:root {
  color-scheme: light;
  --ink: #1d2440;
  --ink-soft: #616b86;
  --ink-faint: #697386;
  --line: #e7eaf2;
  --line-strong: #1d2440;
  --paper: #ffffff;
  --canvas: #f4f6fa;
  --accent: #5266db;
  --accent-deep: #3f52c3;
  --accent-pale: #eef0ff;
  --lilac: #f4f1ff;
  --mint: #eaf8f3;
  --radius: 18px;
  --content-width: 1280px;
  --sidebar-width: 248px;
  --sidebar-width-collapsed: 76px;
  font-family: "Avenir Next", "Segoe UI", system-ui, -apple-system, sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }

html { overflow-x: clip; scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  background: var(--canvas);
  color: var(--ink);
  font-size: 15px;
  line-height: 1.5;
}

body.menu-open { overflow: hidden; position: fixed; width: 100%; }

a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; touch-action: manipulation; }
button { font: inherit; }
button:disabled { cursor: not-allowed; opacity: .58; }

.skip-link {
  background: var(--ink);
  border-radius: 0 0 9px 0;
  color: var(--paper);
  font-size: 13px;
  font-weight: 750;
  left: 0;
  padding: 10px 14px;
  position: fixed;
  top: 0;
  transform: translateY(-120%);
  transition: transform .2s ease;
  z-index: 100;
}
.skip-link:focus { transform: translateY(0); }

.icon-button {
  align-items: center;
  background: transparent;
  border: 0;
  border-radius: 9px;
  color: var(--ink-soft);
  cursor: pointer;
  display: inline-flex;
  height: 44px;
  justify-content: center;
  padding: 0;
  width: 44px;
}
.icon-button:hover { background: #f3f5fb; color: var(--ink); }

:focus-visible {
  outline: 3px solid #99a7ff;
  outline-offset: 3px;
}

.app-shell { min-height: 100dvh; }

.sidebar {
  background: var(--paper);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  height: 100dvh;
  left: 0;
  padding: 28px 18px 20px;
  position: fixed;
  top: 0;
  transition: width .2s ease;
  width: var(--sidebar-width);
  z-index: 20;
}

.sidebar__top { align-items: center; display: flex; justify-content: space-between; margin: 0 10px 50px; }
.sidebar__actions { align-items: center; display: flex; gap: 4px; }
.brand { align-items: center; display: inline-flex; gap: 10px; letter-spacing: -.04em; }
.brand-mark { display: inline-flex; gap: 3px; height: 22px; transform: rotate(-12deg); width: 22px; }
.brand-mark span { background: var(--accent); border-radius: 3px; display: block; width: 9px; }
.brand-mark span:first-child { height: 15px; margin-top: 7px; opacity: .62; }
.brand-mark span:last-child { height: 21px; }
.brand-name { font-size: 20px; font-weight: 750; }
.brand-name span { color: var(--accent); }
.sidebar__collapse { font-size: 24px; line-height: 1; width: 30px; }
.sidebar__close, .menu-toggle { display: none; }

.nav-label, .eyebrow, .tip-card__eyebrow {
  color: var(--ink-faint);
  font-size: 10px;
  font-weight: 750;
  letter-spacing: .14em;
  margin: 0 10px 12px;
  text-transform: uppercase;
}

.zh-hint {
  color: var(--ink-faint);
  display: block;
  font-size: .78em;
  font-weight: 500;
  letter-spacing: 0;
  line-height: 1.4;
  margin-top: 2px;
  text-transform: none;
}
.eyebrow .zh-hint { color: var(--ink-soft); font-size: 1em; }
h1 > .zh-hint { font-size: .25em; letter-spacing: 0; line-height: 1.35; margin-top: 9px; }
.level-state .zh-hint { color: currentColor; font-size: 9px; opacity: .78; }
.text-link .zh-hint { display: inline; font-size: 10px; margin-left: 5px; }
.button .zh-hint { color: #fff; display: inline; font-size: 10px; margin-left: 6px; }
.button--secondary .zh-hint { color: currentColor; }
.vocab-card__state .zh-hint { font-size: 10px; }
.vocab-card__plural .zh-hint { display: inline; font-size: 10px; margin-left: 5px; }
.exercise-card > .zh-hint, .lesson-heading > .zh-hint, .backup-section > .zh-hint { margin-bottom: 10px; }

.nav-group { display: grid; gap: 4px; }
.nav-link { align-items: center; border-radius: 10px; color: var(--ink-soft); display: flex; font-size: 14px; font-weight: 600; gap: 13px; padding: 11px 12px; transition: background .2s ease, color .2s ease; }
.nav-link__copy { display: grid; gap: 1px; line-height: 1.2; }
.nav-link__copy .zh-hint { font-size: 10px; }
.nav-link:hover { background: #f7f8fc; color: var(--ink); }
.nav-link.is-active { background: var(--accent-pale); color: var(--accent-deep); }
.nav-icon { align-items: center; color: currentColor; display: inline-flex; font-size: 17px; font-weight: 700; height: 20px; justify-content: center; line-height: 1; width: 20px; }
.nav-link:nth-of-type(3) .nav-icon { font-size: 12px; letter-spacing: -.08em; }
.sidebar__bottom { margin-top: auto; }
.tip-card { background: var(--lilac); border-radius: 14px; margin: 0 3px 24px; overflow: hidden; padding: 16px 16px 14px; position: relative; }
.tip-card__eyebrow { color: var(--accent-deep); margin: 0 0 6px; }
.tip-card p { color: #535d81; font-size: 12px; line-height: 1.45; margin: 0; max-width: 160px; }
.tip-card__line { background: var(--accent); bottom: 0; height: 3px; left: 0; opacity: .7; position: absolute; width: 42%; }
.profile-chip { align-items: center; border-top: 1px solid var(--line); display: flex; gap: 10px; padding: 18px 8px 0; }
.avatar { align-items: center; background: #dfe4ff; border: 0; border-radius: 50%; color: var(--accent-deep); display: inline-flex; flex: 0 0 auto; font-size: 12px; font-weight: 800; height: 34px; justify-content: center; width: 34px; }
.profile-chip__copy { display: grid; gap: 1px; min-width: 0; }
.profile-chip__copy strong { font-size: 12px; }
.profile-chip__copy small { color: var(--ink-faint); font-size: 11px; }
.profile-chip__chevron { color: var(--ink-faint); font-size: 16px; letter-spacing: 1px; margin-left: auto; }

@media (min-width: 701px) {
.sidebar { display: none; }
.sidebar-scrim { display: none; }
body.sidebar-collapsed {
  --sidebar-width: var(--sidebar-width-collapsed);
}
body.sidebar-collapsed .sidebar {
  padding-left: 10px;
  padding-right: 10px;
}
body.sidebar-collapsed .sidebar__top {
  gap: 4px;
  margin-left: 0;
  margin-right: 0;
}
body.sidebar-collapsed .sidebar .brand { gap: 0; }
body.sidebar-collapsed .sidebar .brand-name,
body.sidebar-collapsed .sidebar .nav-label,
body.sidebar-collapsed .sidebar .nav-link__copy,
body.sidebar-collapsed .sidebar .tip-card,
body.sidebar-collapsed .sidebar .profile-chip__copy,
body.sidebar-collapsed .sidebar .profile-chip__chevron { display: none; }
body.sidebar-collapsed .sidebar__actions { gap: 0; }
body.sidebar-collapsed .sidebar__collapse { transform: rotate(180deg); }
body.sidebar-collapsed .nav-link {
  gap: 0;
  justify-content: center;
  padding-left: 8px;
  padding-right: 8px;
}
body.sidebar-collapsed .nav-icon { width: 24px; }
body.sidebar-collapsed .profile-chip {
  justify-content: center;
  padding-left: 0;
  padding-right: 0;
}
}

