.site-podcast-nav{display:flex;align-items:center;justify-content:space-between;gap:.6rem 1.5rem;flex-wrap:wrap;padding:.85rem clamp(1rem,6vw,4rem);background:rgba(255,253,247,.82);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
    .site-podcast-nav .nav-brand{font-family:Georgia,"Times New Roman","Microsoft YaHei",serif;font-weight:900;letter-spacing:.02em;color:var(--ink);font-size:1rem}
    .site-podcast-nav .nav-links{display:flex;flex-wrap:nowrap;gap:1.1rem;overflow-x:auto;min-width:0;scrollbar-width:none;-webkit-overflow-scrolling:touch}
    .site-podcast-nav .nav-links a{color:var(--muted);text-decoration:none;font-size:.9rem;font-weight:600;transition:color .15s ease;white-space:nowrap;flex:none}
    .site-podcast-nav .nav-links a:hover{color:var(--clay)}
    .site-podcast-nav .nav-links a[aria-current="page"]{color:var(--clay);font-weight:700}
    .site-podcast-nav .nav-links::-webkit-scrollbar{display:none}
    :root {
      --ink: #1e1b16;
      --muted: #655f57;
      --paper: #fbf7ef;
      --panel: #fffdf7;
      --line: #ded2bf;
      --clay: #b2573f;
      --moss: #326b55;
      --blue: #235f83;
      --gold: #b78322;
      --rose: #8f3f5b;
      --shadow: 0 18px 50px rgba(55, 43, 26, .13);
    }
    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background:
        radial-gradient(circle at top left, rgba(178,87,63,.13), transparent 34rem),
        radial-gradient(circle at 80% 10%, rgba(35,95,131,.12), transparent 32rem),
        linear-gradient(135deg, #fbf7ef 0%, #f2ecdf 48%, #edf3ef 100%);
      font-family: "Microsoft YaHei", "Noto Sans SC", "PingFang SC", sans-serif;
      line-height: 1.68;
    }
    .grain {
      position: fixed;
      inset: 0;
      pointer-events: none;
      opacity: .08;
      background-image: linear-gradient(90deg, #000 1px, transparent 1px), linear-gradient(#000 1px, transparent 1px);
      background-size: 23px 23px;
      mix-blend-mode: multiply;
    }
    header.hero {
      min-height: 88vh;
      padding: 6vw 6vw 3rem;
      display: grid;
      align-items: end;
      border-bottom: 1px solid var(--line);
      position: relative;
    }
    .hero-inner {
      max-width: 1180px;
      width: 100%;
      margin: 0 auto;
      display: grid;
      grid-template-columns: minmax(0, 1.1fr) minmax(280px, .55fr);
      gap: clamp(1.5rem, 4vw, 4rem);
      align-items: end;
    }
    .eyebrow {
      display: inline-flex;
      gap: .55rem;
      flex-wrap: wrap;
      color: var(--moss);
      font-size: .86rem;
      font-weight: 700;
      letter-spacing: 0;
      text-transform: uppercase;
    }
    h1 {
      margin: 1rem 0 1.1rem;
      font-family: Georgia, "Times New Roman", "Microsoft YaHei", serif;
      font-size: clamp(2.2rem, 6.6vw, 5.8rem);
      line-height: .98;
      letter-spacing: 0;
      max-width: 980px;
    }
    .subtitle {
      max-width: 760px;
      font-size: clamp(1rem, 2vw, 1.28rem);
      color: #3f3a33;
    }
    .player-panel {
      background: rgba(255, 253, 247, .78);
      border: 1px solid var(--line);
      padding: 1rem;
      box-shadow: var(--shadow);
      backdrop-filter: blur(12px);
    }
    audio { width: 100%; margin-top: .7rem; }
    .meta-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: .65rem;
      margin-top: 1rem;
    }
    .metric {
      border-top: 3px solid var(--gold);
      padding-top: .55rem;
      min-width: 0;
    }
    .metric b { display: block; font-size: 1.05rem; }
    .metric span { color: var(--muted); font-size: .82rem; }
    main { max-width: 1180px; margin: 0 auto; padding: 3rem 6vw 5rem; }
    section { margin: 0 0 4rem; }
    .section-head {
      display: flex;
      align-items: end;
      justify-content: space-between;
      gap: 1rem;
      border-bottom: 1px solid var(--line);
