/* ===== 水墨风格 · 汴州往事 ===== */

@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;700;900&display=swap');

:root {
  --paper: #1a1a1e;
  --paper-light: #222226;
  --ink: #d8d0c8;
  --ink-light: #9a9088;
  --ink-faint: #6b6260;
  --vermilion: #c45a4a;
  --vermilion-light: #d4785a;
  --sidebar-w: 220px;
  --max-width: 680px;
}

/* ===== Reset ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html {
  font-size: 18px;
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Serif SC", "Source Han Serif SC", "SimSun", "Songti SC", serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.9;
  min-height: 100vh;
}

a { color: var(--vermilion); text-decoration: none; transition: color 0.3s; }
a:hover { color: var(--vermilion-light); }

/* ===== 首页 ===== */
.home {
  max-width: 800px;
  margin: 0 auto;
  padding: 80px 24px 120px;
}

.home-header {
  text-align: center;
  margin-bottom: 64px;
  position: relative;
}

.home-header::before {
  content: "";
  display: block;
  width: 60px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--ink-faint), transparent);
  margin: 0 auto 32px;
}

.site-title {
  font-size: 2.2rem;
  font-weight: 900;
  letter-spacing: 0.15em;
  color: var(--ink);
  margin-bottom: 8px;
}

.site-subtitle {
  font-size: 0.85rem;
  color: var(--ink-faint);
  letter-spacing: 0.3em;
  font-weight: 400;
}

.site-desc {
  margin-top: 24px;
  font-size: 0.9rem;
  color: var(--ink-light);
  line-height: 1.8;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

/* 章节列表 */
.chapter-list {
  list-style: none;
}

.chapter-item {
  border-bottom: 1px solid rgba(100,90,80,0.25);
}

.chapter-link {
  display: flex;
  align-items: baseline;
  padding: 18px 8px;
  transition: all 0.3s ease;
  position: relative;
}

.chapter-link::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 0;
  background: var(--vermilion);
  transition: height 0.3s ease;
}

.chapter-link:hover {
  padding-left: 16px;
}

.chapter-link:hover::before {
  height: 60%;
}

.chapter-num {
  font-size: 0.75rem;
  color: var(--ink-faint);
  min-width: 36px;
  font-variant-numeric: tabular-nums;
}

.chapter-title {
  font-size: 1.05rem;
  color: var(--ink);
  flex: 1;
}

.chapter-link:hover .chapter-title {
  color: var(--vermilion);
}

/* 首页装饰 */
.home-footer {
  margin-top: 64px;
  text-align: center;
}

.home-footer .seal {
  display: inline-block;
  border: 2px solid var(--vermilion);
  color: var(--vermilion);
  font-size: 0.75rem;
  padding: 6px 10px;
  letter-spacing: 0.1em;
  opacity: 0.6;
  transform: rotate(-3deg);
}

.footer-author {
  margin-top: 24px;
  font-size: 0.8rem;
  color: var(--ink-light);
  letter-spacing: 0.1em;
}

.footer-contact {
  margin-top: 6px;
  font-size: 0.72rem;
  color: var(--ink-faint);
  letter-spacing: 0.05em;
}

.site-footer {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid rgba(100,90,80,0.2);
  text-align: center;
}

/* ===== 侧边栏导航 ===== */
.sidebar {
  position: fixed;
  left: 0;
  top: 0;
  width: var(--sidebar-w);
  height: 100vh;
  background: var(--paper-light);
  border-right: 1px solid rgba(100,90,80,0.2);
  overflow-y: auto;
  z-index: 100;
  padding: 24px 0;
}

.sidebar::-webkit-scrollbar { width: 3px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--ink-faint); border-radius: 2px; }

.sidebar-title {
  font-size: 0.8rem;
  color: var(--ink-faint);
  letter-spacing: 0.2em;
  text-align: center;
  padding: 0 16px 16px;
  border-bottom: 1px solid rgba(100,90,80,0.2);
  margin-bottom: 8px;
}

.sidebar-title a {
  color: var(--ink-faint);
  font-size: 0.75rem;
  display: block;
  margin-top: 6px;
}