.main-content { margin-left: 0; min-height: 100dvh; }
.topbar { background: var(--paper); border-bottom: 1px solid var(--line); padding: 0 clamp(24px, 4vw, 62px); position: sticky; top: 0; z-index: 10; }
.topbar__utility { align-items: center; display: grid; grid-template-columns: minmax(44px, 1fr) auto minmax(44px, 1fr); height: 64px; margin: 0 auto; max-width: var(--content-width); }
.topbar__utility > .menu-toggle { grid-column: 1; grid-row: 1; justify-self: start; }
.topbar__brand { align-items: center; color: var(--ink); display: inline-flex; gap: 8px; grid-column: 2; grid-row: 1; justify-self: center; letter-spacing: 0; }
.topbar__brand-word { display: inline-flex; gap: 2px; }
.topbar__brand-tile { align-items: center; background: var(--ink); color: var(--paper); display: inline-flex; font-size: 15px; font-weight: 800; height: 27px; justify-content: center; line-height: 1; width: 25px; }
.topbar__nav { align-items: stretch; border-bottom: 1px solid var(--line); border-top: 1px solid var(--line); display: flex; gap: clamp(30px, 4vw, 54px); justify-content: center; margin: 0 auto; max-width: var(--content-width); min-height: 46px; }
.topbar__nav-link { align-items: baseline; color: var(--ink-soft); display: inline-flex; font-size: 15px; font-weight: 700; gap: 6px; justify-content: center; line-height: 1.15; padding: 15px 1px 13px; position: relative; }
.topbar__nav-link .zh-hint { display: inline; font-size: 11px; line-height: 1.15; margin: 0; }
.topbar__nav-link::after { background: var(--accent); bottom: -1px; content: ""; height: 2px; left: 0; position: absolute; right: 0; transform: scaleX(0); transition: transform .2s ease; }
.topbar__nav-link:hover, .topbar__nav-link.is-active { color: var(--ink); }
.topbar__nav-link.is-active::after { transform: scaleX(1); }
.topbar__context { align-items: center; display: grid; gap: 18px; grid-template-columns: 1fr auto; margin: 0 auto; max-width: var(--content-width); min-height: 34px; }
.topbar__level-nav { align-items: center; display: flex; gap: clamp(20px, 2.6vw, 36px); min-height: 34px; min-width: 0; overflow-x: auto; scrollbar-width: none; }
.topbar__level-nav::-webkit-scrollbar { display: none; }
.topbar__level-nav a { color: var(--ink-soft); font-size: 12px; font-weight: 700; line-height: 1; white-space: nowrap; }
.topbar__level-nav a:hover { color: var(--accent-deep); }
.breadcrumbs { align-items: center; color: var(--ink); display: flex; font-size: 12px; gap: 10px; }
.breadcrumbs__muted { color: var(--ink-faint); }
.breadcrumbs__muted .zh-hint, .breadcrumbs__zh { font-size: 10px; }
.topbar__actions { align-items: center; display: flex; gap: 16px; grid-column: 3; grid-row: 1; justify-self: end; }
.topbar__language, .topbar__locale { color: var(--ink-soft); font-size: 12px; line-height: 1.2; white-space: nowrap; }
.topbar__language strong { color: var(--accent-deep); }
.topbar__locale strong { color: var(--accent-deep); }
.streak { align-items: center; color: var(--ink-soft); display: flex; font-size: 12px; gap: 8px; line-height: 1.15; }
.streak strong { color: var(--ink); }
.streak__dot { background: #e3a54d; border-radius: 50%; height: 7px; width: 7px; }
.streak > span:last-child { display: grid; gap: 2px; }
.streak .zh-hint { font-size: 10px; line-height: 1; margin: 0; }
.avatar--small { cursor: pointer; height: 44px; width: 44px; }

@media (min-width: 901px) {
  .topbar__context { display: block; }
  .topbar__level-nav { justify-content: center; }
  .topbar__context > .breadcrumbs { display: none; }
}

.page-wrap { background: var(--paper); margin: 0 auto; max-width: var(--content-width); min-height: calc(100dvh - 144px); padding: 34px clamp(24px, 4vw, 62px) 46px; }
:where(.page-wrap, section)[id] { scroll-margin-top: 88px; }
h1, h2, h3, p { margin-top: 0; }
h1 { font-size: clamp(37px, 4.5vw, 60px); letter-spacing: -.065em; line-height: 1.02; margin: 0; max-width: 650px; }
h1 em { color: var(--accent); font-style: normal; }

.learning-section { margin-bottom: 57px; }
.section-heading { align-items: end; display: flex; justify-content: space-between; margin-bottom: 21px; }
.section-heading .eyebrow { margin: 0 0 8px; }
.section-heading h2 { font-size: 24px; letter-spacing: -.045em; line-height: 1.12; margin: 0; }
.level-label { color: var(--accent-deep); font-size: 12px; font-weight: 800; letter-spacing: .08em; }
.level-state { align-items: flex-start; background: var(--accent-pale); border-radius: 100px; color: var(--accent-deep); display: inline-flex; flex-direction: column; font-size: 10px; font-weight: 700; line-height: 1.25; padding: 5px 9px; vertical-align: top; }
.text-link { align-items: center; color: var(--accent-deep); display: inline-flex; font-size: 12px; font-weight: 750; min-height: 44px; white-space: nowrap; }
.text-link span { display: inline-block; font-size: 17px; line-height: 0; margin-left: 4px; transition: transform .2s ease; }
.text-link:hover span { transform: translateX(3px); }

.button { align-items: center; background: var(--accent); border: 0; border-radius: 9px; color: white; cursor: pointer; display: inline-flex; font-size: 12px; font-weight: 750; justify-content: center; min-height: 44px; padding: 0 14px; transition: background .2s ease, transform .2s ease; }
.button:hover { background: var(--accent-deep); }
.button:active { transform: translateY(1px); }
.toast { background: var(--ink); border-radius: 10px; bottom: 22px; color: white; font-size: 12px; left: 50%; opacity: 0; padding: 10px 15px; pointer-events: none; position: fixed; transform: translate(-50%, 8px); transition: opacity .2s ease, transform .2s ease; z-index: 50; }
.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }

.learning-hero { margin-bottom: 42px; max-width: 720px; }
.learning-hero h1, .lesson-heading h1 { margin: 0; }
.learning-hero > p:last-child, .lesson-heading > p:last-child { color: var(--ink-soft); line-height: 1.65; max-width: 620px; }
.lesson-heading h1 + p { color: var(--ink-soft); line-height: 1.65; max-width: 620px; }
.learning-summary { background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius); display: grid; grid-template-columns: repeat(3, 1fr); margin-bottom: 54px; overflow: hidden; }
.learning-summary > div { display: grid; gap: 2px; padding: 20px 22px; }
.learning-summary > div + div { border-left: 1px solid var(--line); }
.learning-summary strong { font-size: 25px; letter-spacing: -.05em; }
.learning-summary span { color: var(--ink-soft); font-size: 12px; }
.learning-card-grid, .vocabulary-grid { display: grid; gap: 18px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.continue-card { align-items: center; background: var(--accent-pale); border: 1px solid #dbe0ff; border-radius: var(--radius); display: flex; gap: 24px; justify-content: space-between; margin: 0 0 46px; max-width: 760px; padding: 22px; }
.continue-card h2 { font-size: 24px; letter-spacing: -.045em; margin: 0 0 4px; }
.continue-card p { color: var(--ink-soft); font-size: 13px; margin: 0; }
.continue-card .eyebrow { color: var(--accent-deep); margin-bottom: 7px; }
.continue-card--complete { background: var(--mint); border-color: #cfe9dc; }
.level-course-group { margin: 0 0 14px; }
.level-course-group summary { align-items: center; background: var(--paper); border: 1px solid var(--line); border-radius: 14px; color: var(--ink); cursor: pointer; display: flex; font-size: 13px; gap: 24px; justify-content: center; list-style: none; padding: 8px 18px; }
.level-course-group summary::-webkit-details-marker { display: none; }
.level-course-group summary::after { align-items: center; color: var(--accent-deep); content: "+"; display: inline-flex; flex: 0 0 44px; font-size: 20px; height: 44px; justify-content: center; line-height: 1; }
.level-course-group[open] summary { border-bottom-left-radius: 0; border-bottom-right-radius: 0; }
.level-course-group[open] summary::after { content: "−"; }
.level-course-group__summary-content { align-items: center; display: inline-flex; gap: 28px; }
.level-course-group__summary-content > span { align-items: center; display: inline-flex; gap: 8px; white-space: nowrap; }
.level-course-group summary strong { color: var(--accent-deep); font-size: 15px; letter-spacing: .06em; }
.level-course-group > .learning-card-grid { border: 1px solid var(--line); border-top: 0; border-radius: 0 0 14px 14px; padding: 16px; }
.learning-card, .vocab-card, .exercise-card, .lesson-finish, .empty-state { background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius); }
.learning-card { display: grid; gap: 18px; min-height: 230px; padding: 22px; }
.learning-card--completed { border-color: #bfe2d0; }
.learning-card--next { border-color: #aeb8ff; box-shadow: 0 8px 24px rgb(82 102 219 / 9%); }
.learning-card--a0 { background: linear-gradient(135deg, #fff, #f1f3ff); }
.learning-card--a1 { background: linear-gradient(135deg, #fff, #edf9f5); }
.learning-card > div:first-child { align-items: center; display: flex; justify-content: space-between; }
.learning-card h2 { font-size: 23px; letter-spacing: -.045em; margin: 0; }
.learning-card h3 { font-size: 23px; letter-spacing: -.045em; margin: 0; }
.learning-card p { color: var(--ink-soft); font-size: 13px; margin: 0; }
.learning-card__footer { align-items: center; border-top: 1px solid var(--line); color: var(--ink-faint); display: flex; font-size: 12px; justify-content: space-between; padding-top: 14px; }
.back-link { color: var(--accent-deep); display: inline-block; font-size: 13px; font-weight: 700; margin-bottom: 26px; }
.lesson-heading { margin-bottom: 37px; max-width: 720px; min-width: 0; width: 100%; }
.lesson-heading h1 { font-size: clamp(35px, 4vw, 52px); letter-spacing: -.06em; min-width: 0; overflow-wrap: anywhere; white-space: normal; }
.reading-section { background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius); margin: 0 0 34px; max-width: 1120px; padding: 24px; }
.reading-section__heading { align-items: flex-start; display: flex; gap: 18px; justify-content: space-between; }
.reading-section__heading .eyebrow { margin-left: 0; }
.reading-section h2 { font-size: 28px; letter-spacing: -.045em; margin: 0; }
.reading-section__status { background: var(--accent-pale); border-radius: 100px; color: var(--accent-deep); font-size: 10px; font-weight: 700; padding: 5px 9px; white-space: nowrap; }
.reading-section__status .zh-hint { color: currentColor; font-size: 9px; }
.reading-layout { display: grid; gap: 18px; grid-template-columns: minmax(0, 1fr) 238px; margin-top: 22px; min-width: 0; }
.reading-main, .reading-section__heading, .reading-sentences, .reading-sentence { min-width: 0; }
.reading-controls { align-items: center; background: #f5f6f8; border-radius: 14px; display: grid; gap: 9px 10px; grid-template-columns: auto auto minmax(80px, 1fr) auto; padding: 16px; }
.reading-controls--segments { grid-template-columns: auto auto; justify-content: start; }
.reading-controls--segments .reading-progress, .reading-controls--segments .reading-time { display: none; }
.reading-control { align-items: center; background: var(--paper); border: 1px solid #dce1ea; border-radius: 10px; color: var(--ink); cursor: pointer; display: inline-flex; font-size: 13px; font-weight: 750; justify-content: center; min-height: 44px; padding: 0 14px; }
.reading-control:hover { border-color: var(--accent); }
.reading-control--primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.reading-control--primary:hover { background: var(--accent-deep); }
.reading-control--reset { font-size: 17px; padding: 0; width: 42px; }
.reading-control .zh-hint { color: currentColor; display: inline; font-size: 10px; margin-left: 5px; }
.reading-progress { background: #e0e4ec; border-radius: 99px; height: 8px; min-width: 0; overflow: hidden; }
.reading-progress span { background: var(--accent); border-radius: inherit; display: block; height: 100%; width: 0; }
.reading-time { color: var(--ink-faint); font-size: 11px; white-space: nowrap; }
.reading-speed { align-items: center; color: var(--ink-faint); display: flex; font-size: 11px; gap: 8px; grid-column: 1 / span 2; }
.reading-speed .zh-hint { display: inline; font-size: 10px; margin-left: 4px; }
.reading-speed select { background: var(--paper); border: 1px solid #dce1ea; border-radius: 9px; color: var(--ink); font: inherit; padding: 8px 10px; }
.reading-controls__hint { color: #c0c7d3; font-size: 11px; grid-column: 3 / -1; margin: 0; text-align: right; }
.reading-controls__hint .zh-hint { display: inline; font-size: 10px; margin-left: 5px; }
.reading-sentences { border: 1px solid var(--line); margin-top: 22px; }
.reading-sentence { border-bottom: 1px solid var(--line); padding: 18px 20px 16px; }
.reading-sentence:last-child { border-bottom: 0; }
.reading-sentence__de { color: var(--ink); font-family: Georgia, "Times New Roman", serif; font-size: clamp(18px, 2vw, 23px); line-height: 1.65; margin: 0; overflow-wrap: anywhere; }
.reading-sentence--heading { background: #f7f8fa; padding-bottom: 10px; padding-top: 10px; }
.reading-section-label { color: var(--ink-faint); display: block; font: 750 11px/1.4 Arial, sans-serif; letter-spacing: .08em; margin-bottom: 5px; text-transform: uppercase; }
.reading-sentence--heading .reading-section-label { color: var(--accent-deep); font-size: 12px; margin: 0; }
.reading-dialogue { align-items: baseline; display: grid; gap: 12px; grid-template-columns: minmax(64px, auto) minmax(0, 1fr); }
.reading-speaker { background: var(--accent-pale); border-radius: 5px; color: var(--accent-deep); font: 750 11px/1.4 Arial, sans-serif; justify-self: start; padding: 4px 7px; }
.reading-schedule { align-items: baseline; display: flex; flex-wrap: wrap; gap: 8px; }
.reading-schedule__dash { color: var(--ink-faint); font-family: Arial, sans-serif; }
.reading-field-label { color: var(--ink-soft); font: 700 13px/1.5 Arial, sans-serif; }
.reading-sentence--field { background: #fbfbfc; padding-bottom: 12px; padding-top: 12px; }
.reading-sentence--labeled .reading-field-label { color: var(--accent-deep); }
.reading-sentence--table { padding-bottom: 16px; padding-top: 16px; }
.reading-table__label-zh { color: var(--ink-soft); display: block; font-size: 14px; line-height: 1.5; margin: -2px 0 12px; }
.reading-table-wrap { max-width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; }
.reading-table-wrap:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.reading-table { border-collapse: collapse; min-width: 100%; width: max-content; }
.reading-table--wide { min-width: 700px; }
.reading-table th, .reading-table td { border: 1px solid var(--line); padding: 12px 14px; text-align: left; vertical-align: top; }
.reading-table th { background: #f7f8fa; color: var(--accent-deep); font: 750 11px/1.45 Arial, sans-serif; letter-spacing: .07em; text-transform: uppercase; }
.reading-table .reading-table__row-heading { background: #fbfbfc; color: var(--ink-soft); font: 700 15px/1.5 Arial, sans-serif; letter-spacing: 0; text-transform: none; }
.reading-table td { color: var(--ink); font: 18px/1.5 Georgia, "Times New Roman", serif; }
.reading-table th > span, .reading-table td > span { display: block; }
.reading-table__zh { color: var(--ink-soft); font: 14px/1.5 Arial, sans-serif; letter-spacing: 0; margin-top: 3px; text-transform: none; }
.reading-word-wrap { display: inline; position: relative; }
.reading-word { background: transparent; border: 0; border-bottom: 1px dotted #8ea2e8; color: inherit; cursor: pointer; font: inherit; line-height: 1.45; min-height: 32px; min-width: 24px; padding: 2px 3px; text-decoration: none; }
.reading-word:hover, .reading-word[aria-expanded="true"] { background: #eef0ff; border-radius: 4px; }
.word-popover { background: var(--paper); border: 1px solid #dbe1ef; border-radius: 12px; box-shadow: 0 12px 30px rgb(29 36 64 / 16%); color: var(--ink); display: grid; gap: 6px; left: 0; min-width: 200px; padding: 12px 14px; position: absolute; text-align: left; top: calc(100% + 10px); width: max-content; z-index: 8; }
.word-popover--above { bottom: calc(100% + 10px); top: auto; }
.word-popover--align-right { left: auto; right: 0; }
.word-popover[hidden] { display: none; }
.word-popover__top { align-items: center; display: flex; gap: 8px; }
.word-popover__top strong { font-family: Georgia, "Times New Roman", serif; font-size: 18px; }
.word-popover__meaning { color: var(--ink-soft); font-size: 13px; }
.word-popover__audio { align-items: center; align-self: start; background: var(--accent-pale); border: 0; border-radius: 9px; color: var(--accent-deep); cursor: pointer; display: inline-flex; font: inherit; font-size: 12px; font-weight: 750; gap: 4px; margin-top: 4px; min-height: 44px; padding: 8px 10px; }
.word-popover__audio:hover { background: #e1e5ff; }
.reading-control:disabled { cursor: wait; opacity: .72; }
.word-popover__plural { color: var(--ink-faint); font-size: 11px; }
.word-popover__example { border-left: 2px solid var(--accent-pale); color: var(--ink-soft); display: block; font-size: 12px; font-style: italic; margin: 2px 0 0; padding-left: 8px; }
.reading-sentence__zh { color: var(--ink-soft); font-size: 14px; line-height: 1.6; margin: 4px 0 0; }
.reading-sentence__zh.is-placeholder { color: var(--ink-faint); font-style: italic; }
.reading-vocab-panel { background: #f7f8fa; border: 1px solid #e0e4eb; border-radius: 14px; padding: 18px; }
.reading-vocab-panel .eyebrow { margin-left: 0; margin-right: 0; }
.reading-vocab-item { display: grid; gap: 1px; margin: 22px 0; }
.reading-vocab-item strong { font-family: Georgia, "Times New Roman", serif; font-size: 19px; }
.reading-vocab-item span { color: var(--ink-soft); font-size: 13px; }
.reading-vocab-empty { color: var(--ink-soft); font-size: 12px; }
.reading-vocab-panel__hint { color: var(--ink-faint); font-size: 12px; line-height: 1.6; margin: 20px 0 0; }
.reading-vocab-button { background: var(--accent); border: 0; border-radius: 10px; color: #fff; cursor: pointer; font-size: 12px; font-weight: 750; margin-top: 12px; min-height: 42px; padding: 0 12px; width: 100%; }
.reading-vocab-button:hover { background: var(--accent-deep); }
.reading-vocab-button--secondary { background: var(--paper); border: 1px solid #dce1ea; color: var(--ink); }
.reading-vocab-button--secondary:hover { background: #eef0ff; }
.reading-vocab-button .zh-hint { color: currentColor; display: inline; font-size: 10px; margin-left: 5px; }
.reading-summary { background: var(--accent-pale); border-radius: 12px; margin-top: 22px; padding: 14px 16px; }
.reading-summary .eyebrow { color: var(--accent-deep); margin: 0 0 6px; }
.reading-summary p:last-child { color: var(--ink-soft); font-size: 13px; line-height: 1.65; margin: 0; }
.reading-section--empty { background: var(--lilac); }
.reading-section--empty h2 { font-size: 23px; }
.reading-section--empty > p:not(.eyebrow) { color: var(--ink-soft); font-size: 13px; margin: 8px 0 0; }
.vocabulary-grid { margin-bottom: 34px; }
.vocab-card { display: grid; gap: 8px; min-height: 205px; padding: 18px; }
.vocab-card__top { align-items: center; display: flex; justify-content: space-between; min-height: 25px; }
.vocab-card h3 { font-size: 25px; letter-spacing: -.045em; margin: 0; overflow-wrap: anywhere; }
.vocab-card p { color: var(--ink-soft); font-size: 13px; margin: 0; }
.vocab-card__plural, .vocab-card__state { color: var(--ink-faint); font-size: 11px; }
.vocab-card__example { border-left: 2px solid var(--accent-pale); font-style: italic; padding-left: 9px; }
.article-badge { border-radius: 100px; font-size: 11px; font-weight: 800; padding: 4px 8px; }
.article-badge--der { background: #e9f0ff; color: #315bb6; }
.article-badge--die { background: #ffedf1; color: #b23e65; }
.article-badge--das { background: #e9f8ee; color: #28764d; }
.text-button { align-self: end; background: transparent; border: 0; color: var(--accent-deep); cursor: pointer; font: inherit; font-size: 12px; font-weight: 700; min-height: 44px; padding: 3px 0; text-align: left; }
.exercise-card { margin: 30px 0; max-width: 760px; padding: 24px; }
.exercise-card h2 { font-size: 22px; letter-spacing: -.035em; margin: 0 0 17px; }
.grammar-section { margin: 38px 0; }
.grammar-grid { display: grid; gap: 14px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grammar-card { background: linear-gradient(145deg, #fff, #f7f5ff); border: 1px solid var(--line); border-radius: 16px; padding: 20px; }
.grammar-card h3 { color: var(--accent-deep); font-size: 17px; margin: 0 0 9px; }
.grammar-card p { color: var(--ink-soft); font-size: 14px; line-height: 1.65; margin: 0; }
.grammar-card blockquote { border-left: 3px solid var(--accent); color: var(--ink); font-size: 15px; font-style: italic; line-height: 1.6; margin: 16px 0 0; padding-left: 13px; }
.answer-options { display: grid; gap: 9px; }
.answer-option { background: #f7f8fc; border: 1px solid var(--line); border-radius: 10px; color: var(--ink); cursor: pointer; font: inherit; min-height: 44px; padding: 12px 14px; text-align: left; }
.answer-option:hover { border-color: var(--accent); background: var(--accent-pale); }
.answer-option:disabled:hover { background: #f7f8fc; border-color: var(--line); }
.answer-row { display: flex; gap: 9px; }
.answer-row input { border: 1px solid var(--line); border-radius: 9px; color: var(--ink); font: inherit; min-width: 0; padding: 10px 12px; width: 100%; }
.exercise-feedback { border-radius: 9px; font-size: 13px; margin: 15px 0 0; padding: 10px 12px; }
.exercise-feedback.is-correct { background: var(--mint); color: #28764d; }
.exercise-feedback.is-wrong { background: #fff0f2; color: #9f3151; }
.lesson-finish { align-items: center; display: flex; justify-content: space-between; margin: 34px 0; max-width: 760px; padding: 19px 22px; }
.lesson-finish p { color: var(--ink-soft); font-size: 13px; margin: 3px 0 0; }
.empty-state { margin: 20px auto; max-width: 680px; padding: 36px; text-align: center; }
.empty-state h1, .empty-state h2 { margin: 0 0 10px; }
.empty-state p { color: var(--ink-soft); margin: 0 0 18px; }
.sr-only { height: 1px; margin: -1px; overflow: hidden; position: absolute; width: 1px; clip: rect(0, 0, 0, 0); }
.backup-section { background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius); margin: 0 0 54px; max-width: 760px; padding: 22px; }
.backup-section h2 { font-size: 22px; letter-spacing: -.035em; margin: 0 0 7px; }
.backup-section > p:not(.eyebrow) { color: var(--ink-soft); font-size: 13px; line-height: 1.6; margin: 0 0 18px; }
.backup-actions { align-items: center; display: flex; flex-wrap: wrap; gap: 10px; }
.backup-actions .button { min-height: 38px; padding: 0 14px; }
.button--secondary { background: var(--accent-pale); color: var(--accent-deep); }
.button--secondary:hover { background: #dfe3ff; }
.backup-actions input[type="file"] { height: 1px; opacity: 0; overflow: hidden; position: absolute; width: 1px; }
.backup-actions input[type="file"]:focus-visible + label { outline: 2px solid var(--accent); outline-offset: 3px; }
.lesson-stepper { margin: 0 0 32px; max-width: 900px; }
.lesson-stepper ol { display: grid; gap: 8px; grid-template-columns: repeat(4, minmax(0, 1fr)); list-style: none; margin: 0; padding: 0; }
.lesson-stepper__item a { align-items: center; border-bottom: 2px solid var(--line); color: var(--ink-faint); display: flex; gap: 8px; min-height: 48px; padding: 8px 4px; }
.lesson-stepper__item.is-current a { border-color: var(--accent); color: var(--accent-deep); font-weight: 750; }
.lesson-stepper__item.is-past a { border-color: #bfe2d0; color: #28764d; }
.lesson-stepper__number { align-items: center; background: #eef0f5; border-radius: 50%; display: inline-flex; flex: 0 0 24px; font-size: 11px; height: 24px; justify-content: center; }
.lesson-stepper__item.is-current .lesson-stepper__number { background: var(--accent); color: #fff; }
.lesson-stepper__item.is-past .lesson-stepper__number { background: var(--mint); color: #28764d; }
.lesson-stepper__progress { color: var(--ink-faint); font-size: 12px; margin: 10px 0 0; }
.lesson-step-actions { align-items: center; display: flex; gap: 10px; justify-content: space-between; margin: 28px 0 42px; max-width: 760px; }
.filter-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 24px; }
.filter-tab { background: var(--paper); border: 1px solid var(--line); border-radius: 999px; color: var(--ink-soft); display: inline-flex; font-size: 12px; font-weight: 700; min-height: 44px; padding: 0 14px; align-items: center; }
.filter-tab:hover, .filter-tab.is-active { background: var(--accent-pale); border-color: #c7ceff; color: var(--accent-deep); }