      padding-bottom: .8rem;
      margin-bottom: 1.2rem;
    }
    h2 {
      margin: 0;
      font-family: Georgia, "Times New Roman", "Microsoft YaHei", serif;
      font-size: clamp(1.7rem, 3vw, 2.65rem);
      letter-spacing: 0;
    }
    .section-note { color: var(--muted); max-width: 520px; font-size: .95rem; }
    .takeaway {
      display: grid;
      grid-template-columns: minmax(0, .85fr) minmax(260px, .45fr);
      gap: 1rem;
      align-items: stretch;
    }
    .takeaway .lead {
      background: var(--panel);
      border-left: 8px solid var(--clay);
      padding: clamp(1.2rem, 3vw, 2rem);
      box-shadow: var(--shadow);
      font-size: 1.08rem;
    }
    .takeaway aside {
      background: #183c47;
      color: #f8f0df;
      padding: 1.2rem;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .takeaway aside b { font-size: 2.3rem; font-family: Georgia, serif; }
    .chapter-grid {
      display: grid;
      grid-template-columns: repeat(4, minmax(0, 1fr));
      gap: .9rem;
    }
    .chapter-card, .idea-card, .term {
      background: rgba(255, 253, 247, .88);
      border: 1px solid var(--line);
      padding: 1rem;
      min-width: 0;
      box-shadow: 0 10px 24px rgba(62, 48, 28, .07);
    }
    .chapter-card {
      position: relative;
      overflow: hidden;
    }
    .chapter-card::before {
      content: "";
      position: absolute;
      inset: 0 0 auto;
      height: 5px;
      background: linear-gradient(90deg, var(--clay), var(--gold), var(--moss), var(--blue));
    }
    .chapter-card h3, .idea-card h3, .term h3 {
      margin: .65rem 0 .45rem;
      line-height: 1.25;
      font-size: 1.05rem;
    }
    .chapter-card p, .idea-card p, .term p {
      margin: 0;
      color: #48423b;
      font-size: .93rem;
    }
    .chapter-time { min-height: 2.1rem; }
    .timestamp {
      appearance: none;
      border: 1px solid rgba(30,27,22,.18);
      background: #f8ead0;
      color: #573218;
      font: inherit;
      font-size: .82rem;
      font-weight: 700;
      padding: .35rem .52rem;
      cursor: pointer;
      border-radius: 0;
      transition: transform .16s ease, background .16s ease, border-color .16s ease;
    }
    .timestamp:hover, .timestamp:focus-visible {
      transform: translateY(-1px);
      background: #ffe0a3;
      border-color: var(--gold);
      outline: none;
    }
    .timestamp.tiny { padding: .2rem .42rem; font-size: .78rem; }

    #learning-map {
      width: min(1540px, calc(100vw - 2rem));
      margin-left: 50%;
      transform: translateX(-50%);
    }
    .learning-map {
      display: grid;
      grid-template-columns: 330px minmax(680px, 1fr) 320px;
      gap: 1.25rem;
      align-items: start;
      min-height: 760px;
    }
    .map-rail, .map-detail, .toolbox {
      background: rgba(255, 253, 247, .9);
      border: 1px solid var(--line);
      box-shadow: 0 12px 30px rgba(62, 48, 28, .08);
      min-width: 0;
    }
    .map-rail, .toolbox {
      position: sticky;
      top: 1rem;
      max-height: calc(100vh - 2rem);
      overflow: auto;
    }
    .map-rail-head {
      padding: 1rem;
      border-bottom: 1px solid var(--line);
      background: #f6f0e5;
    }
    .map-rail-head h3, .toolbox h3 {
      margin: 0;
      font-size: 1.05rem;
      line-height: 1.25;
    }
    .map-rail-head p, .toolbox p {
      color: var(--muted);
      font-size: .86rem;
      margin: .35rem 0 0;
    }
    .map-filter-tags {
      display: flex;
      flex-wrap: wrap;
      gap: .35rem;
      margin-top: .8rem;
    }
    .map-filter-tags span, .node-tags span, .level-pill {
      border: 1px solid #cbd8e9;
      background: #f7fbff;
      color: #244b70;
      padding: .22rem .45rem;
      font-size: .75rem;
      line-height: 1.2;
      white-space: nowrap;
