/* 教材讲解本
   青格稿纸 × 朱砂批注
   浅色书桌，不是考场 */

:root {
  --paper: #dfeadf;
  --sheet: #eef4ec;
  --sheet-2: #e4eee3;
  --ink: #142018;
  --read: #243028;
  --mute: #4d5f52;
  --faint: #6e8273;
  --rule: #9bb59d;
  --rule-soft: rgba(36, 78, 52, 0.14);
  --cell: #f7fbf6;
  --cinnabar: #b1321f;
  --cinnabar-ink: #8c2416;
  --cinnabar-soft: rgba(177, 50, 31, 0.12);
  --cinnabar-line: rgba(177, 50, 31, 0.38);
  --ok: #1f6b45;
  --ok-soft: rgba(31, 107, 69, 0.12);
  --top-h: 58px;
  --rail-w: 196px;
  --measure: 40rem;
  --serif: "Noto Serif CJK SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: "Noto Sans CJK SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "Noto Sans Mono CJK SC", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

* { box-sizing: border-box; }

html {
  color-scheme: light;
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  background:
    linear-gradient(180deg, rgba(223, 234, 223, 0.92), rgba(223, 234, 223, 0.92)),
    repeating-linear-gradient(
      90deg,
      transparent 0 27px,
      rgba(36, 78, 52, 0.045) 27px 28px
    );
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--cinnabar-soft);
  color: var(--cinnabar-ink);
}

:focus-visible {
  outline: 2px solid var(--cinnabar);
  outline-offset: 3px;
}

a { color: var(--cinnabar-ink); text-underline-offset: 3px; }
a:hover { color: var(--cinnabar); }

.mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }

/* ---------- topbar ---------- */
.topbar {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--top-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 22px;
  background: var(--paper);
  border-bottom: 1px solid var(--rule-soft);
  z-index: 40;
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
}
.brand-seal {
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border: 1.5px solid var(--cinnabar);
  color: var(--cinnabar);
  font-family: var(--serif);
  font-size: 12px;
  letter-spacing: 0.08em;
  transform: rotate(-8deg);
}
.brand-name {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
}
.brand-sub {
  font-size: 12px;
  color: var(--faint);
}
.top-nav {
  display: flex;
  gap: 6px;
  align-items: center;
}
.top-nav a {
  text-decoration: none;
  color: var(--mute);
  padding: 6px 12px;
  font-size: 14px;
}
.top-nav a:hover,
.top-nav a.is-on { color: var(--ink); }
.progress {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 2px;
  background: transparent;
}
.progress i {
  display: block;
  height: 100%;
  width: 0;
  background: var(--cinnabar);
}

/* ---------- layout ---------- */
.page-index main {
  max-width: 920px;
  margin: 0 auto;
  padding: calc(var(--top-h) + 28px) 28px 80px;
}
.page-ch main {
  margin-left: var(--rail-w);
  padding: calc(var(--top-h) + 8px) 0 96px;
}
.article {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 36px;
}

/* ---------- rail ---------- */
.rail {
  position: fixed;
  top: var(--top-h);
  left: 0;
  bottom: 0;
  width: var(--rail-w);
  padding: 28px 18px 24px 22px;
  overflow: auto;
  border-right: 1px solid var(--rule-soft);
}
.rail-k {
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--faint);
  margin: 0 0 12px;
}
.rail ol {
  list-style: none;
  margin: 0;
  padding: 0;
}
.rail a {
  display: grid;
  grid-template-columns: 2.2em 1fr;
  gap: 6px;
  text-decoration: none;
  color: var(--mute);
  font-size: 13.5px;
  line-height: 1.45;
  padding: 7px 0;
}
.rail a b {
  font-family: var(--mono);
  font-weight: 500;
  color: var(--faint);
  font-size: 12px;
}
.rail a.is-on,
.rail a:hover { color: var(--ink); }
.rail a.is-on b { color: var(--cinnabar); }
.rail-foot {
  margin-top: 28px;
  font-size: 12.5px;
  color: var(--faint);
  line-height: 1.55;
}

/* ---------- cover ---------- */
.cover {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
  padding: 36px 0 48px;
}
.cover h1 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(32px, 4.4vw, 46px);
  line-height: 1.28;
  letter-spacing: 0.02em;
  margin: 0 0 18px;
}
.cover-author {
  margin: 0 0 22px;
  color: var(--mute);
  font-size: 16px;
}
.cover-lead {
  margin: 0 0 28px;
  max-width: 36ch;
  color: var(--read);
  font-size: 17.5px;
}
.cover-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: center;
}
.cover-note {
  margin: 18px 0 0;
  font-size: 13.5px;
  color: var(--faint);
}