.home-editorial { margin: 0 auto; max-width: none; }
.home-editorial__masthead { border-bottom: 2px solid var(--line-strong); padding: 8px 0 18px; text-align: center; }
.home-editorial__masthead .eyebrow { margin: 0 0 7px; }
.home-editorial__masthead h1 { font-size: clamp(40px, 5vw, 62px); letter-spacing: -.035em; margin: 0 auto 5px; max-width: none; text-transform: uppercase; }
.home-editorial__masthead h1 .zh-hint { display: none; }
.home-editorial__masthead > p:last-child { color: var(--ink-soft); margin: 0 auto; }
.home-editorial__masthead > p:last-child .zh-hint { display: block; font-size: .78em; margin: 2px 0 0; }
.home-editorial__lead { border-bottom: 1px solid var(--line); display: grid; grid-template-columns: minmax(220px, .9fr) minmax(400px, 1.9fr) minmax(220px, .9fr); min-height: 330px; }
.home-editorial__lead-copy { align-self: center; border-right: 1px solid var(--line); padding: 32px 28px 32px 0; }
.home-editorial__lead-copy h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(30px, 3vw, 48px); letter-spacing: -.045em; line-height: 1.04; margin: 0 0 14px; }
.home-editorial__lead-copy > p:not(.eyebrow) { color: var(--ink-soft); margin: 0 0 20px; }
.home-editorial__lead-copy .button { border-radius: 2px; }
.editorial-media { align-items: end; background: #e9edff; color: var(--accent-deep); display: flex; justify-content: flex-start; min-height: 100%; overflow: hidden; padding: 18px; position: relative; }
.editorial-media::before { background: linear-gradient(180deg, transparent 35%, rgb(17 25 57 / 38%)); content: ""; inset: 0; position: absolute; z-index: 0; }
.editorial-media::after { border: 1px solid rgb(255 255 255 / 36%); content: ""; inset: 12px; position: absolute; z-index: 0; }
.editorial-media span { color: #fff; font-size: clamp(42px, 7vw, 90px); font-weight: 800; letter-spacing: -.08em; line-height: .8; position: relative; text-shadow: 0 2px 14px rgb(0 0 0 / 28%); z-index: 1; }
.editorial-media--lead { min-height: 330px; }
.editorial-media--a0 { background-position: 22% center; }
.editorial-media--a1 { background-position: 50% center; }
.editorial-media--a2 { background-position: 76% center; }
.editorial-media--b1 { background-position: right center; }
.editorial-media--b2 { background-position: 34% center; }
.home-editorial__review { border-left: 1px solid var(--line); display: flex; flex-direction: column; justify-content: center; padding: 30px 0 30px 24px; }
.home-editorial__review .eyebrow { margin: 0 0 14px; }
.home-editorial__review strong { font-size: 44px; letter-spacing: -.06em; line-height: 1; }
.home-editorial__review > p { color: var(--ink-soft); margin: 5px 0 20px; }
.home-editorial__review .text-link { border-top: 1px solid var(--line); display: flex; justify-content: space-between; padding: 12px 0; white-space: normal; }
.home-editorial__featured, .home-editorial__sections { padding: 24px 0; }
.home-editorial__section-heading { align-items: end; display: flex; justify-content: space-between; margin-bottom: 18px; }
.home-editorial__section-heading .eyebrow { margin: 0 0 6px; }
.home-editorial__section-heading h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(24px, 3vw, 34px); letter-spacing: -.04em; margin: 0; }
.home-editorial__stats { color: var(--ink-soft); display: flex; gap: 18px; font-size: 12px; }
.home-editorial__stats span + span { border-left: 1px solid var(--line); padding-left: 18px; }
.editorial-course-grid { border-top: 1px solid var(--line); display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.editorial-course-tile { border-bottom: 1px solid var(--line); border-left: 1px solid var(--line); min-width: 0; }
.editorial-course-tile:first-child { border-left: 0; }
.editorial-course-tile a { display: block; height: 100%; }
.editorial-course-tile a:hover .editorial-course-tile__arrow { transform: translateX(4px); }
.editorial-course-tile .editorial-media { min-height: 128px; }
.editorial-course-tile__copy { display: grid; gap: 5px; padding: 13px 14px 15px 0; position: relative; }
.editorial-course-tile__copy strong { font-family: Georgia, "Times New Roman", serif; font-size: 18px; line-height: 1.1; }
.editorial-course-tile__copy > span:not(.editorial-course-tile__arrow) { color: var(--accent-deep); font-size: 11px; }
.editorial-course-tile__arrow { color: var(--accent-deep); font-size: 22px; position: absolute; right: 12px; top: 18px; transition: transform .2s ease; }
.home-editorial__quick-links { border-bottom: 2px solid var(--line-strong); border-top: 1px solid var(--line); display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.home-editorial__quick-links a { align-items: center; border-left: 1px solid var(--line); display: flex; font-size: 12px; font-weight: 700; justify-content: center; min-height: 72px; padding: 10px 42px; position: relative; text-align: center; }
.home-editorial__quick-links a:first-child { border-left: 0; }
.home-editorial__quick-links a:hover { color: var(--accent-deep); }
.home-editorial__quick-link-label { display: grid; gap: 2px; justify-items: center; }
.home-editorial__quick-link-label strong { font-family: Georgia, "Times New Roman", serif; font-size: 15px; line-height: 1.2; }
.home-editorial__quick-links .zh-hint { display: block; font-size: 10px; margin: 0; }
.home-editorial__quick-link-arrow { font-size: 18px; position: absolute; right: 16px; }
.home-editorial__sections { border-bottom: 0; }
.home-editorial__level-heading { align-items: center; border-top: 3px solid var(--line-strong); flex-direction: column; gap: 16px; padding-top: 22px; text-align: center; }
.home-editorial__level-heading .eyebrow { margin-left: 0; margin-right: 0; }
.home-editorial__level-heading .home-editorial__stats { justify-content: center; }
.home-editorial__sections .level-course-group { border-top: 1px solid var(--line); margin: 0; }
.home-editorial__sections .level-course-group > summary { border-radius: 0; padding-left: 0; padding-right: 0; }
.home-editorial__sections .level-course-group > .learning-card-grid { border: 0; border-radius: 0; padding: 16px 0 24px; }
.home-editorial__sections .learning-card { align-content: start; border-radius: 0; box-shadow: none; grid-template-columns: 120px minmax(0, 1fr); grid-template-rows: auto auto 1fr auto; min-height: 154px; padding: 0; }
.home-editorial__sections .learning-card__media { grid-column: 1; grid-row: 1 / -1; min-height: 100%; }
.home-editorial__sections .learning-card > div:not(.learning-card__media):not(.learning-card__footer) { grid-column: 2; grid-row: 1; padding: 16px 16px 0; }
.home-editorial__sections .learning-card h3 { grid-column: 2; grid-row: 2; margin-left: 16px; margin-right: 16px; }
.home-editorial__sections .learning-card p { grid-column: 2; grid-row: 3; margin-left: 16px; margin-right: 16px; }
.home-editorial__sections .learning-card__footer { grid-column: 2; grid-row: 4; margin-left: 16px; margin-right: 16px; }
.learning-card__media { min-height: 100%; }
.learning-card__media span { font-size: 34px; }

