/* =========================================================================
   Attention 注疏本 — a printed, annotated edition
   ground · ink · rubric · gold · verdigris
   ========================================================================= */

@font-face {
  font-family: "EB Garamond";
  src: url("../fonts/eb-garamond-latin-400-normal.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "EB Garamond";
  src: url("../fonts/eb-garamond-latin-500-normal.woff2") format("woff2");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "EB Garamond";
  src: url("../fonts/eb-garamond-latin-600-normal.woff2") format("woff2");
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "EB Garamond";
  src: url("../fonts/eb-garamond-latin-400-italic.woff2") format("woff2");
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}
@font-face {
  font-family: "Cormorant Garamond";
  src: url("../fonts/cormorant-garamond-latin-500-normal.woff2") format("woff2");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Cormorant Garamond";
  src: url("../fonts/cormorant-garamond-latin-600-normal.woff2") format("woff2");
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Noto Serif SC";
  src: url("../fonts/noto-serif-sc-400.woff2") format("woff2");
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: "Noto Serif SC";
  src: url("../fonts/noto-serif-sc-600.woff2") format("woff2");
  font-weight: 600;
  font-display: swap;
}
@font-face {
  font-family: "Noto Serif SC";
  src: url("../fonts/noto-serif-sc-700.woff2") format("woff2");
  font-weight: 700;
  font-display: swap;
}

:root {
  --ground: #e9e3d4;
  --ground-2: #ded6c2;
  --ground-3: #d0c7ae;
  --paper-white: #f6f1e1;
  --ink: #1e1b16;
  --ink-soft: #4b4435;
  --ink-faint: #6b6350;
  --rubric: #8b2f24;
  --rubric-deep: #6f241b;
  --rubric-wash: #e6d3c8;
  --gold: #a98c52;
  --verdigris: #3e5b50;
  --night: #14201b;
  --night-2: #1c2a24;
  --night-ink: #e9e3d4;
  --night-soft: #b9b29f;

  --serif-latin: "EB Garamond", "Noto Serif SC", "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  --serif-display: "Cormorant Garamond", "EB Garamond", "Noto Serif SC", "Iowan Old Style", Georgia, serif;
  --serif-cn: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --math: "Cambria Math", "STIX Two Math", "Latin Modern Math", var(--serif-latin);

  --fs-display: clamp(3.1rem, 6vw, 5.4rem);
  --fs-title: clamp(2rem, 3.6vw, 2.9rem);
  --fs-head: clamp(1.28rem, 1.7vw, 1.55rem);
  --fs-body: clamp(1.02rem, 1.06vw, 1.09rem);
  --fs-small: 0.84rem;

  --gutter: clamp(20px, 4.2vw, 64px);
  --axis: 42%;
  --measure: 40rem;
  --topbar-h: 68px;

  --ease: cubic-bezier(0.22, 0.61, 0.24, 1);
  --dur: 620ms;
}

/* ---------- reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font-family: var(--serif-cn);
  font-size: var(--fs-body);
  line-height: 1.9;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  font-kerning: normal;
}
img, svg { max-width: 100%; height: auto; }
h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
em { font-style: italic; }
strong { font-weight: 600; }
::selection { background: var(--rubric); color: var(--paper-white); }
:focus-visible { outline: 2px solid var(--rubric); outline-offset: 3px; }
[hidden] { display: none !important; }

.skip-link {
  position: fixed;
  top: -100px;
  left: var(--gutter);
  z-index: 200;
  background: var(--ink);
  color: var(--ground);
  padding: 10px 18px;
}
.skip-link:focus { top: 12px; }

/* ---------- type utilities ---------- */
.latin { font-family: var(--serif-latin); }
.display { font-family: var(--serif-display); font-weight: 600; letter-spacing: -0.01em; }
.small { font-size: var(--fs-small); }
.soft { color: var(--ink-soft); }
.rubric-text { color: var(--rubric); }
.m { font-family: var(--serif-latin); font-style: italic; letter-spacing: 0.01em; white-space: nowrap; }
code, kbd {
  font-family: "IBM Plex Mono", "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 0.9em;
  background: var(--ground-2);
  padding: 0.1em 0.35em;
}
a:not(.btn):not(.nav__link):not(.wordmark):not(.chapter):not(.footer__top) {
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  text-decoration-color: color-mix(in srgb, var(--rubric) 45%, transparent);
}
a:not(.btn):not(.nav__link):not(.wordmark):not(.chapter):hover {
  color: var(--rubric);
  text-decoration-color: var(--rubric);
}

/* ---------- topbar ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--ground);
  transition: background 220ms var(--ease);
}
.topbar.is-scrolled { background: var(--ground-2); }
.topbar__inner {
  display: flex;
  align-items: center;
  gap: clamp(18px, 3vw, 48px);
  height: var(--topbar-h);
  padding-inline: var(--gutter);
  max-width: 1500px;
  margin-inline: auto;
}
.wordmark {
  display: flex;
  align-items: baseline;
  gap: 10px;
  flex: 0 0 auto;
  white-space: nowrap;
}
.wordmark__latin {
  font-family: var(--serif-display);
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: 0.005em;
}
.wordmark__cn {
  font-size: 0.82rem;
  letter-spacing: 0.26em;
  color: var(--ink-soft);
  padding-left: 2px;
}
.nav {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.1vw, 32px);
  margin-left: auto;
}
.nav__link {
  font-size: 1rem;
  letter-spacing: 0.02em;
  color: var(--ink-soft);
  padding: 6px 0;
  position: relative;
  white-space: nowrap;
  transition: color 180ms var(--ease);
}
.nav__link i {
  font-style: normal;
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  color: var(--ink-faint);
  margin-right: 6px;
  transition: color 180ms var(--ease);
}
.nav__link:hover { color: var(--ink); }
.nav__link[aria-current="page"] { color: var(--rubric); }
.nav__link[aria-current="page"] i { color: var(--rubric); }
.nav-toggle {
  display: none;
  margin-left: auto;
  font-size: 0.85rem;
  letter-spacing: 0.18em;
  padding: 10px 4px;
  color: var(--ink-soft);
}
.read-rail {
  height: 2px;
  background: color-mix(in srgb, var(--ink) 10%, transparent);
}
#read-bar {
  display: block;
  height: 100%;
  width: 0;
  background: var(--rubric);
}