.sidebar-title a:hover { color: var(--vermilion); }

.sidebar-list {
  list-style: none;
}

.sidebar-item a {
  display: flex;
  align-items: baseline;
  padding: 10px 16px;
  font-size: 0.78rem;
  color: var(--ink-light);
  transition: all 0.25s ease;
  border-left: 2px solid transparent;
}

.sidebar-item a:hover {
  color: var(--ink);
  background: rgba(255,255,255,0.03);
  border-left-color: var(--vermilion);
}

.sidebar-item.active a {
  color: var(--vermilion);
  border-left-color: var(--vermilion);
  font-weight: 700;
}

.sidebar-item .s-num {
  color: var(--ink-faint);
  min-width: 28px;
  font-variant-numeric: tabular-nums;
}

/* ===== 章节页面 ===== */
.chapter-page {
  margin-left: var(--sidebar-w);
  padding: 60px 40px 80px;
  /* 内容在侧边栏右侧居中 */
  display: flex;
  flex-direction: column;
  align-items: center;
}

.chapter-page > * {
  width: 100%;
  max-width: var(--max-width);
}

/* 章节头部 */
.chapter-header {
  text-align: center;
  margin-bottom: 56px;
  position: relative;
}

.chapter-header::after {
  content: "";
  display: block;
  width: 120px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--ink-faint), transparent);
  margin: 32px auto 0;
}

.chapter-name {
  font-size: 1.6rem;
  font-weight: 900;
  letter-spacing: 0.12em;
  color: var(--ink);
  position: relative;
  display: inline-block;
}

/* 章节标题两侧装饰 */
.chapter-name::before,
.chapter-name::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 24px;
  height: 1px;
  background: var(--ink-faint);
}

.chapter-name::before { right: calc(100% + 12px); }
.chapter-name::after  { left: calc(100% + 12px); }

/* 正文 */
.prose {
  font-size: 1rem;
  line-height: 1.9;
  color: var(--ink);
}

.prose p {
  text-indent: 2em;
  margin-bottom: 0.6em;
}

.prose p:first-child {
  text-indent: 0;
}

.prose p:first-child::first-letter {
  font-size: 2.4em;
  float: left;
  line-height: 1;
  margin: 0.05em 0.1em 0 0;
  color: var(--ink);
  font-weight: 900;
}

.prose hr {
  border: none;
  text-align: center;
  margin: 2em 0;
}

.prose hr::before {
  content: "◆";
  color: var(--ink-faint);
  font-size: 0.6rem;
  letter-spacing: 0.5em;
}

.prose em {
  font-style: normal;
  color: var(--ink-light);
}

.prose strong {
  font-weight: 700;
  color: var(--vermilion);
}

/* 引用/对话 */
.prose blockquote {
  border-left: 2px solid var(--ink-faint);
  padding-left: 1em;
  margin: 1em 0;
  color: var(--ink-light);
  font-style: italic;
}

/* ===== 底部导航 ===== */
.chapter-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 64px;
  padding-top: 32px;
  border-top: 1px solid rgba(100,90,80,0.25);
}

.nav-link {
  font-size: 0.85rem;
  color: var(--ink-light);
  transition: color 0.3s;
  max-width: 45%;
}

.nav-link:hover { color: var(--vermilion); }

.nav-prev { text-align: left; }
.nav-next { text-align: right; }
.nav-prev::before { content: "← "; opacity: 0.5; }
.nav-next::after  { content: " →"; opacity: 0.5; }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .sidebar { display: none; }
  .chapter-page { margin-left: 0; padding: 40px 20px 60px; }
}

@media (max-width: 600px) {
  html { font-size: 16px; }
  .home { padding: 48px 16px 80px; }
  .chapter-page { padding: 40px 16px 60px; }
  .site-title { font-size: 1.6rem; letter-spacing: 0.08em; }
  .chapter-name { font-size: 1.3rem; }
  .chapter-name::before,
  .chapter-name::after { display: none; }
  .chapter-link { padding: 14px 4px; }
}