    }
    .map-node {
      width: 100%;
      text-align: left;
      display: grid;
      grid-template-columns: 4.6rem minmax(0, 1fr);
      gap: .55rem;
      border: 0;
      border-bottom: 1px solid var(--line);
      background: transparent;
      color: var(--ink);
      padding: .85rem .75rem;
      cursor: pointer;
      font: inherit;
    }
    .map-node:hover, .map-node.is-active {
      background: #eef5ff;
      box-shadow: inset 4px 0 0 #2367d1;
    }
    .map-node-time {
      color: #0d62d7;
      font-family: Consolas, "Courier New", monospace;
      font-size: .78rem;
      font-weight: 800;
      padding-top: .12rem;
    }
    .map-node-title {
      display: block;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: .22rem;
    }
    .map-node-range {
      color: var(--muted);
      font-size: .8rem;
    }
    .node-tags {
      display: flex;
      flex-wrap: wrap;
      gap: .28rem;
      margin-top: .46rem;
    }
    .node-tags span:first-child {
      background: #142033;
      color: #fff;
      border-color: #142033;
    }
    .map-detail {
      padding: clamp(1.2rem, 2.2vw, 2rem);
    }
    .detail-kicker {
      color: var(--blue);
      font-size: .86rem;
      font-weight: 800;
    }
    .detail-title-row {
      display: grid;
      grid-template-columns: minmax(0, 1fr) auto;
      gap: 1rem;
      align-items: start;
      margin: .25rem 0 .65rem;
    }
    .detail-title-row h3 {
      font-family: Georgia, "Times New Roman", "Microsoft YaHei", serif;
      font-size: clamp(1.65rem, 2.8vw, 2.55rem);
      line-height: 1.08;
      margin: 0;
      letter-spacing: 0;
    }
    .detail-summary {
      font-size: 1.05rem;
      color: #3e4757;
      margin: 0 0 1rem;
    }
    .detail-stats {
      display: flex;
      flex-wrap: wrap;
      gap: .5rem;
      margin-bottom: 1.1rem;
    }
    .detail-stats span {
      background: #eef2f6;
      color: #405069;
      padding: .35rem .58rem;
      font-size: .82rem;
    }
    .explain-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: .8rem;
      margin-bottom: 1rem;
    }
    .explain-card {
      border: 1px solid var(--line);
      padding: .9rem;
      background: #f7fafc;
    }
    .explain-card.warm {
      background: #fff8ea;
      border-color: #e3bd72;
    }
    .explain-card h4, .detail-block h4 {
      margin: 0 0 .45rem;
      font-size: 1rem;
    }
    .explain-card p, .detail-block p {
      margin: 0;
      color: #3c4658;
      font-size: .94rem;
    }
    .detail-block {
      border: 1px solid var(--line);
      padding: .95rem;
      margin-bottom: .85rem;
      background: rgba(255,255,255,.55);
    }
    .level-list {
      display: grid;
      gap: .38rem;
      margin-top: .3rem;
    }
    .timeline-clues {
      list-style: none;
      margin: .4rem 0 0;
      padding: 0;
      display: grid;
      gap: .35rem;
    }
    .timeline-clues li {
      display: grid;
      grid-template-columns: auto minmax(0, 1fr);
      gap: .7rem;
      align-items: start;
      padding: .42rem 0;
      border-bottom: 1px solid rgba(222,210,191,.7);
    }
    .learning-questions {
      margin: .4rem 0 0;
      color: #2f3d50;
    }
    .takeaway-strip {
      background: #1d3c49;
      color: #fff7e8;
      padding: 1rem;
      margin-top: 1rem;
      font-weight: 700;
    }
    .toolbox {
      padding: 1rem;
    }
    .toolbox-tabs {
      display: flex;
      flex-wrap: wrap;
      gap: .38rem;
      margin: .9rem 0 1rem;
    }
    .toolbox-tab {
      border: 1px solid #cfd9e7;
      background: #fff;
      color: #1e2c3f;
      padding: .42rem .62rem;
      font: inherit;
      font-size: .84rem;
      cursor: pointer;
    }
    .toolbox-tab.is-active {
      background: #142033;
      border-color: #142033;
      color: #fff;