/* ---------- generic layout ---------- */
#main { min-height: 60svh; }
.wrap {
  width: 100%;
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.spread {
  display: grid;
  grid-template-columns: var(--axis) calc(100% - var(--axis));
  align-items: stretch;
}
.spread__margin { padding-right: clamp(22px, 3.4vw, 60px); }
.spread__body { max-width: var(--measure); }
.running-head {
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-faint);
  line-height: 1.5;
}
.running-head .cn {
  display: block;
  font-family: var(--serif-cn);
  letter-spacing: 0.32em;
  margin-top: 4px;
}
.part-no {
  font-family: var(--serif-display);
  font-size: clamp(2.4rem, 4vw, 3.6rem);
  line-height: 1;
  color: var(--rubric);
  font-weight: 500;
  margin-top: 18px;
}
.rule-space { height: clamp(48px, 7vw, 96px); }

/* ---------- cover ---------- */
.cover {
  min-height: calc(100svh - var(--topbar-h));
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding-bottom: clamp(44px, 7vh, 88px);
  position: relative;
}
.cover__colophon {
  position: absolute;
  top: clamp(20px, 4vh, 48px);
  left: var(--gutter);
  right: var(--gutter);
  display: flex;
  justify-content: space-between;
  gap: 24px;
  font-family: var(--serif-latin);
  font-size: 0.85rem;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
}
.cover__grid {
  display: grid;
  grid-template-columns: var(--axis) calc(100% - var(--axis));
  align-items: end;
}
.cover__left {
  padding-right: clamp(24px, 4vw, 72px);
  padding-bottom: 0.5rem;
}
.cover__standfirst {
  font-size: clamp(1rem, 1.15vw, 1.13rem);
  line-height: 2;
  color: var(--ink-soft);
  max-width: 27em;
  margin-bottom: 2rem;
}
.cover__standfirst strong { color: var(--ink); font-weight: 600; }
.cover__actions { display: flex; align-items: center; gap: 22px; flex-wrap: wrap; }
.cover__more {
  font-size: 0.88rem;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
}
.cover__title {
  font-family: var(--serif-display);
  font-weight: 600;
  font-size: var(--fs-display);
  line-height: 0.9;
  letter-spacing: -0.025em;
  color: var(--ink);
}
.cover__title h1 { margin: 0; font: inherit; letter-spacing: inherit; }
.cover__title span { display: block; }
.cover__title .mask-line > span { white-space: nowrap; }
.cover__title span + span { margin-top: 0.02em; }
.cover__cn {
  margin-top: clamp(18px, 2.2vw, 28px);
  font-size: clamp(1.15rem, 1.7vw, 1.45rem);
  letter-spacing: 0.24em;
  color: var(--ink-soft);
  font-weight: 400;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.cover__authors {
  margin-top: 1.6rem;
  font-family: var(--serif-latin);
  font-size: 1rem;
  letter-spacing: 0.01em;
  color: var(--ink-faint);
  line-height: 1.8;
  max-width: 35em;
}
.cover__authors em { font-style: normal; letter-spacing: 0.14em; }
.seal {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: var(--rubric);
  color: var(--paper-white);
  font-family: var(--serif-cn);
  font-size: 1.4rem;
  line-height: 1;
  margin-left: 0;
  position: relative;
  flex: 0 0 auto;
}
.seal::after {
  content: "";
  position: absolute;
  inset: 3px;
  /* taste-skill-ignore: 朱印的内框就是印章的刻线本身，不是页面分隔线 */
  border: 1px solid color-mix(in srgb, var(--paper-white) 55%, transparent);
}
.cover__hint {
  margin-top: 1.2rem;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  color: var(--ink-faint);
}

/* tipped-in facsimile plate */
.cover__plate {
  position: absolute;
  top: clamp(96px, 13vh, 156px);
  left: calc(var(--gutter) + clamp(0px, 1.4vw, 18px));
  width: clamp(220px, 23vw, 336px);
  margin: 0;
}
.cover__plate-frame {
  overflow: hidden;
  background: #fff;
  padding: 10px;
}
.cover__plate img {
  display: block;
  width: 100%;
  filter: grayscale(0.08) contrast(1.02);
  animation: plate-drift 24s ease-in-out infinite alternate;
}
.cover__plate figcaption {
  margin-top: 9px;
  font-family: var(--serif-cn);
  font-size: 0.82rem;
  color: var(--ink-faint);
  letter-spacing: 0.06em;
}
@keyframes plate-drift {
  from { transform: scale(1); }
  to { transform: scale(1.035) translateY(-3px); }
}