.teaser {
  background: var(--cell);
  border: 1px solid var(--rule);
  padding: 22px 20px 18px;
  box-shadow: 0 18px 40px -28px rgba(20, 40, 28, 0.45);
}
.teaser-rule {
  height: 1px;
  background: var(--cinnabar);
  margin-bottom: 16px;
  opacity: 0.55;
}
.teaser p {
  margin: 0 0 14px;
  font-size: 13px;
  color: var(--mute);
}
.teaser-line {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}
.teaser-caption {
  display: block;
  margin: 14px 0 0;
  font-size: 13px;
  color: var(--faint);
  max-width: 28em;
}

/* ---------- toc ---------- */
.toc {
  padding: 12px 0 40px;
}
.toc > h2 {
  font-family: var(--serif);
  font-size: 28px;
  font-weight: 600;
  margin: 0 0 8px;
}
.toc-lead {
  margin: 0 0 36px;
  color: var(--mute);
  max-width: 46ch;
}
.part {
  margin: 0 0 40px;
}
.part-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin: 0 0 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule-soft);
}
.part-num {
  font-family: var(--serif);
  font-size: 22px;
  color: var(--cinnabar);
  min-width: 1.6em;
}
.part-head h3 {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  margin: 0;
}
.part-head small {
  margin-left: auto;
  color: var(--faint);
  font-size: 13px;
}
.toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.toc-list li {
  display: grid;
  grid-template-columns: 2.4em 1fr auto auto;
  gap: 10px;
  align-items: baseline;
  padding: 9px 0;
  border-bottom: 1px dotted rgba(36, 78, 52, 0.18);
  color: var(--faint);
}
.toc-list .ch-no {
  font-family: var(--mono);
  font-size: 13px;
}
.toc-list .ch-title { color: inherit; }
.toc-list .ch-page {
  font-family: var(--mono);
  font-size: 12.5px;
}
.toc-list .ch-state {
  font-size: 12px;
  min-width: 3.5em;
  text-align: right;
}
.toc-list a.live {
  display: contents;
  text-decoration: none;
  color: var(--ink);
}
.toc-list a.live .ch-title {
  color: var(--ink);
  font-weight: 600;
}
.toc-list a.live .ch-state {
  color: var(--cinnabar);
}
.toc-list li.is-off {
  cursor: default;
}

/* ---------- buttons ---------- */
.btn {
  appearance: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--sheet);
  font-family: inherit;
  font-size: 14.5px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 2px;
  transition: transform 0.18s var(--ease), background 0.18s, color 0.18s;
}
.btn:hover { background: #0c1410; color: var(--sheet); transform: translateY(-1px); }
.btn:active { transform: translateY(1px); }
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule);
}
.btn-ghost:hover { background: var(--sheet); color: var(--ink); }
.btn:disabled {
  cursor: default;
  opacity: 0.4;
  transform: none;
}
.btn-sm { padding: 8px 14px; font-size: 13.5px; }

/* ---------- chapter prose ---------- */
.ch-hero {
  padding: 36px 0 8px;
}
.ch-hero h1 {
  font-family: var(--serif);
  font-size: clamp(32px, 4.4vw, 44px);
  font-weight: 600;
  letter-spacing: 0.03em;
  line-height: 1.25;
  margin: 0 0 16px;
}
.lead {
  font-size: 18.5px;
  line-height: 1.7;
  color: var(--read);
  margin: 0 0 22px;
  max-width: 36em;
}
.intuitions {
  display: grid;
  gap: 10px;
  margin: 0 0 8px;
  padding: 0;
  list-style: none;
}
.intuitions li {
  display: grid;
  grid-template-columns: 1.6em minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  font-size: 16.5px;
}
.intuitions li span { min-width: 0; }
.intuitions i {
  font-family: var(--serif);
  font-style: normal;
  color: var(--cinnabar);
}

section.sec {
  padding: 56px 0 8px;
}
.sec h2 {
  font-family: var(--serif);
  font-size: 28px;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin: 0 0 14px;
}
.sec h3 {
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 600;
  margin: 28px 0 10px;
}
.sec p { margin: 0 0 14px; color: var(--read); max-width: 40em; }
.sec p.tight { max-width: none; }

.cite {
  font-size: 12.5px;
  color: var(--faint);
  margin: 0 0 18px;
}

.note {
  margin: 18px 0 8px;
  padding: 14px 0 2px;
  border-top: 1px solid var(--rule-soft);
  color: var(--mute);
  font-size: 15.5px;
}
.note b {
  display: block;
  font-family: var(--serif);
  color: var(--ink);
  font-weight: 600;
  margin-bottom: 4px;
}

