e2d4;
  padding: 14px 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,0.15);
}
.top-bar .book-name {
  font-size: 18px;
  letter-spacing: 4px;
  font-weight: 700;
}
.top-bar .book-name small {
  color: var(--accent-soft);
  font-size: 12px;
  margin-left: 8px;
  letter-spacing: 1px;
  font-weight: normal;
}
.top-bar nav { display: flex; gap: 18px; align-items: center; font-size: 14px; }
.top-bar nav a {
  color: #e8e2d4;
  text-decoration: none;
  padding: 6px 14px;
  border-radius: 4px;
  transition: all 0.2s;
}
.top-bar nav a:hover { background: rgba(196,154,108,0.2); color: #fff; }
.top-bar nav a.current {
  background: var(--accent);
  color: #fff;
}
.container {
  max-width: 820px;
  margin: 0 auto;
  padding: 48px 40px 80px;
}
.chapter-meta {
  text-align: center;
  margin-bottom: 40px;
  color: var(--ink-light);
  font-size: 13px;
  letter-spacing: 3px;
}
.chapter-meta .part-label {
  color: var(--accent);
  margin-bottom: 8px;
}
.chapter-title-block {
  text-align: center;
  margin-bottom: 50px;
  padding-bottom: 36px;
  border-bottom: 2px solid var(--accent);
}
.chapter-num-big {
  font-size: 70px;
  color: var(--accent-soft);
  font-weight: 200;
  letter-spacing: 2px;
  line-height: 1;
  margin-bottom: 8px;
  font-family: Georgia, serif;
}
.chapter-title-big {
  font-size: 36px;
  color: var(--ink);
  letter-spacing: 8px;
  font-weight: 700;
  margin-bottom: 12px;
}
.chapter-subtitle {
  color: var(--ink-light);
  letter-spacing: 4px;
  font-size: 14px;
}
.lead-quote {
  background: var(--quote-bg);
  border-left: 5px solid var(--accent);
  padding: 24px 28px;
  margin: 32px 0 48px;
  border-radius: 0 6px 6px 0;
  line-height: 1.92;
  font-size: 16px;
  color: var(--ink-soft);
  position: relative;
}
.lead-quote::before {
  content: "「 卷首语 」";
  display: block;
  color: var(--accent);
  font-weight: 700;
  letter-spacing: 3px;
  font-size: 13px;
  margin-bottom: 12px;
}
h2.section {
  font-size: 24px;
  color: var(--ink);
  margin: 48px 0 20px;
  padding: 12px 0 12px 18px;
  border-left: 5px solid var(--accent);
  background: linear-gradient(to right, var(--highlight), transparent);
  letter-spacing: 3px;
  font-weight: 700;
}
h3.sub {
  font-size: 19px;
  color: var(--accent);
  margin: 32px 0 14px;
  letter-spacing: 2px;
  font-weight: 700;
}
h4.minor {
  font-size: 16.5px;
  color: var(--ink);
  margin: 22px 0 10px;
  font-weight: 700;
}
p {
  margin-bottom: 16px;
  color: var(--ink-soft);
  text-indent: 2em;
}
ul, ol {
  margin: 12px 0 18px 36px;
  color: var(--ink-soft);
}
li { margin-bottom: 8px; }
strong { color: var(--accent); font-weight: 700; }
em { color: var(--ink); font-style: normal; background: var(--highlight); padding: 1px 4px; border-radius: 2px; }
.highlight-box {
  background: var(--highlight);
  border: 1px solid #eed9a7;
  border-radius: 6px;
  padding: 22px 26px;
  margin: 22px 0;
}
.highlight-box .title {
  color: var(--accent);
  font-weight: 700;
  letter-spacing: 2px;
  margin-bottom: 12px;
  font-size: 15px;
}
.highlight-box ul, .highlight-box ol { margin-left: 24px; margin-bottom: 0; }
.highlight-box p { text-indent: 0; }
.quote {
  background: var(--quote-bg);
  padding: 18px 26px;
  margin: 22px 0;
  border-radius: 4px;
  font-style: italic;
  color: var(--ink-soft);
  border-left: 3px solid var(--accent-soft);
}