/* ---------- plates band ---------- */
.plates {
  margin-top: clamp(70px, 9vw, 120px);
  padding-bottom: clamp(10px, 2vw, 24px);
}
.plates__head {
  margin-bottom: clamp(28px, 4vw, 48px);
  max-width: 52rem;
}
.plates__head h2 {
  font-family: var(--serif-cn);
  font-size: var(--fs-title);
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.35;
}
.plates__head p {
  margin-top: 1rem;
  max-width: 42em;
  color: var(--ink);
  line-height: 1.95;
}
.plates__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(12px, 2vw, 24px);
}
.plates__grid figure { margin: 0; }
.plates__frame {
  background: var(--paper-white);
  padding: clamp(8px, 1vw, 14px);
  height: clamp(220px, 22vw, 320px);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.plates__frame img {
  display: block;
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
  cursor: zoom-in;
}
.plates__grid figcaption {
  margin-top: 10px;
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--ink-soft);
}
.plates__grid figcaption b {
  display: block;
  font-family: var(--serif-latin);
  color: var(--rubric);
  font-weight: 500;
  letter-spacing: 0.06em;
  margin-bottom: 2px;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 12px 24px;
  background: var(--rubric);
  color: var(--paper-white);
  font-family: var(--serif-cn);
  font-size: 0.95rem;
  letter-spacing: 0.14em;
  text-decoration: none;
  border: 0;
  transition: background 180ms var(--ease), transform 180ms var(--ease);
}
.btn:hover { background: var(--rubric-deep); color: var(--paper-white); }
.btn:active { transform: translateY(1px); }
.btn--ink { background: var(--ink); }
.btn--ink:hover { background: #000; }
.btn--ghost {
  background: transparent;
  color: var(--ink);
  /* taste-skill-ignore: 次要按钮是真实的表单控件，需要可见边界 */
  border: 1px solid color-mix(in srgb, var(--ink) 35%, transparent);
}
.btn--ghost:hover { background: var(--ground-2); color: var(--ink); }
.btn[disabled] { opacity: 0.45; cursor: not-allowed; }
.btn--small { min-height: 38px; padding: 8px 14px; font-size: 0.82rem; letter-spacing: 0.08em; }
.text-link {
  font-size: 0.9rem;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
  text-decoration-color: color-mix(in srgb, var(--ink) 30%, transparent);
  transition: color 180ms var(--ease), text-decoration-color 180ms var(--ease);
}
.text-link:hover { color: var(--rubric); text-decoration-color: var(--rubric); }

/* ---------- volume index ---------- */
.volume { padding-top: clamp(56px, 8vw, 112px); padding-bottom: clamp(80px, 10vw, 140px); }
.volume__head { padding-bottom: clamp(40px, 5vw, 64px); }
.volume h1 {
  font-family: var(--serif-cn);
  font-size: var(--fs-title);
  font-weight: 600;
  letter-spacing: 0.06em;
  line-height: 1.25;
}
.volume__en {
  font-family: var(--serif-latin);
  font-style: italic;
  font-size: 1.15rem;
  color: var(--ink-faint);
  margin-top: 0.6rem;
}
.volume__lead {
  margin-top: 1.4rem;
  color: var(--ink-soft);
  line-height: 2;
  max-width: 34em;
}
.chapter-list { list-style: none; }
.chapter {
  display: grid;
  grid-template-columns: var(--axis) calc(100% - var(--axis));
  padding: clamp(22px, 2.6vw, 32px) 0;
  text-decoration: none;
  color: var(--ink);
  transition: background 180ms var(--ease);
  margin-inline: calc(var(--gutter) * -0.35);
  padding-inline: calc(var(--gutter) * 0.35);
}
.chapter:hover { background: color-mix(in srgb, var(--ground-2) 70%, transparent); }
.chapter__no {
  font-family: var(--serif-display);
  font-size: clamp(1.5rem, 2.2vw, 2rem);
  line-height: 1.25;
  color: var(--rubric);
  font-weight: 500;
  letter-spacing: 0.02em;
}
.chapter__main { display: flex; flex-direction: column; gap: 6px; }
.chapter__title {
  font-size: clamp(1.12rem, 1.5vw, 1.32rem);
  font-weight: 600;
  letter-spacing: 0.03em;
  line-height: 1.55;
}
.chapter__title span { color: var(--ink-faint); font-family: var(--serif-latin); font-weight: 400; font-style: italic; margin-left: 10px; font-size: 0.85em; }
.chapter__lead { color: var(--ink-soft); font-size: 0.95rem; line-height: 1.8; max-width: 38em; }
.chapter__meta {
  display: flex;
  gap: 18px;
  align-items: center;
  margin-top: 4px;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.chapter__done { color: var(--verdigris); }
.volume__note {
  margin-top: clamp(48px, 6vw, 80px);
  padding: 26px 30px;
  background: var(--ground-2);
  color: var(--ink-soft);
  font-size: 0.88rem;
  line-height: 1.9;
  max-width: 58em;
}

/* ---------- part page ---------- */
.part { padding-bottom: clamp(70px, 9vw, 130px); }
.part-head { padding-top: clamp(48px, 7vw, 92px); padding-bottom: clamp(36px, 5vw, 64px); }
.part-head h1 {
  font-family: var(--serif-cn);
  font-size: clamp(1.9rem, 3.2vw, 2.6rem);
  font-weight: 600;
  letter-spacing: 0.05em;
  line-height: 1.35;
}
.part-en {
  font-family: var(--serif-latin);
  font-style: italic;
  font-size: clamp(1.15rem, 1.7vw, 1.45rem);
  color: var(--ink-faint);
  margin-top: 0.55rem;
  line-height: 1.4;
}
.part-lead {
  margin-top: 1.3rem;
  color: var(--ink-soft);
  line-height: 2;
  max-width: 36em;
}
.part-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin-top: 1.4rem;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
}
.part-meta span::before { content: "·"; margin-right: 22px; color: var(--gold); }
.part-meta span:first-child::before { content: none; }

.part-intro { padding-bottom: clamp(36px, 5vw, 64px); }
.margin-block { margin-bottom: clamp(28px, 3vw, 42px); }
.margin-block__title {
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 14px;
}
.points { list-style: none; counter-reset: pt; }
.points li {
  counter-increment: pt;
  position: relative;
  padding-left: 1.7em;
  margin-bottom: 12px;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--ink-soft);
}
.points li::before {
  content: counter(pt, upper-roman);
  position: absolute;
  left: 0;
  top: 0.15em;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  color: var(--rubric);
  letter-spacing: 0.05em;
}
.terms { font-size: 0.9rem; }
.terms dt {
  font-weight: 600;
  margin-top: 14px;
  line-height: 1.6;
}
.terms dt em { font-family: var(--serif-latin); font-weight: 400; color: var(--ink-faint); font-size: 0.9em; }
.terms dd { color: var(--ink-soft); line-height: 1.8; font-size: 0.88rem; }
.margin-actions { display: flex; flex-direction: column; gap: 10px; }

