/* 吠树精读库 — 书斋设计系统（与 bigthink-agy2c 同源） */
:root {
  --paper: #F7F6F2;
  --paper-deep: #EFEEE7;
  --card: #FCFBF8;
  --ink: #21313A;
  --ink-soft: #5C6B74;
  --ink-faint: #8A949B;
  --hairline: #E1DED3;
  --indigo: #3A6285;
  --indigo-deep: #2C4E6B;
  --seal: #B23B2E;
  --cat: var(--seal);
  --serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", sans-serif;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.9;
}
a { color: var(--indigo); text-decoration: none; }
a:hover { color: var(--indigo-deep); text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--seal); outline-offset: 2px; border-radius: 2px; }
::selection { background: #E8D8C8; }

/* ---------- 页首（吸顶单行） ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(247,246,242,.94);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--hairline);
}
.site-header .bar {
  max-width: 1120px;
  margin: 0 auto;
  padding: 10px 28px;
  display: flex; align-items: center; gap: 14px;
}
.brand { display: flex; align-items: center; gap: 11px; color: var(--ink); flex: none; }
.brand:hover { text-decoration: none; }
.seal {
  width: 36px; height: 36px;
  background: var(--seal);
  color: #F7F6F2;
  font-weight: 700;
  font-size: 19px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 3px;
  box-shadow: inset 0 0 0 2px rgba(247,246,242,.35), inset 0 0 0 4px var(--seal);
  flex: none;
}
.brand-name { font-size: 16px; font-weight: 700; letter-spacing: .04em; line-height: 1.25; display: block; }
.brand-sub { font-family: var(--sans); font-size: 10.5px; color: var(--ink-faint); letter-spacing: .02em; display: block; }
.site-nav {
  display: flex; align-items: center; gap: 1px;
  font-family: var(--sans); font-size: 13.5px;
  min-width: 0;
}
.site-nav a {
  color: var(--ink-soft);
  padding: 6px 9px; border-radius: 4px;
  white-space: nowrap;
  display: inline-flex; align-items: center; gap: 6px;
}
.site-nav a .dot { width: 7px; height: 7px; border-radius: 2px; background: var(--c); opacity: .5; flex: none; }
.site-nav a:hover { color: var(--ink); background: var(--paper-deep); text-decoration: none; }
.site-nav a:hover .dot { opacity: .9; }
.site-nav a.active { color: var(--c); font-weight: 700; background: var(--paper-deep); }
.site-nav a.active .dot { opacity: 1; }
.site-nav .nav-search { color: var(--seal); display: none; }
.site-nav .nav-search::before { content: "⌕ "; font-weight: 700; }

/* 页头即时搜索 */
.hdr-search { position: relative; margin-left: auto; width: 230px; flex: none; transition: width .25s ease; }
.hdr-search:focus-within { width: 320px; }
#q {
  width: 100%; height: 34px;
  padding: 0 14px 0 32px;
  border: 1px solid var(--hairline); border-radius: 999px;
  background: var(--card) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%238A949B' stroke-width='2.4' stroke-linecap='round'%3E%3Ccircle cx='11' cy='11' r='7'/%3E%3Cpath d='M20 20l-4-4'/%3E%3C/svg%3E") 11px center/13px no-repeat;
  font-family: var(--sans); font-size: 13.5px; color: var(--ink);
  outline: none;
}
#q::placeholder { color: var(--ink-faint); }
#q:focus { border-color: var(--seal); box-shadow: 0 0 0 3px rgba(178,59,46,.10); }
.qr {
  position: absolute; top: calc(100% + 8px); right: 0;
  width: min(520px, 92vw); max-height: 62vh; overflow: auto;
  background: var(--card);
  border: 1px solid var(--hairline); border-radius: 10px;
  box-shadow: 0 14px 40px rgba(33,49,58,.16);
  display: none;
}
.qr.open { display: block; }
.qr-item { display: block; padding: 10px 16px; border-bottom: 1px solid var(--hairline); }
.qr-item:hover, .qr-item.sel { background: var(--paper-deep); text-decoration: none; }
.qr-cat { display: flex; align-items: center; gap: 6px; font-family: var(--sans); font-size: 12px; color: var(--ink-faint); margin-bottom: 2px; }
.qr-cat i { width: 6px; height: 6px; border-radius: 2px; flex: none; }
.qr-t { display: block; font-family: var(--serif); font-size: 14.5px; font-weight: 600; line-height: 1.6; color: var(--ink); }
.qr-t mark { background: #F3E3C9; color: inherit; padding: 0 1px; }
.qr-foot { display: block; padding: 11px 16px; font-family: var(--sans); font-size: 13px; color: var(--seal); text-align: center; }
.qr-foot:hover { background: var(--paper-deep); text-decoration: none; color: var(--seal); }
.qr-empty { padding: 20px 16px; font-family: var(--sans); font-size: 13.5px; color: var(--ink-faint); text-align: center; }