.quote p { text-indent: 0; margin-bottom: 8px; font-style: italic; }
.quote .source {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-light);
  text-align: right;
  font-style: normal;
}
.case-box {
  background: var(--extra-bg);
  border: 2px dashed var(--accent-soft);
  border-radius: 6px;
  padding: 22px 26px;
  margin: 24px 0;
}
.case-box .case-label {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 3px 12px;
  border-radius: 3px;
  font-size: 12px;
  letter-spacing: 2px;
  margin-bottom: 12px;
}
.case-box h4 { margin-top: 14px; }
.case-box p { text-indent: 0; margin-bottom: 8px; }
table {
  width: 100%;
  border-collapse: collapse;
  margin: 22px 0;
  font-size: 15px;
}
th, td {
  padding: 12px 16px;
  border: 1px solid var(--line);
  text-align: left;
  color: var(--ink-soft);
  vertical-align: top;
}
th {
  background: var(--quote-bg);
  color: var(--accent);
  font-weight: 700;
}
.pendulum {
  background: linear-gradient(to right, #fde8c8, #fdf3d8);
  border-radius: 6px;
  padding: 22px 26px;
  margin: 22px 0;
}
.pendulum .title {
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: 2px;
  font-size: 15px;
}
.pendulum ul { list-style: none; margin: 0; columns: 2; column-gap: 30px; }
.pendulum li {
  padding: 5px 0;
  color: var(--ink-soft);
  font-size: 15px;
  break-inside: avoid;
}
.pendulum li::before { content: "⇌  "; color: var(--accent); font-weight: bold; }
.bottom-nav {
  margin-top: 60px;
  padding-top: 36px;
  border-top: 2px solid var(--line);
  display: flex;
  justify-content: space-between;
  gap: 20px;
}
.bottom-nav a {
  flex: 1;
  display: block;
  padding: 18px 22px;
  background: var(--paper-card);
  border: 1px solid var(--line);
  border-radius: 6px;
  text-decoration: none;
  color: var(--ink-soft);
  transition: all 0.2s;
  max-width: 48%;
}
.bottom-nav a:hover {
  border-color: var(--accent);
  background: var(--highlight);
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(139,69,19,0.15);
}
.bottom-nav a.prev::before { content: "← "; color: var(--accent); }
.bottom-nav a.next { text-align: right; }
.bottom-nav a.next::after { content: " →"; color: var(--accent); }
.bottom-nav a small {
  display: block;
  color: var(--ink-light);
  font-size: 12px;
  margin-bottom: 4px;
  letter-spacing: 2px;
}
.bottom-nav a .nav-title {
  font-size: 16px;
  color: var(--ink);
  font-weight: 700;
  letter-spacing: 2px;
}
.bottom-nav a.disabled {
  opacity: 0.4;
  pointer-events: none;
}
footer {
  margin-top: 60px;
  padding: 24px 0;
  text-align: center;
  color: var(--ink-light);
  font-size: 13px;
  border-top: 1px solid var(--line);
}
.toc-link {
  display: inline-block;
  margin-top: 20px;
  padding: 8px 18px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  border-radius: 4px;
  font-size: 14px;
  letter-spacing: 2px;
}
.toc-link:hover { background: var(--accent-soft); }
@media (max-width: 720px) {
  .container { padding: 28px 18px 60px; }
  .top-bar { padding: 12px 16px; flex-wrap: wrap; gap: 8px; }
  .top-bar nav { font-size: 12px; gap: 8px; flex-wrap: wrap; }
  .top-bar nav a { padding: 4px 8px; }
  .chapter-title-big { font-size: 26px; letter-spacing: 4px; }
  .chapter-num-big { font-size: 50px; }
  h2.section { font-size: 20px; }
  .pendulum ul { columns: 1; }
  .bottom-nav { flex-direction: column; }
  .bottom-nav a { max-width: 100%; }
}