.q-list {
  list-style: none;
  margin: 8px 0 16px;
  padding: 0;
  display: grid;
  gap: 8px;
}
.q-list li {
  display: grid;
  grid-template-columns: 5.5em 1fr;
  gap: 12px;
  padding: 8px 0;
  border-bottom: 1px dotted rgba(36, 78, 52, 0.18);
  font-size: 15.5px;
}
.q-list b {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 12.5px;
  color: var(--cinnabar);
  padding-top: 3px;
}

/* ---------- demo stage ---------- */
.demo {
  margin: 22px 0 8px;
  background: var(--cell);
  border: 1px solid var(--rule);
}
.demo-head {
  padding: 16px 18px 12px;
  border-bottom: 1px solid var(--rule-soft);
}
.demo-head h3 {
  font-family: var(--serif);
  font-size: 18px;
  margin: 0 0 4px;
}
.demo-head p {
  margin: 0;
  font-size: 14px;
  color: var(--mute);
}
.demo-body { padding: 18px; }
.demo-foot {
  padding: 0 18px 16px;
  font-size: 13.5px;
  color: var(--mute);
}

.ctl-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin: 0 0 14px;
}
.ctl-row label {
  font-size: 14px;
  color: var(--mute);
  min-width: 6.5em;
}
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  height: 3px;
  flex: 1;
  min-width: 140px;
  background: var(--rule);
  border-radius: 99px;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--cinnabar);
  border: 2px solid var(--cell);
  box-shadow: 0 0 0 1px var(--cinnabar);
}
input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--cinnabar);
  border: 2px solid var(--cell);
}

/* 田字格 */
.cells {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
}
.cell {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  position: relative;
  font-family: var(--serif);
  font-size: 22px;
  background:
    linear-gradient(var(--rule-soft), var(--rule-soft)) center / 1px 70% no-repeat,
    linear-gradient(var(--rule-soft), var(--rule-soft)) center / 70% 1px no-repeat,
    var(--sheet);
  border: 1px solid var(--rule);
  color: var(--ink);
}
.cell.is-empty,
.cell.is-wait {
  color: transparent;
  background-image: none;
  background-color: var(--cell);
}
.cell.is-prompt { background-color: #e7f0e6; }
.cell.is-next {
  color: var(--cinnabar);
  border-color: var(--cinnabar);
  background-color: #f8ece8;
}
.cell.is-wait {
  border-style: dashed;
}
.cell.is-target {
  color: var(--cinnabar);
  border-color: var(--cinnabar-line);
}
.cell.is-pop {
  animation: pop-in 0.38s var(--ease);
}
@keyframes pop-in {
  from { transform: translateY(8px); opacity: 0; filter: blur(4px); }
  to { transform: none; opacity: 1; filter: none; }
}

/* NTP */
.ntp-flow {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 12px;
  align-items: stretch;
  margin-bottom: 16px;
}
.ntp-box {
  border: 1px solid var(--rule);
  padding: 12px;
  min-height: 92px;
  background: var(--sheet);
}
.ntp-box .k {
  display: block;
  font-size: 12px;
  color: var(--faint);
  margin-bottom: 8px;
}
.ntp-mid {
  display: grid;
  place-items: center;
  min-width: 88px;
  padding: 8px;
  background: var(--ink);
  color: var(--sheet);
  font-family: var(--serif);
  letter-spacing: 0.12em;
  font-size: 15px;
}
.ntp-out .big {
  font-family: var(--serif);
  font-size: 36px;
  color: var(--cinnabar);
  line-height: 1;
  min-height: 44px;
}
.ntp-status {
  font-size: 14px;
  color: var(--mute);
  margin: 4px 0 12px;
}

/* self-sup */
.window {
  margin: 4px 0 16px;
}
.window-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}
.window-row .k {
  width: 4.2em;
  font-size: 12.5px;
  color: var(--faint);
  flex: none;
}
.pairs {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}
.pairs th {
  text-align: left;
  font-weight: 600;
  font-size: 12.5px;
  color: var(--faint);
  padding: 6px 8px;
  border-bottom: 1px solid var(--rule);
}
.pairs td {
  padding: 7px 8px;
  border-bottom: 1px dotted rgba(36, 78, 52, 0.16);
  font-family: var(--serif);
  font-size: 18px;
}
.pairs td.arrow {
  color: var(--faint);
  font-family: var(--sans);
  font-size: 13px;
  width: 2.4em;
}
.pairs td.tgt { color: var(--cinnabar); }