    }
    .tool-card {
      border: 1px solid var(--line);
      background: #fffdf7;
      padding: .85rem;
      margin-bottom: .65rem;
    }
    .tool-card h4 {
      margin: 0 0 .38rem;
      font-size: .95rem;
      line-height: 1.25;
    }
    .tool-card p {
      margin: 0;
      color: #42506a;
      font-size: .88rem;
    }


    .detail-conclusion {
      background: #142033;
      color: #fff8ea;
      border-left: 7px solid var(--gold);
      padding: 1rem 1.1rem;
      margin: 1rem 0;
      font-size: 1.02rem;
      box-shadow: 0 14px 30px rgba(20, 32, 51, .14);
    }
    .detail-conclusion b {
      display: block;
      color: #ffd88a;
      margin-bottom: .35rem;
      font-size: .9rem;
    }
    .recall-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: .85rem;
      margin: 1rem 0;
    }
    .recall-card {
      border: 1px solid var(--line);
      background: rgba(255,255,255,.66);
      padding: .95rem;
      min-width: 0;
    }
    .recall-card h4 {
      margin: 0 0 .55rem;
      font-size: 1rem;
    }
    .recall-card ol, .recall-card ul {
      margin: 0;
      padding-left: 1.15rem;
      color: #354256;
      font-size: .94rem;
    }
    .recall-card li + li { margin-top: .36rem; }
    .mind-map {
      border: 1px solid #d9c6a2;
      background: linear-gradient(135deg, #fff8ea, #f7fbff);
      padding: 1rem;
      margin: 1rem 0;
    }
    .mind-map h4 {
      margin: 0 0 .8rem;
      font-size: 1rem;
    }
    .mind-map-body {
      display: grid;
      grid-template-columns: minmax(170px, .7fr) minmax(0, 1.3fr);
      gap: .8rem;
      align-items: stretch;
    }
    .mind-core {
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      min-height: 128px;
      background: #1d3c49;
      color: #fff8ea;
      padding: 1rem;
      font-weight: 900;
      line-height: 1.25;
    }
    .mind-branches {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: .55rem;
    }
    .mind-branch {
      border: 1px solid rgba(35,95,131,.28);
      background: rgba(255,255,255,.75);
      color: #26384d;
      padding: .65rem;
      font-size: .9rem;
      font-weight: 700;
    }
    .detail-stats {
      margin-bottom: .6rem;
    }

    .idea-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 1rem;
    }
    .idea-card:nth-child(2n) { border-top: 6px solid var(--moss); }
    .idea-card:nth-child(2n+1) { border-top: 6px solid var(--blue); }
    .idea-card:nth-child(3n) { border-top-color: var(--rose); }
    .idea-tag {
      display: inline-block;
      color: #fff;
      background: var(--ink);
      padding: .2rem .48rem;
      font-size: .76rem;
      font-weight: 700;
    }
    .chip-row { display: flex; flex-wrap: wrap; gap: .45rem; margin-top: .8rem; }
    .best-list {
      list-style: none;
      padding: 0;
      margin: 0;
      display: grid;
      gap: .7rem;
    }
    .best-list li {
      display: grid;
      grid-template-columns: auto minmax(0, 1fr);
      gap: .8rem;
      align-items: start;
      padding: .85rem;
      background: rgba(255,255,255,.58);
      border-bottom: 1px solid var(--line);
    }
    .term-grid {
      display: grid;
      grid-template-columns: repeat(4, minmax(0, 1fr));
      gap: .8rem;
    }
    .caveats {
      background: #f2e7d5;
      border: 1px solid var(--line);
      padding: 1rem 1.2rem;
    }
    .transcript-tools {
      display: flex;
      gap: .7rem;
      flex-wrap: wrap;
      margin-bottom: .8rem;
    }
    .filter {
      flex: 1 1 260px;
      border: 1px solid var(--line);
      padding: .7rem .8rem;
      background: var(--panel);
      color: var(--ink);
      font: inherit;
    }
    .transcript-block {
      background: rgba(255, 255, 255, 0.65);
      border: 1px solid var(--line);
      border-radius: 8px;