.course-catalog { margin: 0 auto; max-width: 1600px; }
.course-catalog__heading { border-bottom: 2px solid var(--ink); padding: 30px 0 26px; }
.course-catalog__heading h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(48px, 5vw, 72px); letter-spacing: -.045em; line-height: 1; max-width: none; }
.course-catalog__heading h1 span { color: var(--ink-soft); font-family: Arial, "Microsoft YaHei", sans-serif; font-size: .35em; font-weight: 400; letter-spacing: 0; margin-left: 20px; }
.course-catalog__filters { border-bottom: 1px solid var(--line); display: flex; overflow-x: auto; scrollbar-width: thin; }
.course-catalog__filters a { color: var(--ink-soft); flex: 0 0 auto; font-size: 17px; font-weight: 700; min-width: 88px; padding: 18px 27px; position: relative; text-align: center; }
.course-catalog__filters a:first-child { min-width: 100px; }
.course-catalog__filters a:hover, .course-catalog__filters a[aria-current] { color: var(--ink); }
.course-catalog__filters a[aria-current]::after { background: var(--accent); bottom: 0; content: ""; height: 4px; left: 23px; position: absolute; right: 23px; }
.course-catalog__level { border-bottom: 2px solid var(--ink); display: grid; gap: 44px; grid-template-columns: 310px minmax(0, 1fr); padding: 32px 0 41px; }
.course-catalog__side { display: flex; flex-direction: column; min-width: 0; }
.course-catalog__code { display: block; font-family: Georgia, "Times New Roman", serif; font-size: 83px; font-weight: 700; letter-spacing: -.055em; line-height: .92; }
.course-catalog__side h2 { font-family: Georgia, "Times New Roman", serif; font-size: 31px; letter-spacing: -.025em; line-height: 1.1; margin: 16px 0 4px; }
.course-catalog__side p { color: var(--ink-soft); font-size: 18px; margin: 0 0 22px; }
.course-catalog__side picture { display: block; flex: 1 1 0; min-height: 0; overflow: hidden; }
.course-catalog__side img { display: block; height: 100%; object-fit: cover; width: 100%; }
.course-catalog__count { color: var(--ink-soft); display: block; font-size: 15px; margin-top: 12px; }
.course-catalog__list { border-top: 1px solid var(--line); min-width: 0; }
.course-catalog__row { align-items: center; border-bottom: 1px solid var(--line); display: grid; gap: 19px; grid-template-columns: 49px minmax(0, 1fr) 160px 25px; min-height: 94px; padding: 12px 9px 12px 5px; }
.course-catalog__row:last-child { border-bottom: 0; }
.course-catalog__row:hover { background: #f7f8fd; }
.course-catalog__number { color: var(--ink-soft); font-family: Georgia, "Times New Roman", serif; font-size: 25px; }
.course-catalog__name { min-width: 0; }
.course-catalog__name strong { display: block; font-family: Georgia, "Times New Roman", serif; font-size: 27px; line-height: 1.08; }
.course-catalog__name span { color: var(--ink-soft); display: block; font-size: 16px; margin-top: 6px; }
.course-catalog__meta { color: var(--ink-soft); font-size: 15px; line-height: 1.5; text-align: right; }
.course-catalog__meta strong { color: var(--accent); display: block; }
.course-catalog__meta .zh-hint { display: inline; font-size: .85em; margin-left: 4px; }
.course-catalog__arrow { color: var(--accent); font-size: 26px; }
.course-catalog__empty { color: var(--ink-soft); padding: 30px 5px; }