/* xent */
.xent-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 22px;
  align-items: start;
}
.bars { display: grid; gap: 8px; }
.bar-row {
  display: grid;
  grid-template-columns: 1.6em 1fr 3.6em;
  gap: 8px;
  align-items: center;
  font-size: 14px;
}
.bar-track {
  height: 10px;
  background: var(--sheet-2);
  border: 1px solid var(--rule-soft);
}
.bar-fill {
  height: 100%;
  width: 0;
  background: var(--mute);
}
.bar-row.is-true .bar-fill { background: var(--cinnabar); }
.bar-row.is-true .lab { color: var(--cinnabar); font-weight: 700; }
.loss-board {
  border: 1px solid var(--rule);
  padding: 14px 16px 12px;
  background: var(--sheet);
}
.loss-board .eq {
  font-family: var(--mono);
  font-size: 15px;
  color: var(--mute);
  margin: 0 0 6px;
}
.loss-board .num {
  font-family: var(--serif);
  font-size: 42px;
  line-height: 1;
  color: var(--cinnabar);
  letter-spacing: -0.02em;
}
.loss-board .say {
  margin: 10px 0 0;
  font-size: 14.5px;
  color: var(--read);
}
.xent-svg {
  width: 100%;
  height: 148px;
  margin-top: 12px;
  display: block;
}
.essence {
  margin: 16px 0 0;
  padding: 12px 0 0;
  border-top: 1px solid var(--cinnabar-line);
  font-family: var(--serif);
  font-size: 20px;
  color: var(--cinnabar-ink);
}

/* architecture */
.arch {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 20px;
  align-items: start;
}
.stack {
  display: flex;
  flex-direction: column-reverse;
  gap: 6px;
}
.layer {
  appearance: none;
  width: 100%;
  text-align: left;
  font-family: inherit;
  cursor: pointer;
  border: 1px solid var(--rule);
  background: var(--sheet);
  color: var(--ink);
  padding: 10px 12px;
  border-radius: 2px;
}
.layer small {
  display: block;
  color: var(--faint);
  font-size: 11.5px;
  margin-top: 2px;
}
.layer.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar-ink);
}
.layer.is-static {
  cursor: default;
  background: transparent;
  color: var(--mute);
  border-style: dashed;
}
.layer.is-static:hover { background: transparent; }
.layer:hover:not(.is-static) { border-color: var(--cinnabar-line); }
.arch-say {
  min-height: 160px;
  padding: 4px 2px 0 4px;
}
.arch-say h4 {
  font-family: var(--serif);
  font-size: 20px;
  margin: 0 0 8px;
}
.arch-say p { margin: 0 0 10px; }

/* recap */
.recap {
  margin: 12px 0 0;
  padding: 8px 0 0;
}
.recap ol {
  margin: 0;
  padding-left: 1.3em;
  color: var(--read);
}
.recap li { margin: 0 0 8px; }

.next-chap {
  margin: 48px 0 0;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  color: var(--mute);
}
.next-chap strong { color: var(--ink); }

footer.site {
  max-width: 920px;
  margin: 0 auto;
  padding: 8px 28px 48px;
  color: var(--faint);
  font-size: 13px;
}
.page-ch footer.site {
  margin-left: var(--rail-w);
  max-width: 760px;
  padding-left: 36px;
}

.chap-jump {
  display: none;
}

@media (max-width: 920px) {
  .rail { display: none; }
  .page-ch main { margin-left: 0; }
  .page-ch footer.site { margin-left: 0; }
  .cover {
    grid-template-columns: 1fr;
    gap: 28px;
    min-height: 0;
    padding-top: 24px;
  }
  .ntp-flow { grid-template-columns: 1fr; }
  .ntp-mid { min-height: 44px; }
  .xent-grid, .arch { grid-template-columns: 1fr; }
  .article { padding: 0 20px; }
  .page-index main { padding-left: 20px; padding-right: 20px; }
  .toc-list li {
    grid-template-columns: 2em 1fr auto;
  }
  .toc-list .ch-page { display: none; }
  .page-ch main { padding-top: calc(var(--top-h) + 44px); }
  .chap-jump {
    display: flex;
    gap: 8px;
    overflow: auto;
    padding: 8px 20px 4px;
    position: sticky;
    top: var(--top-h);
    background: var(--paper);
    z-index: 20;
  }
  .chap-jump a {
    flex: none;
    text-decoration: none;
    color: var(--mute);
    font-size: 13px;
    padding: 6px 10px;
    border: 1px solid var(--rule-soft);
    background: var(--cell);
  }
  .cell { width: 38px; height: 38px; font-size: 18px; }
}

@media (max-width: 520px) {
  .brand-sub { display: none; }
  .cover h1 { font-size: 30px; }
  .part-head { flex-wrap: wrap; }
  .q-list li { grid-template-columns: 1fr; gap: 2px; }
}

/* ---------- deepen: 讲解块 ---------- */
.why {
  margin: 0 0 16px;
  color: var(--read);
  max-width: 40em;
}
.why strong {
  font-weight: 600;
  color: var(--ink);
}
.bridge {
  margin: 22px 0 0;
  padding: 14px 0 0;
  border-top: 1px dotted rgba(36, 78, 52, 0.28);
  color: var(--mute);
  font-size: 15.5px;
  max-width: 40em;
}
.bridge strong { color: var(--ink); font-weight: 600; }