/* ---------- 首页 ---------- */
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 28px; }
.hero { padding: 62px 0 52px; }
.hero h1 {
  font-size: clamp(38px, 6vw, 62px);
  font-weight: 900;
  letter-spacing: .02em;
  line-height: 1.24;
  margin: 0 0 22px;
}
.hero .hero-line { font-size: 19px; color: var(--ink-soft); max-width: 38em; margin: 0 0 10px; }
.hero .hero-stats { font-family: var(--sans); font-size: 14px; color: var(--ink-faint); margin-top: 24px; }
.hero-rule { width: 56px; height: 4px; background: var(--seal); margin-top: 32px; border-radius: 1px; }

.dir-head { display: flex; align-items: baseline; gap: 16px; margin-bottom: 6px; }
.dir-head h2 { font-size: 22px; font-weight: 700; margin: 0; letter-spacing: .03em; }
.dir-head .muted { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); }
.dir { border-top: 1px solid var(--hairline); }
.dir-row {
  border-bottom: 1px solid var(--hairline);
  padding: 30px 0 32px;
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 12px 48px;
}
.dir-cat { display: flex; flex-direction: column; gap: 8px; }
.dir-cat-name { display: flex; align-items: baseline; gap: 12px; }
.dir-cat-name .dot { width: 10px; height: 10px; border-radius: 2px; flex: none; transform: translateY(-1px); }
.dir-cat-name a { font-size: 25px; font-weight: 900; color: var(--ink); letter-spacing: .04em; }
.dir-cat-name a:hover { color: var(--indigo-deep); text-decoration: none; }
.dir-cat-en { font-family: var(--sans); font-size: 12.5px; color: var(--ink-faint); letter-spacing: .05em; }
.dir-cat-desc { font-size: 15px; color: var(--ink-soft); line-height: 1.8; }
.dir-cat-count { font-family: var(--sans); font-size: 13px; color: var(--ink-soft); }
.dir-cat-count b { color: var(--ink); font-size: 15px; }
.dir-right { display: flex; flex-direction: column; gap: 12px; padding-top: 4px; }
.dir-samples { display: flex; flex-direction: column; }
.dir-samples a {
  font-size: 15.5px; font-weight: 600; color: var(--ink);
  padding: 7px 0; line-height: 1.65;
  display: flex; align-items: baseline; gap: 10px;
}
.dir-samples a::before { content: ""; width: 5px; height: 5px; background: var(--ink-faint); border-radius: 1px; flex: none; transform: translateY(-2px); }
.dir-samples a:hover { color: var(--indigo-deep); text-decoration: none; }
.dir-all { font-family: var(--sans); font-size: 13.5px; color: var(--ink-soft); }
.dir-all:hover { color: var(--indigo-deep); }

/* ---------- 面包屑 / 分类页 ---------- */
.crumbs { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); padding: 30px 0 0; }
.crumbs a { color: var(--ink-soft); }
.crumbs a:hover { color: var(--ink); }
.crumbs span.sep { margin: 0 8px; color: var(--hairline); }
.page-head { padding: 40px 0 30px; }
.page-head h1 { font-size: clamp(30px, 4.4vw, 44px); font-weight: 900; margin: 0 0 14px; letter-spacing: .03em; }
.page-head .en { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); letter-spacing: .08em; display: flex; align-items: center; gap: 8px; }
.page-head .en i { font-style: normal; width: 10px; height: 10px; border-radius: 2px; background: var(--cat); }
.page-head .desc { font-size: 17px; color: var(--ink-soft); max-width: 34em; margin: 12px 0 8px; }
.page-head .count { font-family: var(--sans); font-size: 13.5px; color: var(--ink-faint); }
.page-head .count code { font-family: var(--sans); background: var(--paper-deep); padding: 1px 6px; border-radius: 4px; }
.page-head .rule { width: 56px; height: 3px; background: var(--cat); border-radius: 1px; margin-top: 22px; }

