/* ============================================================
   道德经 · 阅读站
   ============================================================ */

:root {
  --bg:        #f7f4ec;
  --bg-soft:   #fdfbf5;
  --bg-sunk:   #efeadd;
  --ink:       #232019;
  --ink-2:     #565045;
  --ink-3:     #8d8578;
  --line:      #e3ddcd;
  --line-soft: #efe9db;
  --accent:    #9c3b2e;
  --accent-2:  #7a5c2e;
  --accent-bg: rgba(156, 59, 46, .07);
  --shadow:    0 1px 2px rgba(60, 45, 20, .05), 0 8px 28px -18px rgba(60, 45, 20, .35);
  --serif: "Songti SC", "STSong", "Source Han Serif SC", "Noto Serif SC", "SimSun", "Times New Roman", serif;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --fs: 1rem;
}

[data-theme="dark"] {
  --bg:        #16161a;
  --bg-soft:   #1d1d22;
  --bg-sunk:   #101014;
  --ink:       #e8e4da;
  --ink-2:     #a9a49a;
  --ink-3:     #736e66;
  --line:      #2c2c33;
  --line-soft: #24242a;
  --accent:    #d08156;
  --accent-2:  #b39462;
  --accent-bg: rgba(208, 129, 86, .12);
  --shadow:    0 1px 2px rgba(0, 0, 0, .3), 0 10px 30px -20px rgba(0, 0, 0, .8);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: calc(1rem * var(--fs));
  line-height: 1.9;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background-color .3s ease, color .3s ease;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  opacity: .5;
  background-image: radial-gradient(circle at 12% 8%, var(--accent-bg), transparent 42%),
                    radial-gradient(circle at 88% 92%, var(--accent-bg), transparent 46%);
}

a { color: inherit; text-decoration: none; }

.wrap {
  width: 100%;
  max-width: 880px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

::selection { background: var(--accent); color: var(--bg); }

/* ---------------- 顶栏 ---------------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line-soft);
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: 62px;
}

.brand { display: flex; align-items: center; gap: 12px; }

.brand-mark {
  width: 34px; height: 34px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--accent);
  color: var(--bg-soft);
  font-size: 1.15rem;
  line-height: 1;
  padding-bottom: 2px;
}

.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-text b { font-size: 1.02rem; letter-spacing: .12em; font-weight: 600; }
.brand-text i {
  font-style: normal;
  font-family: var(--sans);
  font-size: .68rem;
  letter-spacing: .16em;
  color: var(--ink-3);
}

.tools { display: flex; gap: 6px; }

.tool {
  width: 36px; height: 36px;
  display: grid; place-items: center;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: var(--bg-soft);
  color: var(--ink-2);
  cursor: pointer;
  font-family: var(--serif);
  font-size: .95rem;
  transition: all .18s ease;
}
.tool:hover { color: var(--ink); border-color: var(--accent); background: var(--accent-bg); }
.tool-ico { line-height: 1; }

.progress { height: 2px; background: transparent; }
.progress i {
  display: block; height: 100%; width: 0;
  background: var(--accent);
  transition: width .25s ease;
}

/* ---------------- 首页 Hero ---------------- */

.hero { padding: 64px 0 40px; text-align: center; }

.hero-sub {
  margin: 0 0 18px;
  font-size: .95rem;
  letter-spacing: .28em;
  color: var(--ink-3);
}

.hero-title {
  margin: 0 0 22px;
  font-size: clamp(2.6rem, 9vw, 4rem);
  font-weight: 500;
  letter-spacing: .3em;
  text-indent: .3em;
  line-height: 1.15;
}

.hero-desc {
  max-width: 40em;
  margin: 0 auto;
  font-size: .93rem;
  line-height: 2.1;
  color: var(--ink-2);
  text-align: justify;
}
.hero-desc strong { color: var(--accent); font-weight: 600; }

.hero-meta { margin-top: 26px; display: flex; justify-content: center; gap: 10px; flex-wrap: wrap; }