.cmp {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
  margin: 8px 0 16px;
}
.cmp th {
  text-align: left;
  font-weight: 600;
  font-size: 12.5px;
  color: var(--faint);
  padding: 6px 8px;
  border-bottom: 1px solid var(--rule);
}
.cmp td {
  padding: 8px;
  border-bottom: 1px dotted rgba(36, 78, 52, 0.16);
  vertical-align: top;
  color: var(--read);
}
.cmp td.mono,
.cmp .mono { font-family: var(--mono); font-size: 13.5px; }

.seg {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0 0 14px;
}
.seg button {
  appearance: none;
  cursor: pointer;
  font-family: inherit;
  font-size: 13.5px;
  padding: 7px 12px;
  border: 1px solid var(--rule);
  background: var(--sheet);
  color: var(--mute);
  border-radius: 2px;
}
.seg button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar-ink);
}
.seg button:hover { border-color: var(--cinnabar-line); }

.formula {
  margin: 8px 0 14px;
  padding: 12px 14px;
  background: var(--sheet);
  border: 1px solid var(--rule-soft);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.7;
  color: var(--ink);
}
.formula small {
  display: block;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--faint);
  margin-top: 4px;
}
.formula .hl { color: var(--cinnabar); }

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}
.chip {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 5px 9px;
  border: 1px solid var(--rule);
  background: var(--sheet);
  font-family: var(--serif);
  font-size: 16px;
  line-height: 1.3;
}
.chip .id {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--faint);
}
.chip.is-next {
  border-color: var(--cinnabar);
  color: var(--cinnabar-ink);
  background: #f8ece8;
}
.chip.is-mask {
  opacity: 0.38;
  border-style: dashed;
}

.four-q {
  display: grid;
  gap: 0;
  margin: 8px 0 18px;
}
.four-q details {
  border-bottom: 1px dotted rgba(36, 78, 52, 0.18);
  padding: 10px 0;
}
.four-q summary {
  cursor: pointer;
  display: grid;
  grid-template-columns: 1.2em 5.5em 1fr;
  gap: 8px 12px;
  list-style: none;
  font-size: 15.5px;
  color: var(--read);
  align-items: start;
}
.four-q summary::-webkit-details-marker { display: none; }
.four-q summary::marker { content: ""; }
.four-q summary::before {
  content: "▸ ";
  color: var(--faint);
  font-family: var(--mono);
  font-size: 12px;
}
.four-q details[open] summary::before { content: "▾ "; }
.four-q summary .k {
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--cinnabar);
  padding-top: 3px;
}
.four-q .more {
  margin: 8px 0 4px 0;
  padding-left: 0;
  color: var(--mute);
  font-size: 15px;
  max-width: 40em;
}

.hill-svg {
  width: 100%;
  height: 160px;
  display: block;
}
.hill-meta {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 13.5px;
  color: var(--mute);
  margin-top: 8px;
}

.onehot {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin: 0 0 14px;
}
.onehot .col {
  border: 1px solid var(--rule-soft);
  padding: 10px 12px;
  background: var(--sheet);
}
.onehot .k {
  font-size: 12px;
  color: var(--faint);
  display: block;
  margin-bottom: 8px;
}
.onehot .vec {
  display: flex;
  gap: 6px;
}
.onehot .vec span {
  flex: 1;
  text-align: center;
  font-family: var(--mono);
  font-size: 13px;
  padding: 8px 0;
  border: 1px solid var(--rule);
  background: var(--cell);
}
.onehot .vec span.is-1 {
  border-color: var(--cinnabar);
  color: var(--cinnabar);
  background: #f8ece8;
}

.block-group {
  position: relative;
  border: 1px solid var(--cinnabar-line);
  padding: 8px 6px 8px 8px;
  display: flex;
  flex-direction: column-reverse;
  gap: 6px;
  margin: 2px 0;
}
.block-tag {
  position: absolute;
  left: -2.6em;
  top: 50%;
  transform: translateY(-50%) rotate(-90deg);
  transform-origin: center;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--cinnabar);
  white-space: nowrap;
}
.stack { position: relative; }
.layer.is-on small { color: var(--cinnabar-ink); }

/* ---------- ch2 widgets ---------- */
.tok-input {
  width: 100%;
  font-family: inherit;
  font-size: 16px;
  padding: 10px 12px;
  border: 1px solid var(--rule);
  background: var(--cell);
  color: var(--ink);
  border-radius: 2px;
}
.tok-input:focus {
  outline: 2px solid var(--cinnabar);
  outline-offset: 2px;
  border-color: var(--cinnabar);
}
.tok-meta {
  margin: 10px 0 0;
  font-size: 13.5px;
  color: var(--mute);
}
.merge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
  min-height: 36px;
  margin: 6px 0;
}
.merge-row .chip { font-size: 15px; }
.merge-k {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--faint);
  width: 4.2em;
  flex: none;
}