.lesson-aside {
  position: sticky;
  top: calc(var(--topbar-h) + 34px);
  max-width: 17rem;
}
.lesson-aside__no {
  margin-top: 18px;
  font-family: var(--serif-cn);
  font-size: 0.85rem;
  letter-spacing: 0.16em;
  color: var(--rubric);
}
.lesson-aside__title {
  margin-top: 8px;
  font-size: 1.06rem;
  font-weight: 600;
  line-height: 1.6;
}
.lesson-aside__meta {
  margin-top: 8px;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  color: var(--ink-faint);
}
.lesson-aside__note {
  margin-top: 18px;
  font-size: 0.85rem;
  line-height: 1.85;
  color: var(--ink-soft);
}
.lesson-aside__back { margin-top: 18px; }

/* ---------- prose ---------- */
.prose { color: var(--ink); }
.prose p { margin-bottom: 1.15em; }
.prose h4 {
  font-family: var(--serif-cn);
  font-size: var(--fs-head);
  font-weight: 600;
  letter-spacing: 0.04em;
  margin: 2.2em 0 0.8em;
  line-height: 1.5;
}
.prose ul, .prose ol { margin: 0 0 1.3em 1.4em; }
.prose li { margin-bottom: 0.4em; }
.prose blockquote {
  margin: 1.8em 0;
  padding-left: 1.6em;
  border-left: 2px solid var(--rubric);
  color: var(--ink-soft);
  font-style: italic;
}
.prose blockquote cite {
  display: block;
  margin-top: 0.6em;
  font-style: normal;
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
}
.term {
  text-decoration: underline dotted;
  text-decoration-color: color-mix(in srgb, var(--rubric) 60%, transparent);
  text-underline-offset: 4px;
  cursor: help;
}
.callout {
  margin: 2em 0;
  padding: 22px 26px;
  background: var(--ground-2);
}
.callout--key { background: color-mix(in srgb, var(--verdigris) 12%, var(--ground)); }
.callout--warn { background: color-mix(in srgb, var(--rubric) 9%, var(--ground)); }
.callout__title {
  font-family: var(--serif-cn);
  font-size: 0.82rem;
  letter-spacing: 0.2em;
  color: var(--rubric);
  margin-bottom: 8px;
}
.callout--key .callout__title { color: var(--verdigris); }
.callout p:last-child { margin-bottom: 0; }

.math-block {
  margin: 1.8em 0;
  padding: 6px 0;
  overflow-x: auto;
  text-align: center;
}
.math-block .katex-display { margin: 0.6em 0; }
.math-label {
  display: block;
  margin-top: 4px;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  color: var(--ink-faint);
  letter-spacing: 0.08em;
}
.math-note {
  margin: 0.6em auto 0;
  max-width: 34em;
  font-size: 0.86rem;
  color: var(--ink-soft);
  text-align: left;
}

.table-wrap { margin: 2em 0; overflow-x: auto; }
.table-wrap table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  line-height: 1.6;
}
.table-wrap caption {
  text-align: left;
  font-size: 0.82rem;
  color: var(--ink-faint);
  margin-bottom: 10px;
}
.table-wrap th, .table-wrap td {
  padding: 10px 14px 10px 0;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid color-mix(in srgb, var(--ink) 16%, transparent);
}
.table-wrap th {
  font-weight: 600;
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
  text-transform: uppercase;
  border-bottom-color: color-mix(in srgb, var(--ink) 45%, transparent);
}

figure.fig {
  margin: 2.4em 0;
}
figure.fig .fig__frame {
  background: var(--paper-white);
  padding: clamp(12px, 1.6vw, 22px);
}
figure.fig img { display: block; width: 100%; }
figure.fig figcaption {
  margin-top: 10px;
  font-size: 0.81rem;
  line-height: 1.7;
  color: var(--ink-faint);
}
figure.fig figcaption b { color: var(--ink-soft); font-weight: 600; }
figure.fig--narrow { max-width: 32rem; }
.figure-credit { display: block; margin-top: 4px; font-size: 0.82rem; color: var(--ink-faint); }

.widget-slot { margin: 2.4em 0; }
.widget-caption {
  margin-top: 12px;
  font-size: 0.82rem;
  color: var(--ink-faint);
  line-height: 1.7;
}

.defs { margin: 2em 0; }
.defs__item { padding: 16px 20px; }
.defs__item:nth-child(odd) { background: var(--ground-2); }
.defs__term { font-weight: 600; }
.defs__term em { font-family: var(--serif-latin); font-weight: 400; color: var(--ink-faint); margin-left: 6px; }
.defs__body { color: var(--ink-soft); font-size: 0.92rem; margin-top: 4px; }

/* ---------- original text ---------- */
.original {
  margin-top: clamp(30px, 4vw, 56px);
  padding: clamp(56px, 7vw, 96px) 0 clamp(50px, 6vw, 84px);
  background: var(--paper-white);
}
.original__head { padding-bottom: clamp(26px, 3vw, 42px); }
.original__note {
  font-size: 0.86rem;
  line-height: 1.85;
  color: var(--ink-soft);
}
.original__note p + p { margin-top: 0.9em; }
.original__tools { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.original__grid {
  display: grid;
  grid-template-columns: var(--axis) calc(100% - var(--axis));
  align-items: start;
  position: relative;
}
.gloss-column { position: relative; padding-right: clamp(22px, 3.4vw, 58px); }
.margin-index { margin-bottom: 26px; }
.margin-index ol { list-style: none; }
.margin-index li { margin: 2px 0; }
.margin-index a {
  display: block;
  padding: 4px 0 4px 12px;
  border-left: 2px solid transparent;
  font-size: 0.82rem;
  line-height: 1.55;
  color: var(--ink-faint);
  text-decoration: none !important;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}
.margin-index a:hover { color: var(--ink); }
.margin-index a.is-active { color: var(--rubric); border-left-color: var(--rubric); }
.margin-index__fac {
  margin-top: 12px;
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.12em;
  color: var(--ink-faint);
}
.gloss { position: absolute; left: 0; right: clamp(22px, 3.4vw, 58px); }
.gloss__no {
  font-family: var(--serif-display);
  font-size: 1.05rem;
  color: var(--rubric);
  line-height: 1;
}
.gloss__title {
  font-size: 0.94rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin-top: 3px;
  line-height: 1.6;
}
.gloss__body {
  margin-top: 6px;
  font-size: 0.86rem;
  line-height: 1.85;
  color: var(--ink-soft);
}
.gloss__body p { margin-bottom: 0.5em; }
.gloss.is-active .gloss__title { color: var(--rubric); }
.gloss.is-active .gloss__body { color: var(--ink); }
.gloss__link { color: inherit; }
.gloss__link:hover { color: var(--rubric); }