.cat-list {
  list-style: none;
  margin: 0; padding: 34px 0 20px;
  columns: 2; column-gap: 56px;
  border-top: 1px solid var(--hairline);
}
.cat-list li { break-inside: avoid; }
.cat-list a {
  display: block;
  padding: 8px 2px;
  border-bottom: 1px solid var(--hairline);
  font-size: 15px; font-weight: 600; color: var(--ink);
  line-height: 1.7;
}
.cat-list a:hover { color: var(--indigo-deep); text-decoration: none; background: var(--card); }

/* ---------- 文章页 ---------- */
.article-shell {
  max-width: 1120px; margin: 0 auto;
  padding: 0 28px;
  display: grid;
  grid-template-columns: 76px minmax(0, 760px);
  justify-content: center;
  gap: 56px;
}
.spine {
  position: sticky; top: 86px;
  height: fit-content;
  padding-top: 90px;
  display: flex; flex-direction: column; align-items: center; gap: 14px;
  font-family: var(--sans);
}
.spine .spine-color { width: 3px; height: 84px; border-radius: 2px; background: var(--cat); }
.spine .spine-text { writing-mode: vertical-rl; font-size: 14px; letter-spacing: .34em; color: var(--ink-soft); }
.spine .spine-count { writing-mode: vertical-rl; font-size: 11px; color: var(--ink-faint); letter-spacing: .2em; font-variant-numeric: tabular-nums; }

.article { padding: 46px 0 40px; }
.article > header { margin-bottom: 30px; }
.article h1 {
  font-size: clamp(27px, 4vw, 38px);
  font-weight: 900;
  line-height: 1.45;
  letter-spacing: .015em;
  margin: 0 0 18px;
}
.article .meta { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); display: flex; align-items: center; gap: 10px; }
.article .meta .m-dot { width: 7px; height: 7px; border-radius: 2px; background: var(--cat); flex: none; }

.article-body { font-size: 17px; }
.article-body p { margin: 1.1em 0; }
.article-body h2 { font-size: 24px; font-weight: 800; letter-spacing: .02em; margin: 2.4em 0 .8em; line-height: 1.5; }
.article-body h3 { font-size: 19px; font-weight: 700; margin: 2em 0 .6em; }

/* 三段式小节标题：核心要点 / 行动指南 */
.article-body h2.sec {
  display: flex; align-items: center; gap: 12px;
  font-family: var(--sans);
  font-size: 14.5px; font-weight: 700;
  letter-spacing: .3em; text-indent: .3em; /* 抵消末字间距 */
  color: var(--ink-soft);
  margin: 2.8em 0 1.1em;
}
.article-body h2.sec::before { content: ""; width: 9px; height: 9px; border-radius: 2px; background: var(--cat); flex: none; }
.article-body h2.sec::after { content: ""; flex: 1; height: 1px; background: var(--hairline); }

.article-body ul { list-style: none; padding-left: 1.35em; margin: 1em 0; }
.article-body ul > li { position: relative; margin: .55em 0; }
.article-body ul > li::before {
  content: ""; position: absolute; left: -1em; top: .78em;
  width: 5px; height: 5px; background: var(--ink-faint); border-radius: 1px;
}
.article-body ol { padding-left: 1.6em; margin: 1em 0; }
.article-body ol > li { margin: .55em 0; }
.article-body li::marker { color: var(--ink-faint); }
.article-body li > strong:first-child { color: var(--ink); }
.article-body li > p { margin: .4em 0; }
.article-body strong { font-weight: 700; }
.article-body img { max-width: 100%; }
.article-body code { font-family: "SF Mono", Menlo, Consolas, monospace; font-size: .86em; background: var(--paper-deep); padding: 2px 6px; border-radius: 4px; }
.article-body pre { background: var(--paper-deep); padding: 18px 20px; border-radius: 6px; overflow-x: auto; }
.article-body pre code { background: none; padding: 0; }
.article-body table { border-collapse: collapse; width: 100%; margin: 1.6em 0; font-size: 15.5px; }
.article-body th, .article-body td { border: 1px solid var(--hairline); padding: 9px 13px; text-align: left; }
.article-body th { background: var(--paper-deep); font-weight: 700; }

/* 兜底 blockquote（非一句话总结位置） */
.article-body blockquote {
  margin: 1.6em 0;
  padding: 2px 0 2px 22px;
  border-left: 3px solid var(--hairline);
  color: var(--ink-soft);
}