.windows {
  display: grid;
  gap: 8px;
  margin: 12px 0;
}
.win-bar {
  display: grid;
  grid-template-columns: 4.5em 1fr;
  gap: 8px;
  align-items: center;
}
.win-bar .k {
  font-size: 12px;
  color: var(--faint);
}
.win-track {
  display: flex;
  gap: 2px;
  flex-wrap: wrap;
}
.win-track span {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  font-family: var(--serif);
  font-size: 14px;
  border: 1px solid var(--rule-soft);
  background: var(--sheet);
}
.win-track span.in {
  background: #e7f0e6;
  border-color: var(--rule);
}
.win-track span.tgt {
  color: var(--cinnabar);
  border-color: var(--cinnabar-line);
  background: #f8ece8;
}
.batch {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 12px;
}
.batch .col {
  border: 1px solid var(--rule);
  padding: 10px;
  background: var(--sheet);
  font-family: var(--serif);
  font-size: 16px;
}
.batch .k {
  display: block;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--faint);
  margin-bottom: 6px;
}

.qkv {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin: 0 0 14px;
}
.qkv button {
  appearance: none;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 10px 12px;
  color: var(--ink);
}
.qkv button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
}
.qkv b {
  display: block;
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}
.qkv small {
  display: block;
  color: var(--mute);
  font-size: 12.5px;
  line-height: 1.45;
}
.sent-tok {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0 0 12px;
}
.sent-tok button {
  appearance: none;
  cursor: pointer;
  font-family: var(--serif);
  font-size: 20px;
  width: 48px;
  height: 48px;
  border: 1px solid var(--rule);
  background: var(--sheet);
  color: var(--ink);
}
.sent-tok button.is-q {
  border-color: var(--cinnabar);
  color: var(--cinnabar);
  background: #f8ece8;
}
.sent-tok button.is-see {
  background: #e7f0e6;
}
.sent-tok button.is-hid {
  opacity: 0.32;
  border-style: dashed;
}

.mask {
  display: grid;
  gap: 3px;
  margin: 8px 0 4px;
  overflow: auto;
}
.mask-row {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 36px;
  gap: 3px;
}
.mask-row span {
  display: grid;
  place-items: center;
  height: 36px;
  font-size: 11px;
  font-family: var(--mono);
  border: 1px solid var(--rule-soft);
  background: var(--sheet);
}
.mask-row span.lab {
  background: transparent;
  border-color: transparent;
  color: var(--faint);
  font-size: 12px;
  font-family: var(--serif);
}
.mask-row span.see {
  background: #e7f0e6;
}
.mask-row span.hide {
  background: repeating-linear-gradient(
    -45deg,
    var(--cell),
    var(--cell) 4px,
    #eadfdf 4px,
    #eadfdf 8px
  );
  color: var(--faint);
}
.mask-row span.focus {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar);
}

.ffn-pipe {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr auto 1fr;
  gap: 6px;
  align-items: center;
  margin: 8px 0 12px;
}
.ffn-pipe .box {
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 10px 8px;
  text-align: center;
  font-size: 13px;
}
.ffn-pipe .box b {
  display: block;
  font-family: var(--mono);
  font-size: 14px;
  margin-bottom: 2px;
}
.ffn-pipe .arr { color: var(--faint); font-size: 16px; }

.loop {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  margin: 0 0 14px;
}
.loop button {
  appearance: none;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 10px 10px 12px;
  color: var(--ink);
  min-height: 92px;
}
.loop button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
}
.loop .n {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--cinnabar);
  display: block;
  margin-bottom: 4px;
}
.loop b {
  display: block;
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}
.loop small {
  color: var(--mute);
  font-size: 12.5px;
  line-height: 1.4;
}
.code-run {
  list-style: none;
  margin: 0 0 12px;
  padding: 10px 12px;
  background: var(--sheet);
  border: 1px solid var(--rule-soft);
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.7;
}
.code-run li { color: var(--faint); }
.code-run li.is-on { color: var(--cinnabar-ink); }

.sizes {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}
.sizes button {
  appearance: none;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 12px;
  color: var(--ink);
}
.sizes button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
}
.sizes b {
  display: block;
  font-family: var(--serif);
  font-size: 16px;
}
.sizes small {
  display: block;
  color: var(--mute);
  font-size: 12px;
  margin-top: 4px;
}