      margin-bottom: .6rem;
      overflow: hidden;
      box-shadow: 0 2px 8px rgba(15, 23, 42, 0.01);
    }
    .transcript-block summary {
      cursor: pointer;
      padding: .9rem 1.25rem;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1.5rem;
      font-weight: 700;
      color: var(--clay);
      transition: background 0.15s ease;
    }
    .transcript-block summary:hover {
      background: #f8fafc;
    }
    .transcript-block p {
      margin: 0;
      padding: 0 1.25rem 1.1rem;
      color: #4a4238;
      font-size: .95rem;
      line-height: 1.7;
      border-top: 1px dashed rgba(203, 213, 225, 0.6);
      padding-top: 0.8rem;
    }
    .transcript-block .seg-body {
      padding: .2rem 1.25rem 1.1rem;
      border-top: 1px dashed rgba(203, 213, 225, 0.6);
      color: #40382f;
    }
    .transcript-block .seg-body p {
      margin: 0;
      padding: 0;
      border: 0;
    }
    .seg-summary {
      line-height: 1.7;
      font-size: .96rem;
    }
    .seg-points-title {
      margin-top: .75rem !important;
      font-weight: 800;
      color: var(--clay);
      font-size: .9rem;
    }
    .seg-points {
      margin: .45rem 0 0;
      padding-left: 1.15rem;
      line-height: 1.65;
      color: #51483f;
      font-size: .92rem;
    }
    .seg-quote {
      margin: .8rem 0 0;
      padding: .7rem .85rem;
      background: rgba(248, 234, 208, .52);
      border-left: 4px solid var(--gold);
      color: #4b3623;
      font-size: .9rem;
      line-height: 1.65;
    }
    .tool-btn {
      appearance: none;
      background: #f1f5f9;
      color: #4a4238;
      border: 1px solid #cbd5e1;
      padding: .6rem 1rem;
      font: inherit;
      font-size: .88rem;
      font-weight: 600;
      cursor: pointer;
      border-radius: 6px;
      transition: all 0.15s ease;
    }
    .tool-btn:hover {
      background: #e2e8f0;
      color: var(--ink);
    }
    .tool-btn.primary {
      background: var(--ink);
      color: #fff;
      border-color: var(--ink);
    }
    .tool-btn.primary:hover {
      background: #1e293b;
    }
    .timestamp.play-btn {
      appearance: none;
      border: 1px solid rgba(79, 70, 229, 0.15);
      background: #e0e7ff;
      color: #3730a3;
      font: inherit;
      font-size: .84rem;
      font-weight: 700;
      padding: .4rem .6rem;
      cursor: pointer;
      border-radius: 6px;
      transition: all .16s ease;
    }
    .timestamp.play-btn:hover {
      background: #c7d2fe;
      border-color: var(--clay);
      outline: none;
    }
    .transcript-block-title {
      flex: 1 1 auto;
      font-size: 0.98rem;
      color: var(--ink);
    }
    footer {
      margin-top: 4rem;
      padding-top: 1.2rem;
      border-top: 1px solid var(--line);
      color: var(--muted);
      font-size: .86rem;
      word-break: break-word;
    }
    @media (max-width: 980px) {
      .hero-inner, .takeaway { grid-template-columns: 1fr; }
      #learning-map { width: auto; margin-left: 0; transform: none; }
      .learning-map { grid-template-columns: 1fr; }
      .map-rail, .toolbox { position: static; max-height: none; }
      .chapter-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
      .idea-grid, .term-grid { grid-template-columns: 1fr 1fr; }
      header.hero { min-height: auto; }
    }
    @media (max-width: 640px) {
      main, header.hero { padding-left: 1rem; padding-right: 1rem; }
      .chapter-grid, .idea-grid, .term-grid, .meta-grid, .explain-grid, .recall-grid, .mind-map-body, .mind-branches { grid-template-columns: 1fr; }
      .map-node { grid-template-columns: 4rem minmax(0, 1fr); }
      .detail-title-row { grid-template-columns: 1fr; }
      .section-head { display: block; }
      .best-list li { grid-template-columns: 1fr; }
      h1 { font-size: clamp(2rem, 13vw, 3.7rem); }
    }