/* Editorial reading and study surfaces: preserve the existing lesson flow, change only the visual language. */
.lesson-heading { border-bottom: 2px solid var(--line-strong); margin-bottom: 24px; max-width: none; padding-bottom: 22px; }
.lesson-heading h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(38px, 5vw, 62px); letter-spacing: -.045em; max-width: 900px; }
.lesson-heading > p:not(.eyebrow) { color: var(--ink-soft); font-size: 16px; }
.lesson-stepper { margin-bottom: 26px; max-width: none; }
.lesson-stepper ol { gap: 0; }
.lesson-stepper__item a { border-bottom-width: 3px; padding: 8px 12px 11px 0; }
.reading-section { border: 0; border-top: 3px solid var(--line-strong); border-radius: 0; max-width: none; padding: 22px 0 0; }
.reading-section__heading { border-bottom: 1px solid var(--line); padding-bottom: 16px; }
.reading-section h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(26px, 3vw, 38px); }
.reading-controls { border: 1px solid var(--line); border-radius: 0; }
.reading-sentences { border: 0; border-top: 1px solid var(--line); }
.reading-sentence { padding-left: 0; padding-right: 0; }
.reading-vocab-panel { background: var(--paper); border: 0; border-left: 1px solid var(--line); border-radius: 0; padding: 0 0 0 22px; }
.reading-vocab-item { border-bottom: 1px solid var(--line); margin: 0; padding: 16px 0; }
.reading-summary { border-radius: 0; border-top: 1px solid var(--line); }
.vocab-card, .exercise-card, .grammar-card, .empty-state { border-radius: 0; box-shadow: none; }
.vocab-card { border-top: 3px solid var(--line-strong); }
.filter-tabs { border-bottom: 1px solid var(--line); padding-bottom: 12px; }
.filter-tab { border-radius: 0; }