.paper-text {
  position: relative;
  min-width: 0;
  font-family: var(--serif-latin);
  font-size: clamp(1.03rem, 1.1vw, 1.12rem);
  line-height: 1.72;
  color: var(--ink);
  max-width: 41rem;
}
.paper-text p { margin-bottom: 1.05em; }
.paper-text .ltx_para { margin-bottom: 1.05em; min-width: 0; max-width: 100%; overflow-x: auto; }
.paper-text .ltx_para p { margin-bottom: 0; }
.paper-text h2,
.paper-text h3,
.paper-text h4,
.paper-text h5 {
  scroll-margin-top: calc(var(--topbar-h) + 20px);
  font-family: var(--serif-display);
  font-weight: 600;
  letter-spacing: 0.005em;
  line-height: 1.2;
  margin: 1.9em 0 0.6em;
  color: var(--ink);
}
.paper-text h2 { font-size: 1.7rem; }
.paper-text h3 { font-size: 1.35rem; }
.paper-text h4 { font-size: 1.12rem; }
.paper-text h5 { font-size: 1.02rem; font-family: var(--serif-latin); letter-spacing: 0.02em; }
.paper-text h6 { font-size: 0.95rem; font-family: var(--serif-latin); margin: 1.4em 0 0.5em; }
.paper-text ul, .paper-text ol { margin: 0 0 1.1em 1.3em; }
.paper-text li { margin-bottom: 0.35em; }
.paper-text figure { margin: 2.2em 0; }
.paper-text figure img,
.paper-text object { width: 100%; height: auto; display: block; }
.paper-text figcaption,
.paper-text .ltx_caption {
  font-family: var(--serif-cn);
  font-size: 0.82rem;
  line-height: 1.75;
  color: var(--ink-faint);
  margin-top: 10px;
}
.paper-text figcaption .ltx_tag,
.paper-text .ltx_caption .ltx_tag { color: var(--rubric); font-weight: 600; }
.paper-text table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.8em 0;
  font-size: 0.84rem;
  line-height: 1.5;
}
.paper-text th, .paper-text td {
  border-bottom: 1px solid color-mix(in srgb, var(--ink) 16%, transparent);
  padding: 8px 10px 8px 0;
  text-align: left;
  vertical-align: top;
}
.paper-text th { border-bottom-color: color-mix(in srgb, var(--ink) 40%, transparent); }
.paper-text .ltx_table { overflow-x: auto; }
.paper-body { min-width: 0; }
.paper-text .ltx_equation,
.paper-text .ltx_eqn_table,
.paper-text .ltx_eqn_align,
.paper-text .ltx_para > math,
.paper-text .ltx_table { max-width: 100%; overflow-x: auto; }
.paper-text math[display="block"] { display: block; max-width: 100%; overflow-x: auto; }
.paper-text .ltx_table { overflow-x: auto; }
.paper-text .ltx_table table { min-width: 0; }
.paper-text .ltx_bibliography { font-size: 0.86rem; }
.paper-text .ltx_bibitem { margin-bottom: 0.85em; padding-left: 2.2em; text-indent: -2.2em; line-height: 1.6; }
.paper-text .ltx_tag_bibitem { color: var(--ink-faint); margin-right: 4px; }
.paper-text .ltx_cite { white-space: nowrap; }
.paper-text .ltx_note_mark { color: var(--rubric); }
.paper-text a { color: inherit; }
.paper-text .ltx_ERROR { color: var(--rubric); }

math { font-family: var(--math); font-size: 1.02em; }
.paper-text mtext, .paper-text mi, .paper-text mn, .paper-text mo { font-family: var(--math); }

sup.fn {
  color: var(--rubric);
  font-family: var(--serif-latin);
  font-size: 0.68em;
  cursor: pointer;
  padding: 0 1px;
}
sup.fn:hover { text-decoration: underline; }
.footnotes {
  margin-top: 2.4em;
  padding: 22px 26px;
  background: var(--ground-2);
  font-size: 0.81rem;
  line-height: 1.75;
  color: var(--ink-soft);
}
.footnotes p { margin-bottom: 0.6em; }
.footnotes .fn-mark { color: var(--rubric); margin-right: 4px; }

/* ---------- gloss marks & inline notes ---------- */
.gloss-mark {
  display: inline-block;
  margin-left: 3px;
  font-family: var(--serif-display);
  font-size: 0.78em;
  line-height: 1;
  color: var(--rubric);
  vertical-align: super;
  cursor: pointer;
  text-decoration: underline dotted;
  text-decoration-color: color-mix(in srgb, var(--rubric) 55%, transparent);
  text-underline-offset: 2px;
  padding: 0 1px;
  transition: background 160ms var(--ease);
}
.gloss-mark:hover, .gloss-mark.is-active { background: var(--rubric); color: var(--paper-white); }
.para-flash { background: color-mix(in srgb, var(--gold) 22%, transparent); transition: background 600ms var(--ease); }
.inline-gloss {
  display: none;
}
.inline-gloss summary {
  cursor: pointer;
  color: var(--rubric);
  font-size: 0.82rem;
  letter-spacing: 0.04em;
}
.inline-gloss summary strong { color: var(--ink); font-weight: 600; }
.inline-gloss__body { margin-top: 8px; line-height: 1.85; color: var(--ink-soft); }
.inline-gloss__body p { margin-bottom: 0.5em; }