.two-sent {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 8px 0 12px;
}
.two-sent .col {
  border: 1px solid var(--rule);
  padding: 10px;
  background: var(--sheet);
}
.two-sent .col.is-on { border-color: var(--cinnabar); }
.knob-row {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}
.knob {
  flex: 1;
  height: 10px;
  background: var(--sheet-2);
  border: 1px solid var(--rule-soft);
  position: relative;
}
.knob i {
  position: absolute;
  top: -4px;
  width: 10px;
  height: 18px;
  background: var(--cinnabar);
}

@media (max-width: 920px) {
  .onehot, .qkv, .loop, .batch, .two-sent { grid-template-columns: 1fr; }
  .sizes { grid-template-columns: 1fr 1fr; }
  .ffn-pipe {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .ffn-pipe .arr { transform: rotate(90deg); }
  .block-tag { display: none; }
}

@media (max-width: 520px) {
  .loop { grid-template-columns: 1fr 1fr; }
}

/* ---------- 全书扩展控件 ---------- */
.toc-list a.live .ch-state.is-mid { color: var(--mute); }
.toc-list a.live .ch-state.is-done { color: var(--ok); }

.cycle {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 10px;
  align-items: center;
  margin: 8px 0 12px;
}
.cycle-col {
  display: grid;
  gap: 8px;
}
.cycle button,
.node {
  appearance: none;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 10px 12px;
  color: var(--ink);
}
.cycle button.is-on,
.node.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar-ink);
}
.cycle button b,
.node b {
  display: block;
  font-family: var(--serif);
  font-size: 16px;
}
.cycle button small,
.node small {
  display: block;
  color: var(--mute);
  font-size: 12.5px;
  margin-top: 2px;
}
.cycle-mid {
  font-family: var(--serif);
  color: var(--cinnabar);
  font-size: 22px;
  text-align: center;
  min-width: 1.4em;
}

.pole-stage {
  position: relative;
  height: 180px;
  border: 1px solid var(--rule);
  background: var(--sheet);
  overflow: hidden;
  margin: 8px 0 12px;
}
.pole-ground {
  position: absolute;
  left: 0; right: 0; bottom: 28px;
  height: 1px;
  background: var(--rule);
}
.cart {
  position: absolute;
  bottom: 22px;
  width: 56px;
  height: 16px;
  margin-left: -28px;
  background: var(--ink);
  border-radius: 2px;
  transition: left 0.18s var(--ease);
}
.pole {
  position: absolute;
  left: 50%;
  bottom: 16px;
  width: 4px;
  height: 92px;
  margin-left: -2px;
  background: var(--cinnabar);
  transform-origin: 50% 100%;
  transition: transform 0.18s var(--ease);
}
.pole-fail {
  position: absolute;
  inset: auto 12px 6px 12px;
  font-size: 13px;
  color: var(--mute);
}

.traj {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin: 8px 0;
}
.traj span {
  min-width: 36px;
  padding: 6px 8px;
  border: 1px solid var(--rule-soft);
  background: var(--sheet);
  font-family: var(--mono);
  font-size: 12px;
  text-align: center;
}
.traj span.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar-ink);
}
.traj span.fail {
  border-color: var(--cinnabar-line);
  color: var(--cinnabar);
}

.plot {
  width: 100%;
  height: 180px;
  display: block;
  background: var(--sheet);
  border: 1px solid var(--rule-soft);
}

.matrix {
  display: grid;
  gap: 4px;
  margin: 8px 0 12px;
  overflow: auto;
}
.matrix-row {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(64px, 1fr);
  gap: 4px;
}
.matrix-row span,
.matrix-row button {
  appearance: none;
  font-family: var(--mono);
  font-size: 12px;
  min-height: 40px;
  border: 1px solid var(--rule-soft);
  background: var(--sheet);
  color: var(--ink);
  display: grid;
  place-items: center;
  cursor: pointer;
  padding: 4px;
}
.matrix-row span.lab,
.matrix-row button.lab {
  background: transparent;
  border-color: transparent;
  color: var(--faint);
  font-family: var(--sans);
  cursor: default;
}
.matrix-row button.is-diag {
  border-color: var(--ok);
  background: var(--ok-soft);
}
.matrix-row button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
}

.patch-grid {
  display: grid;
  gap: 3px;
  margin: 8px 0;
  width: min(100%, 280px);
}
.patch-grid span {
  aspect-ratio: 1;
  border: 1px solid var(--rule);
  background: var(--sheet);
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--mute);
  cursor: pointer;
}
.patch-grid span.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar);
}
.patch-grid span.cls {
  border-style: dashed;
  color: var(--cinnabar);
}

.pix {
  display: grid;
  gap: 2px;
  width: min(100%, 220px);
  margin: 8px 0;
}
.pix i {
  display: block;
  aspect-ratio: 1;
  background: #1a2a1c;
}