@media (max-width: 900px) {
  :root { --sidebar-width: 224px; }
  .page-wrap { padding-top: 46px; }
  .topbar__context { grid-template-columns: 1fr; }
  .breadcrumbs { display: none; }
  .home-editorial__lead { grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); }
  .home-editorial__review { border-left: 0; border-top: 1px solid var(--line); grid-column: 1 / -1; padding-left: 0; }
  .editorial-course-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .editorial-course-tile:nth-child(odd) { border-left: 0; }
}

@media (max-width: 700px) {
  .sidebar { box-shadow: 10px 0 34px rgb(25 35 76 / 10%); transform: translateX(-105%); transition: transform .25s ease, visibility 0s linear .25s; visibility: hidden; }
  .sidebar.is-open { transform: translateX(0); transition-delay: 0s; visibility: visible; }
  .sidebar__top { margin-bottom: 40px; }
  .sidebar__collapse { display: none; }
  .sidebar__close { display: inline-flex; }
  .sidebar-scrim { background: rgb(22 28 52 / 30%); inset: 0 auto 0 0; opacity: 0; pointer-events: none; position: fixed; transition: opacity .2s ease; width: 100vw; max-width: 100%; z-index: 15; }
  .sidebar-scrim.is-visible { opacity: 1; pointer-events: auto; }
  .main-content { margin-left: 0; }
  .topbar { padding: 0 18px; }
  .topbar__utility { height: 60px; }
  .topbar__brand { gap: 6px; }
  .topbar__brand-word { gap: 1px; }
  .topbar__brand-tile { font-size: 11px; height: 21px; width: 18px; }
  .topbar__nav { display: none; }
  .topbar__context { display: block; min-height: 34px; }
  .topbar__level-nav { display: none; }
  .menu-toggle { display: inline-flex; }
  .menu-toggle__bars { display: grid; gap: 4px; }
  .menu-toggle__bars i { background: currentColor; border-radius: 2px; display: block; height: 1.5px; width: 17px; }
  .breadcrumbs { margin-right: auto; margin-left: 14px; }
  .topbar__actions { gap: 0; }
  .topbar__language, .topbar__locale { display: none; }
  .streak { display: none; }
  .page-wrap { padding: 38px 18px 26px; }
  h1 { font-size: clamp(37px, 11vw, 53px); }
  .lesson-heading { max-width: calc(100vw - 36px); }
  .lesson-heading h1 { font-size: clamp(24px, 7.5vw, 34px); max-width: calc(100vw - 36px); overflow-wrap: anywhere; width: calc(100vw - 36px); }
  .lesson-heading h1 + p { font-size: 13px; max-width: calc(100vw - 36px); overflow-wrap: anywhere; white-space: normal; width: calc(100vw - 36px); }
  .learning-summary, .learning-card-grid, .vocabulary-grid, .grammar-grid { grid-template-columns: 1fr; }
  .learning-summary > div + div { border-left: 0; border-top: 1px solid var(--line); }
  .learning-summary > div { padding: 15px 17px; }
  .lesson-finish { align-items: flex-start; flex-direction: column; gap: 14px; }
  .answer-row { flex-direction: column; }
  .reading-section { padding: 18px; }
  .reading-section { max-width: calc(100vw - 36px); width: calc(100vw - 36px); }
  .reading-section__heading { display: grid; gap: 10px; }
  .reading-section h2 { font-size: 24px; }
  .reading-section__status { justify-self: start; }
  .reading-layout { grid-template-columns: 1fr; }
  .reading-vocab-panel { border-left: 0; border-top: 1px solid var(--line); padding: 18px 0 0; }
  .reading-controls { grid-template-columns: auto auto minmax(0, 1fr); }
  .reading-time { grid-column: 1 / -1; }
  .reading-speed { grid-column: 1 / -1; }
  .reading-controls__hint { grid-column: 1 / -1; text-align: left; }
  .reading-sentence { padding: 16px; }
  .reading-sentence__de { font-size: 16px; }
  .reading-table { min-width: 480px; }
  .reading-table--wide { min-width: 700px; }
  .reading-table th, .reading-table td { padding: 10px; }
  .reading-table td { font-size: 15px; }
  .reading-table .reading-table__row-heading { font-size: 13px; }
  .reading-table__zh { font-size: 12px; }
  .word-popover { max-width: calc(100vw - 48px); min-width: 180px; white-space: normal; }
  .continue-card { align-items: flex-start; flex-direction: column; gap: 14px; }
  .continue-card .button { width: 100%; }
  .level-course-group > .learning-card-grid { padding: 12px; }
  .lesson-stepper ol { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .lesson-stepper__item a { min-height: 44px; }
  .lesson-step-actions { align-items: stretch; flex-direction: column; }
  .lesson-step-actions .button { width: 100%; }
  .learning-section { margin-bottom: 44px; }
  .section-heading { align-items: flex-start; gap: 10px; }
  .section-heading h2 { font-size: 22px; }
  .home-editorial__lead { grid-template-columns: 1fr; }
  .home-editorial__lead-copy { padding-right: 0; }
  .home-editorial__lead-media { min-height: 220px; }
  .home-editorial__hero-image { min-height: 260px; }
  .home-editorial__review { grid-column: auto; padding-left: 0; }
  .editorial-course-grid { grid-template-columns: 1fr; }
  .editorial-course-tile, .editorial-course-tile:nth-child(odd) { border-left: 0; }
  .home-editorial__quick-links { grid-template-columns: 1fr; }
  .home-editorial__quick-links a, .home-editorial__quick-links a:first-child { border-left: 0; border-top: 1px solid var(--line); }
  .home-editorial__quick-links a:first-child { border-top: 0; }
  .home-editorial__section-heading { align-items: flex-start; gap: 12px; }
  .home-editorial__level-heading { align-items: center; text-align: center; }
  .home-editorial__stats { flex-direction: column; gap: 4px; }
  .home-editorial__level-heading .home-editorial__stats { align-items: center; }
  .home-editorial__stats span + span { border-left: 0; padding-left: 0; }
  .home-editorial__sections .level-course-group > summary { gap: 10px; }
  .home-editorial__sections .level-course-group__summary-content { gap: 16px; }
  .home-editorial__masthead h1 { font-size: clamp(32px, 10vw, 48px); }
  .home-editorial__sections .learning-card { grid-template-columns: 92px minmax(0, 1fr); }
  .home-editorial__sections .learning-card h3 { font-size: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}