/* 一句话总结卡片 */
.takeaway {
  margin: 3.2em 0 .6em;
  padding: 26px 30px 28px;
  background: var(--card);
  border: 1px solid var(--hairline);
  border-left: 3px solid var(--seal);
  border-radius: 0 6px 6px 0;
}
.takeaway .tk-k {
  font-family: var(--sans); font-size: 12px; font-weight: 700;
  letter-spacing: .32em; color: var(--seal);
  margin-bottom: 12px;
}
.takeaway blockquote { border: none; margin: 0; padding: 0; color: var(--ink); }
.takeaway blockquote p { margin: 0; font-size: 18.5px; font-weight: 600; line-height: 2; }

.article-foot { margin-top: 52px; border-top: 1px solid var(--hairline); padding-top: 26px; }
.origin-line { font-family: var(--sans); font-size: 13.5px; color: var(--ink-soft); margin: 0 0 34px; }
.pn { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.pn a { display: block; color: inherit; }
.pn a:hover { text-decoration: none; }
.pn .pn-k { font-family: var(--sans); font-size: 12px; color: var(--ink-faint); display: block; margin-bottom: 6px; }
.pn .pn-t { font-size: 16px; font-weight: 600; color: var(--ink); line-height: 1.6; }
.pn a:hover .pn-t { color: var(--indigo-deep); }
.pn .next { text-align: right; }

/* ---------- 搜索页 ---------- */
.search-head { padding: 54px 0 30px; max-width: 780px; }
.search-head h1 { font-size: 32px; font-weight: 900; margin: 0 0 24px; }
#search-input {
  width: 100%;
  font-family: var(--serif); font-size: 18px;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  padding: 14px 18px;
}
#search-input:focus { outline: none; border-color: var(--seal); box-shadow: 0 0 0 3px rgba(178,59,46,.12); }
#search-status { font-family: var(--sans); font-size: 13.5px; color: var(--ink-faint); margin: 18px 0 0; min-height: 1em; }
#search-results { margin-top: 10px; }
.sr-item { border-bottom: 1px solid var(--hairline); padding: 16px 0; }
.sr-item .sr-meta { font-family: var(--sans); font-size: 12.5px; color: var(--ink-faint); margin-bottom: 3px; display: flex; align-items: center; gap: 6px; }
.sr-item .sr-meta .sr-dot { width: 6px; height: 6px; border-radius: 2px; display: inline-block; }
.sr-item .sr-title { font-size: 17px; font-weight: 700; }
.sr-item .sr-title mark { background: #F3E3C9; color: inherit; padding: 0 1px; }
.sr-more { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); }

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--hairline);
  margin-top: 90px;
  padding: 34px 28px 46px;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-faint);
  text-align: center;
  line-height: 2;
}
.site-footer a { color: var(--ink-soft); }
.site-footer code { background: var(--paper-deep); padding: 1px 6px; border-radius: 4px; }

/* ---------- 404 ---------- */
.lost { text-align: center; padding: 120px 0 60px; }
.lost .seal { margin: 0 auto 30px; width: 44px; height: 44px; font-size: 24px; }
.lost h1 { font-size: 34px; font-weight: 900; margin: 0 0 14px; }
.lost p { color: var(--ink-soft); }

/* ---------- 动效 ---------- */
@media (prefers-reduced-motion: no-preference) {
  .hero, .page-head, .article > header { animation: rise .55s ease both; }
  @keyframes rise {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: none; }
  }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1020px) {
  .hdr-search { display: none; }
  .site-nav .nav-search { display: inline-flex; }
  .site-header .bar { flex-wrap: wrap; gap: 4px 10px; padding: 10px 20px; }
  .site-nav {
    order: 3; flex-basis: 100%;
    overflow-x: auto; -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    margin: 0 -20px; padding: 0 20px 4px;
  }
  .site-nav::-webkit-scrollbar { display: none; }
  .spine { top: 96px; }
}
@media (max-width: 900px) {
  .dir-row { grid-template-columns: 1fr; gap: 16px; }
}
@media (max-width: 760px) {
  body { font-size: 16.5px; }
  .wrap, .article-shell { padding-left: 20px; padding-right: 20px; }
  .spine { display: none; }
  .article-shell { grid-template-columns: minmax(0, 1fr); }
  .article { padding-top: 26px; }
  .hero { padding: 40px 0 36px; }
  .cat-list { columns: 1; }
  .pn { grid-template-columns: 1fr; gap: 22px; }
  .pn .next { text-align: left; }
  .takeaway { padding: 20px 22px 22px; }
  .takeaway blockquote p { font-size: 17px; }
  .search-head { padding-top: 34px; }
}
@media (max-width: 520px) {
  .brand-sub { display: none; }
  .brand-name { font-size: 15px; }
  .seal { width: 32px; height: 32px; font-size: 17px; }
}