.pref {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 8px 0 12px;
}
.pref .col {
  border: 1px solid var(--rule);
  padding: 12px;
  background: var(--sheet);
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  color: var(--ink);
}
.pref .col.win {
  border-color: var(--ok);
  background: var(--ok-soft);
}
.pref .col.lose {
  border-color: var(--cinnabar-line);
  background: #f8ece8;
}
.pref .k {
  display: block;
  font-size: 12px;
  color: var(--faint);
  margin-bottom: 6px;
}

.flow {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: stretch;
  margin: 8px 0 12px;
}
.flow button {
  appearance: none;
  cursor: pointer;
  flex: 1;
  min-width: 108px;
  text-align: left;
  font-family: inherit;
  border: 1px solid var(--rule);
  background: var(--sheet);
  padding: 10px 12px;
  color: var(--ink);
}
.flow button.is-on {
  border-color: var(--cinnabar);
  background: #f8ece8;
}
.flow button b {
  display: block;
  font-family: var(--serif);
  font-size: 15px;
}
.flow button small {
  display: block;
  color: var(--mute);
  font-size: 12px;
  margin-top: 2px;
}
.flow .arr {
  align-self: center;
  color: var(--faint);
}

.group-list {
  display: grid;
  gap: 6px;
  margin: 8px 0;
}
.group-row {
  display: grid;
  grid-template-columns: 4.5em 1fr 4em;
  gap: 8px;
  align-items: center;
  font-size: 13.5px;
}
.group-row .track {
  height: 10px;
  background: var(--sheet-2);
  border: 1px solid var(--rule-soft);
}
.group-row .fill {
  height: 100%;
  background: var(--mute);
}
.group-row.is-best .fill { background: var(--ok); }
.group-row.is-worst .fill { background: var(--cinnabar); }

.book-map {
  display: grid;
  gap: 10px;
}
.book-map a {
  display: grid;
  grid-template-columns: 2em 1fr auto;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
  padding: 10px 12px;
  border: 1px solid var(--rule);
  background: var(--sheet);
}
.book-map a:hover { border-color: var(--cinnabar); }
.book-map .pn {
  font-family: var(--serif);
  color: var(--cinnabar);
}
.book-map small { color: var(--faint); font-size: 12.5px; }

.legend-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cinnabar);
  margin-right: 4px;
}

@media (max-width: 920px) {
  .cycle, .pref { grid-template-columns: 1fr; }
  .cycle-mid { transform: rotate(90deg); }
}

/* ---------- 章末自测 ---------- */
.toc-list li {
  grid-template-columns: 2.4em 1fr auto auto auto;
}
.toc-list .ch-quiz {
  font-size: 12px;
  min-width: 5.6em;
  text-align: right;
  color: var(--faint);
  font-variant-numeric: tabular-nums;
}
.toc-list a.live .ch-quiz.is-mid { color: var(--cinnabar); }
.toc-list a.live .ch-quiz.is-done { color: var(--ok); }

.quiz-bar {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
  margin: 0 0 18px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--rule-soft);
  font-size: 14px;
  color: var(--mute);
}
.quiz-bar .n {
  font-family: var(--serif);
  color: var(--cinnabar);
  font-size: 22px;
  margin-right: 4px;
}
.quiz-item {
  margin: 0 0 8px;
  padding: 16px 0 18px;
  border-bottom: 1px dotted rgba(36, 78, 52, 0.18);
}
.quiz-q {
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.55;
  margin: 0 0 12px;
  color: var(--ink);
}
.quiz-q b {
  font-family: var(--mono);
  font-weight: 500;
  color: var(--cinnabar);
  margin-right: 6px;
}
.quiz-choices {
  display: grid;
  gap: 8px;
}
.quiz-choices button {
  appearance: none;
  text-align: left;
  font-family: inherit;
  font-size: 15.5px;
  line-height: 1.5;
  padding: 10px 12px;
  border: 1px solid var(--rule);
  background: var(--sheet);
  color: var(--ink);
  cursor: pointer;
  border-radius: 2px;
}
.quiz-choices button:hover:not(:disabled) {
  border-color: var(--cinnabar-line);
  background: var(--cell);
}
.quiz-choices button:disabled { cursor: default; }
.quiz-choices button.is-right {
  border-color: var(--ok);
  background: var(--ok-soft);
  color: var(--ok);
}
.quiz-choices button.is-wrong {
  border-color: var(--cinnabar);
  background: #f8ece8;
  color: var(--cinnabar-ink);
}
.quiz-why {
  margin: 10px 0 0;
  font-size: 14.5px;
  color: var(--mute);
  max-width: 42em;
}
.quiz-why.is-ok { color: var(--ok); }
.quiz-why.is-no { color: var(--cinnabar-ink); }

@media (max-width: 920px) {
  .toc-list li {
    grid-template-columns: 2em 1fr auto auto;
  }
  .toc-list .ch-page { display: none; }
}