.chip {
  font-family: var(--sans);
  font-size: .72rem;
  letter-spacing: .1em;
  padding: 5px 13px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--ink-3);
  background: var(--bg-soft);
}
.chip-btn { cursor: pointer; transition: all .18s ease; }
.chip-btn:hover { color: var(--accent); border-color: var(--accent); }

/* ---------------- 搜索 ---------------- */

.search {
  position: relative;
  display: flex;
  align-items: center;
  margin: 8px 0 30px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-soft);
  box-shadow: var(--shadow);
  transition: border-color .2s ease;
}
.search:focus-within { border-color: var(--accent); }

.search-ico {
  padding: 0 4px 0 16px;
  color: var(--ink-3);
  font-size: 1.15rem;
}

.search input {
  flex: 1;
  border: 0;
  outline: 0;
  background: transparent;
  padding: 14px 10px;
  font-family: var(--serif);
  font-size: .95rem;
  color: var(--ink);
}
.search input::placeholder { color: var(--ink-3); }
.search input::-webkit-search-cancel-button { display: none; }

.search-clear {
  border: 0; background: transparent; cursor: pointer;
  color: var(--ink-3); font-size: 1.3rem; padding: 0 14px; line-height: 1;
}
.search-clear:hover { color: var(--accent); }

.search-tip {
  margin: -18px 0 24px;
  font-family: var(--sans);
  font-size: .78rem;
  color: var(--ink-3);
  letter-spacing: .04em;
}

/* ---------------- 目录 ---------------- */

.part { margin: 44px 0 6px; }
.part-head {
  display: flex; align-items: baseline; gap: 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}
.part-head h2 {
  margin: 0;
  font-size: 1.15rem;
  font-weight: 500;
  letter-spacing: .3em;
}
.part-head span {
  font-family: var(--sans);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--ink-3);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 12px;
  margin-top: 18px;
}

.card {
  position: relative;
  display: block;
  padding: 16px 18px 15px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-soft);
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.card:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  box-shadow: var(--shadow);
}

.card-no {
  font-family: var(--sans);
  font-size: .68rem;
  letter-spacing: .14em;
  color: var(--ink-3);
  display: flex;
  align-items: center;
  gap: 7px;
}
.card-no::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

.card-title {
  margin: 7px 0 5px;
  font-size: 1.08rem;
  letter-spacing: .18em;
  font-weight: 500;
}
.card-first {
  font-size: .82rem;
  color: var(--ink-3);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-dot {
  position: absolute;
  top: 15px; right: 15px;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0;
  transition: opacity .2s ease;
}
.card.read .card-dot { opacity: 1; }
.card.read .card-title { color: var(--ink-2); }

.card mark { background: var(--accent-bg); color: var(--accent); border-radius: 3px; padding: 0 1px; }

.empty {
  padding: 60px 0;
  text-align: center;
  color: var(--ink-3);
  letter-spacing: .1em;
}

/* ---------------- 章节页 ---------------- */

.chapter { padding: 44px 0 8px; }

.ch-head { text-align: center; margin-bottom: 34px; }

.ch-no {
  font-family: var(--sans);
  font-size: .74rem;
  letter-spacing: .3em;
  color: var(--accent);
  margin: 0 0 10px;
}

.ch-title {
  margin: 0 0 14px;
  font-size: clamp(1.7rem, 5vw, 2.15rem);
  font-weight: 500;
  letter-spacing: .26em;
  text-indent: .26em;
}

.ch-actions { display: flex; justify-content: center; gap: 10px; margin-top: 6px; }

.act {
  font-family: var(--sans);
  font-size: .72rem;
  letter-spacing: .1em;
  padding: 5px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  color: var(--ink-3);
  cursor: pointer;
  transition: all .18s ease;
}
.act:hover { color: var(--accent); border-color: var(--accent); }
.act.on { color: var(--bg-soft); background: var(--accent); border-color: var(--accent); }

.sec { margin: 34px 0; }

.sec-head {
  display: flex; align-items: center; gap: 12px;
  margin-bottom: 16px;
}
.sec-head h3 {
  margin: 0;
  font-size: .95rem;
  font-weight: 500;
  letter-spacing: .34em;
  white-space: nowrap;
  color: var(--ink);
}
.sec-head::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}
.sec-head .seal {
  width: 22px; height: 22px;
  display: grid; place-items: center;
  border-radius: 6px;
  background: var(--accent);
  color: var(--bg-soft);
  font-size: .72rem;
  padding-bottom: 1px;
  flex: none;
}