/* mobile fallback: hide absolute gloss layer */
.gloss-column.is-mobile { display: none; }

/* ---------- exercises ---------- */
.exercises {
  margin-top: clamp(56px, 7vw, 100px);
  padding: clamp(40px, 5vw, 64px) 0;
  background: var(--ground-2);
}
.quiz { list-style: none; }
.quiz-item { padding: 34px 0; }
.quiz-item + .quiz-item { padding-top: 10px; }
.quiz-q { display: flex; gap: 14px; align-items: baseline; }
.quiz-no {
  font-family: var(--serif-display);
  color: var(--rubric);
  font-size: 1.05rem;
  flex: 0 0 auto;
  line-height: 1.4;
}
.quiz-stem { font-size: 1.01rem; line-height: 1.85; font-weight: 500; }
.quiz-type {
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-left: 8px;
  white-space: nowrap;
}
.quiz-options { list-style: none; margin: 16px 0 0 2.1em; display: grid; gap: 8px; }
.quiz-option {
  display: flex;
  gap: 12px;
  align-items: baseline;
  width: 100%;
  text-align: left;
  padding: 12px 16px;
  background: var(--ground-2);
  font-size: 0.95rem;
  line-height: 1.7;
  transition: background 160ms var(--ease);
}
.quiz-option:hover { background: var(--ground-3); }
.quiz-option .letter {
  font-family: var(--serif-display);
  color: var(--ink-faint);
  flex: 0 0 auto;
  font-size: 1rem;
}
.quiz-option.is-correct { background: color-mix(in srgb, var(--verdigris) 18%, var(--ground)); }
.quiz-option.is-wrong { background: color-mix(in srgb, var(--rubric) 14%, var(--ground)); }
.quiz-option.is-correct .letter { color: var(--verdigris); }
.quiz-option.is-wrong .letter { color: var(--rubric); }
.quiz-feedback {
  margin: 14px 0 0 2.1em;
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--ink-soft);
}
.quiz-feedback .verdict { font-weight: 600; }
.quiz-feedback .verdict.ok { color: var(--verdigris); }
.quiz-feedback .verdict.no { color: var(--rubric); }
.quiz-short { margin: 16px 0 0 2.1em; }
.quiz-short textarea {
  width: 100%;
  min-height: 120px;
  padding: 14px 16px;
  background: var(--ground-2);
  border: 0;
  border-bottom: 2px solid color-mix(in srgb, var(--ink) 25%, transparent);
  font-family: var(--serif-cn);
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--ink);
  resize: vertical;
}
.quiz-short textarea:focus { outline: none; border-bottom-color: var(--rubric); background: var(--paper-white); }
.quiz-short__bar { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin-top: 12px; }
.quiz-short__count { font-family: var(--serif-latin); font-size: 0.82rem; color: var(--ink-faint); letter-spacing: 0.08em; }
.quiz-reference { margin-top: 14px; font-size: 0.9rem; line-height: 1.85; color: var(--ink-soft); }
.quiz-reference__label { font-size: 0.82rem; letter-spacing: 0.16em; color: var(--rubric); text-transform: uppercase; margin-bottom: 4px; }
.quiz-progress {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 28px;
  font-size: 0.86rem;
  color: var(--ink-soft);
}
.quiz-progress__bar { flex: 1; height: 2px; background: var(--ground-3); }
.quiz-progress__bar span { display: block; height: 100%; background: var(--rubric); width: 0; transition: width 300ms var(--ease); }
.quiz-done {
  margin-top: 18px;
  padding: 18px 22px;
  background: color-mix(in srgb, var(--verdigris) 12%, var(--ground));
  font-size: 0.92rem;
  line-height: 1.8;
  display: none;
}
.quiz-done.is-visible { display: block; }

/* ---------- part foot ---------- */
.part-foot {
  margin-top: clamp(60px, 8vw, 110px);
  padding-top: 8px;
  display: grid;
  grid-template-columns: var(--axis) calc(100% - var(--axis));
}
.part-foot__body { display: flex; flex-wrap: wrap; gap: 18px 28px; align-items: center; justify-content: space-between; }
.part-foot__links { display: flex; gap: 26px; flex-wrap: wrap; }
.part-foot__link { font-size: 0.9rem; color: var(--ink-soft); }
.part-foot__link:hover { color: var(--rubric); }
.part-foot__link span { display: block; font-size: 0.82rem; letter-spacing: 0.16em; color: var(--ink-faint); margin-bottom: 4px; }
.mark-read.is-done { background: var(--verdigris); }
.mark-read.is-done:hover { background: var(--verdigris); }
.part-foot__next { text-align: right; }

/* ---------- chat view ---------- */
.chat-page { padding-top: clamp(48px, 6vw, 84px); padding-bottom: clamp(70px, 9vw, 120px); }
.chat-head h1 {
  font-family: var(--serif-cn);
  font-size: clamp(1.9rem, 3.2vw, 2.6rem);
  font-weight: 600;
  letter-spacing: 0.05em;
}
.chat-head p { margin-top: 1rem; color: var(--ink-soft); max-width: 38em; line-height: 2; }
#chat-root { margin-top: clamp(30px, 4vw, 48px); }
body[data-view="chat"] .chat-page { padding-top: clamp(18px, 2.6vw, 34px); padding-bottom: 40px; }
body[data-view="chat"] .chat-head h1 { font-size: clamp(1.55rem, 2vw, 1.9rem); }
body[data-view="chat"] .chat-head p { margin-top: 0.55rem; max-width: 62em; font-size: 0.9rem; line-height: 1.75; }
body[data-view="chat"] #chat-root { margin-top: 22px; }
body[data-view="chat"] .chat-log { height: clamp(300px, calc(100svh - 500px), 620px); }
@media (max-width: 900px) {
  body[data-view="chat"] .chat-log { height: clamp(300px, 52svh, 460px); }
}