/* 原文 */
.yuan {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 38px 34px;
  box-shadow: var(--shadow);
}
.yuan p {
  margin: 0 auto;
  font-size: 1.28rem;
  line-height: 2.5;
  letter-spacing: .1em;
  text-align: center;
  color: var(--ink);
  text-wrap: balance;
}
.yuan p + p { margin-top: 2px; }

/* 内嵌注释词条 */
.anno {
  color: var(--accent);
  border-bottom: 1px dotted var(--accent);
  cursor: help;
  border-radius: 2px;
}
.anno:hover, .anno:focus { background: var(--accent-bg); outline: none; }

.anno-pop {
  position: fixed;
  z-index: 60;
  max-width: min(340px, calc(100vw - 24px));
  padding: 11px 15px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg-soft);
  color: var(--ink-2);
  font-size: .9rem;
  line-height: 1.95;
  text-align: justify;
  box-shadow: var(--shadow);
}
.anno-pop[hidden] { display: none; }

/* 注释 */
.notes { margin: 0; }
.note {
  display: flex;
  gap: 16px;
  padding: 13px 2px;
  border-bottom: 1px dashed var(--line);
}
.note:last-child { border-bottom: 0; }
.note dt {
  flex: none;
  width: 8.5em;
  color: var(--accent);
  font-size: .95rem;
  letter-spacing: .04em;
  line-height: 1.85;
}
.note dd {
  margin: 0;
  color: var(--ink-2);
  font-size: .92rem;
  line-height: 2.05;
  text-align: justify;
}

/* 译文 / 评析 */
.prose {
  font-size: 1rem;
  line-height: 2.25;
  color: var(--ink);
  text-align: justify;
  margin: 0;
}

.review {
  border-left: 3px solid var(--accent);
  background: var(--bg-soft);
  padding: 22px 26px;
  border-radius: 0 12px 12px 0;
}
.review .prose { color: var(--ink-2); font-size: .96rem; }

/* 翻页 */
.pager {
  display: flex;
  align-items: stretch;
  gap: 12px;
  margin: 52px 0 40px;
}
.pager a, .pager span {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  padding: 15px 20px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-soft);
  transition: all .18s ease;
  min-width: 0;
}
.pager a:hover { border-color: var(--accent); background: var(--accent-bg); }
.pager .pg-label {
  font-family: var(--sans);
  font-size: .66rem;
  letter-spacing: .18em;
  color: var(--ink-3);
}
.pager .pg-title {
  font-size: .98rem;
  letter-spacing: .12em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.pager .next { text-align: right; align-items: flex-end; }
.pager .mid {
  flex: 0 0 84px;
  text-align: center;
  align-items: center;
  color: var(--ink-3);
  font-size: .85rem;
  letter-spacing: .2em;
}
.pager .disabled { opacity: .35; pointer-events: none; }

/* ---------------- 页脚 ---------------- */

.foot {
  margin: 56px 0 10px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
  text-align: center;
  color: var(--ink-3);
  font-size: .78rem;
  line-height: 2;
}
.foot p { margin: 0; }

/* ---------------- 响应式 ---------------- */

@media (max-width: 640px) {
  .wrap { padding: 0 18px; }
  .hero { padding: 40px 0 28px; }
  .grid { grid-template-columns: 1fr; }
  .yuan { padding: 28px 20px; }
  .yuan p { font-size: 1.12rem; line-height: 2.3; }
  .note { flex-direction: column; gap: 4px; }
  .note dt { width: auto; }
  .pager { flex-wrap: wrap; }
  .pager .mid { order: 3; flex: 1 0 100%; }
  .pager .next { text-align: right; }
}

@media print {
  .topbar, .pager, .ch-actions, .search, .hero-meta, .foot { display: none !important; }
  body { background: #fff; }
  .card { break-inside: avoid; }
}