/* ---------- facsimile ---------- */
.fac-page h1 { font-family: var(--serif-cn); font-size: var(--fs-title); font-weight: 600; letter-spacing: 0.05em; }
.fac-page__lead { margin-top: 1.1rem; color: var(--ink-soft); max-width: 38em; line-height: 2; }
.fac-grid {
  margin-top: clamp(36px, 5vw, 64px);
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
  gap: clamp(16px, 2vw, 28px);
}
.fac-item { display: block; text-align: left; }
.fac-item img {
  width: 100%;
  background: #fff;
  transition: opacity 180ms var(--ease);
}
.fac-item:hover img { opacity: 0.85; }
.fac-item__label {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  margin-top: 8px;
  font-size: 0.82rem;
  color: var(--ink-faint);
  font-family: var(--serif-latin);
  letter-spacing: 0.08em;
}
.fac-item__label b { color: var(--ink-soft); font-weight: 500; }

/* ---------- lightbox ---------- */
.lightbox {
  width: min(96vw, 1100px);
  max-height: 94svh;
  padding: 0;
  background: var(--paper-white);
  border: 0;
  color: var(--ink);
}
.lightbox::backdrop { background: rgba(20, 18, 14, 0.82); }
.lightbox__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 18px;
  background: var(--ground-2);
}
.lightbox__title { font-size: 0.82rem; letter-spacing: 0.12em; color: var(--ink-soft); }
.lightbox__close { font-size: 0.82rem; letter-spacing: 0.12em; color: var(--rubric); }
.lightbox__body { overflow: auto; max-height: calc(94svh - 48px); padding: 18px; }
.lightbox__body img { display: block; margin: 0 auto; max-width: 100%; }

/* ---------- footer ---------- */
.footer {
  margin-top: clamp(80px, 10vw, 150px);
  background: var(--night);
  color: var(--night-ink);
  padding: clamp(60px, 8vw, 110px) 0 30px;
}
.footer__inner { max-width: 1440px; margin-inline: auto; padding-inline: var(--gutter); }
.footer__wordmark {
  font-family: var(--serif-display);
  font-size: clamp(4rem, 12vw, 11rem);
  font-weight: 600;
  line-height: 0.82;
  letter-spacing: -0.03em;
  color: var(--night-soft);
  margin-bottom: clamp(40px, 6vw, 80px);
}
.footer__wordmark span {
  font-family: var(--serif-cn);
  font-size: 0.16em;
  letter-spacing: 0.34em;
  color: var(--night-soft);
  margin-left: 0.6em;
  vertical-align: 0.55em;
}
.footer__cols {
  display: grid;
  grid-template-columns: 1.4fr 0.7fr 1.1fr;
  gap: clamp(28px, 5vw, 80px);
  max-width: 1200px;
}
.footer__label {
  font-family: var(--serif-latin);
  font-size: 0.82rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 14px;
}
.footer__col p { font-size: 1rem; line-height: 1.9; color: var(--night-soft); max-width: 42em; }
.footer__col a { color: var(--night-ink); text-decoration: underline; text-underline-offset: 3px; text-decoration-color: color-mix(in srgb, var(--gold) 60%, transparent); }
.footer__col a:hover { color: var(--gold); }
.footer__links { display: flex; flex-direction: column; gap: 4px; }
.footer__fine { margin-top: 12px; font-size: 0.85rem !important; color: #a49b86 !important; }
.footer__base {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 32px;
  justify-content: space-between;
  align-items: center;
  margin-top: clamp(60px, 8vw, 100px);
  padding-top: 22px;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
  color: #a49b86;
}
.footer__base a { color: var(--night-soft); }
.footer__base a:hover { color: var(--gold); }

/* ---------- toast ---------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  transform: translate(-50%, 16px);
  z-index: 300;
  background: var(--ink);
  color: var(--ground);
  padding: 12px 22px;
  font-size: 0.88rem;
  letter-spacing: 0.04em;
  opacity: 0;
  pointer-events: none;
  transition: opacity 220ms var(--ease), transform 220ms var(--ease);
}
.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }

/* ---------- motion ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.js .reveal.is-in { opacity: 1; transform: none; }
.js .mask-line { display: block; overflow: hidden; }
.js .mask-line > span {
  display: block;
  transform: translateY(110%);
  transition: transform 900ms var(--ease);
}
.js .cover.is-ready .mask-line > span { transform: none; }
.js .cover.is-ready .mask-line:nth-child(2) > span { transition-delay: 110ms; }
.js .cover.is-ready .cover__cn,
.js .cover.is-ready .cover__authors { animation: fade-up 700ms var(--ease) 380ms both; }
.js .cover.is-ready .cover__left { animation: fade-up 700ms var(--ease) 520ms both; }
.js .cover.is-ready .cover__colophon { animation: fade-up 800ms var(--ease) 80ms both; }
.js .cover.is-ready .cover__plate { animation: fade-up 900ms var(--ease) 220ms both; }
.js .cover.is-ready .cover__hint { animation: fade-up 700ms var(--ease) 680ms both; }
.js .cover.is-ready .seal { animation: seal-in 760ms var(--ease) 560ms both; }
@keyframes seal-in {
  from { opacity: 0; transform: scale(0.84); }
  to { opacity: 1; transform: scale(1); }
}
@keyframes fade-up {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-delay: 0ms !important;
    transition-duration: 0.001ms !important;
  }
  .js .reveal { opacity: 1; transform: none; }
  .js .mask-line > span { transform: none; }
}

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  :root { --axis: 40%; }
  .spread__body, .paper-text { max-width: 36rem; }
}
@media (max-width: 880px) {
  .nav { display: none; }
  .nav.is-open {
    display: flex;
    position: absolute;
    top: var(--topbar-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--ground-2);
    padding: 10px var(--gutter) 20px;
    z-index: 90;
  }
  .nav.is-open .nav__link { padding: 14px 0; width: 100%; font-size: 1rem; }
  .nav-toggle { display: block; }
  .wordmark { margin-right: 0; }
  .spread,
  .cover__grid,
  .chapter,
  .original__grid,
  .part-foot {
    grid-template-columns: minmax(0, 1fr);
  }
  .spread__margin { padding-right: 0; margin-bottom: 26px; }
  .lesson-aside { position: static; max-width: none; }
  .cover { min-height: auto; padding-top: 90px; }
  .cover__colophon { display: none; }
  .cover__plate { position: static; width: 190px; margin: 0; order: 3; }
  .cover__plate-frame { padding: 8px; }
  .cover__grid { order: 2; }
  .plates__head { grid-template-columns: minmax(0, 1fr); gap: 10px; }
  .plates__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .plates__frame { height: 180px; }
  .cover__left { margin-top: 44px; padding-right: 0; }
  .cover__left { order: 2; }
  .cover__title { font-size: clamp(2.6rem, 11.5vw, 4.4rem); }
  .cover__authors { display: none; }
  .chapter { padding: 22px 0; }
  .chapter__no { margin-bottom: 6px; }
  .part-no { display: none; }
  .gloss-column { display: none; }
  .inline-gloss {
    display: block;
    margin: 0 0 1.4em;
    background: var(--ground-2);
    padding: 12px 16px;
    font-size: 0.9rem;
  }
  .original { padding-top: 46px; }
  .paper-text { max-width: none; }
  .footer__cols { grid-template-columns: 1fr; }
  .footer__wordmark { font-size: 17vw; }
  .quiz-options, .quiz-feedback, .quiz-short { margin-left: 0; }
  .quiz-q { gap: 10px; }
}
@media (max-width: 520px) {
  :root { --fs-body: 1.02rem; --gutter: 20px; }
  .cover__title { font-size: 11.5vw; }
  .cover__title .mask-line > span { white-space: normal; }
  .cover__cn { letter-spacing: 0.14em; }
  .part-head h1 { font-size: 1.7rem; }
  .paper-text { font-size: 1rem; }
  .part-meta { font-size: 0.82rem; }
  .btn { width: 100%; }
  .cover__actions { align-items: stretch; }
}
/* =========================================================
   Mobile polish — chat order, touch targets, small screens
   ========================================================= */
@media (max-width: 900px) {
  #chat-root .chat-main { order: 1; }
  #chat-root .chat-aside { order: 2; padding-top: 6px; }
  #chat-root .chat-shell { gap: 26px; }
  #chat-root .chat-log { height: clamp(300px, 46svh, 430px); }
  #chat-root .chat-composer {
    position: sticky;
    bottom: 0;
    z-index: 6;
    background: var(--ground);
    padding-top: 8px;
  }
  #chat-root .chat-btn { min-height: 44px; }
  #chat-root .chat-settings__summary { min-height: 44px; align-items: center; }
}
@media (max-width: 700px) {
  body[data-view="chat"] .chat-page { padding-top: 12px; }
  body[data-view="chat"] .chat-head h1 { font-size: 1.5rem; }
  body[data-view="chat"] .chat-head p { display: none; }
  body[data-view="chat"] #chat-root { margin-top: 14px; }

  .text-link { display: inline-flex; align-items: center; min-height: 40px; }
  .inline-gloss summary { padding: 10px 0; }
  .footer__links a { display: flex; align-items: center; min-height: 40px; }
  .footer__base a { display: inline-flex; align-items: center; min-height: 40px; }
  .nav__link { min-height: 44px; display: flex; align-items: center; }
  .wordmark__cn { font-size: 0.8rem; }
  .topbar__inner { height: 60px; }
  :root { --topbar-h: 60px; }

  .w-widget { font-size: 13px; }
  .w-widget .w-kicker,
  .w-widget .w-hint,
  .w-widget .w-note,
  .w-widget .w-tag,
  .w-widget .w-caption { font-size: 12px; }
  .w-widget button { min-height: 38px; }

  .table-hint {
    margin: 10px 0 2px;
    font-size: 0.82rem;
    letter-spacing: 0.03em;
    color: var(--rubric);
  }
  .paper-text .ltx_table { scrollbar-width: thin; }
  .paper-text .ltx_table::-webkit-scrollbar { height: 6px; }
  .paper-text .ltx_table::-webkit-scrollbar-thumb { background: color-mix(in srgb, var(--ink) 35%, transparent); }
}
@media (max-width: 380px) {
  .cover__title { font-size: 11vw; }
  .cover__cn { letter-spacing: 0.1em; font-size: 1.02rem; }
  .part-head h1 { font-size: 1.55rem; }
}

@media (max-width: 880px) {
  .lesson-aside { position: static; margin-bottom: 4px; }
  .lesson-aside .running-head,
  .lesson-aside__no,
  .lesson-aside__title,
  .lesson-aside__meta { display: none; }
  .lesson-aside__note { margin-top: 0; font-size: 0.92rem; }
  .lesson-aside__back { margin-top: 10px; }
}
@media (max-width: 700px) {
  #chat-root .chat-suggestions { grid-template-columns: minmax(0, 1fr); }
  #chat-root .chat-suggestion { min-height: 0; }
  .chat-grade .chat-btn { min-height: 44px; }
}
@media (max-width: 700px) {
  body .w-widget { font-size: 13px; }
  body .w-widget .w-kicker,
  body .w-widget .w-hint,
  body .w-widget .w-note,
  body .w-widget .w-tag,
  body .w-widget .w-caption { font-size: 12px; }
  body .w-widget button { min-height: 40px; }
}
/* table scroll hint, all widths */
.table-hint {
  margin: 8px 0 2px;
  font-size: 0.82rem;
  letter-spacing: 0.03em;
  color: var(--rubric);
}
@media (max-width: 700px) {
  .wrap,
  .topbar__inner,
  .footer__inner {
    padding-left: max(var(--gutter), env(safe-area-inset-left));
    padding-right: max(var(--gutter), env(safe-area-inset-right));
  }
  body { -webkit-tap-highlight-color: transparent; }
}