/* Overview and Courses share the approved HMS editorial shell. */
.brand-name--overview, .topbar__brand--overview { display: none; }
body.is-overview {
  --ink: #1c2549;
  --ink-soft: #657393;
  --line: #dfe4ee;
  --accent: #4162df;
  --accent-deep: #4162df;
  --canvas: #fff;
  font-family: Arial, "Microsoft YaHei", sans-serif;
}
body.is-overview .sidebar .brand-mark,
body.is-overview .sidebar .brand-name:not(.brand-name--overview),
body.is-overview .topbar__brand:not(.topbar__brand--overview),
body.is-overview .topbar__actions,
body.is-overview .topbar__context { display: none; }
body.is-overview .sidebar .brand-name--overview { display: inline; }
body.is-overview .topbar { padding: 0 34px; }
body.is-overview .topbar__utility { height: 105px; max-width: 1600px; }
body.is-overview .topbar__brand--overview { display: inline-flex; gap: 5px; }
body.is-overview .topbar__brand--overview .topbar__brand-tile { background: #101b42; font-size: 34px; height: 53px; width: 53px; }
body.is-overview .topbar__nav { border: 0; gap: 42px; max-width: 1600px; min-height: 63px; }
body.is-overview .topbar__nav-link { color: var(--ink); font-size: 16px; font-weight: 600; padding: 0 0 1px; }
body.is-overview .topbar__nav-link .zh-hint { display: none; }
body.is-overview .topbar__nav-link::after { bottom: auto; height: 2px; top: 18px; }
body.is-overview .page-wrap { max-width: 1600px; min-height: calc(100dvh - 168px); padding: 20px 34px 52px; }

.overview-hero { border: 1px solid var(--line); display: grid; grid-template-columns: 53% 30% 17%; min-height: clamp(360px, 28.4vw, 454px); }
.overview-hero__art { background: #e9e2d4; min-width: 0; overflow: hidden; position: relative; }
.overview-hero__art img { display: block; height: 100%; inset: 0; object-fit: cover; position: absolute; width: 100%; }
.overview-hero__course { align-self: center; min-width: 0; padding: 30px 28px 30px 34px; }
.overview-hero__course h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(38px, 3.6vw, 56px); letter-spacing: -.035em; line-height: .98; margin: 0 0 12px; max-width: 370px; overflow-wrap: normal; }
.overview-hero__zh { font-family: Georgia, "Microsoft YaHei", serif; font-size: clamp(28px, 2.2vw, 38px); line-height: 1.25; margin: 0 0 18px; }
.overview-hero__level { font-size: 18px; font-weight: 700; margin: 0 0 22px; }
.overview-hero__button { align-items: center; background: var(--accent); border-radius: 2px; color: #fff; display: inline-flex; font-size: 16px; font-weight: 700; gap: 8px; min-height: 48px; padding: 12px 22px; white-space: nowrap; }
.overview-hero__button:hover { background: var(--accent-deep); }
.overview-review { align-items: flex-start; border-left: 1px solid var(--line); display: flex; flex-direction: column; justify-content: center; min-width: 0; padding: 28px 24px; }
.overview-review h2 { font-family: Georgia, "Times New Roman", serif; font-size: 41px; letter-spacing: -.02em; margin: 0 0 13px; }
.overview-review strong { color: var(--accent); font-family: Georgia, "Times New Roman", serif; font-size: 76px; line-height: .95; }
.overview-review__due { font-family: Georgia, "Times New Roman", serif; font-size: 24px; font-weight: 700; line-height: 1.04; margin: 9px 0 0; }
.overview-review__breakdown { color: var(--ink-soft); font-size: 16px; margin: 10px 0 27px; }
.overview-review a { align-items: center; border: 1px solid var(--accent); color: var(--accent); display: inline-flex; font-size: 16px; font-weight: 700; gap: 8px; padding: 12px 15px; white-space: nowrap; }
.overview-review a:hover { background: var(--accent); color: #fff; }

.overview-levels { border-top: 1px solid var(--line); display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); margin-top: 24px; padding-top: 18px; }
.overview-level-card { border-right: 1px solid var(--line); display: flex; flex-direction: column; min-width: 0; padding: 0 19px 4px; }
.overview-level-card:first-child { padding-left: 14px; }
.overview-level-card:last-child { border-right: 0; padding-right: 7px; }
.overview-level-card__code { font-family: Georgia, "Times New Roman", serif; font-size: 38px; font-weight: 700; line-height: 1; margin-bottom: 5px; }
.overview-level-card img { aspect-ratio: 1.82; display: block; margin: 0 0 12px; object-fit: cover; width: 100%; }
.overview-level-card strong { font-family: Georgia, "Times New Roman", serif; font-size: 19px; line-height: 1.12; margin-bottom: 4px; }
.overview-level-card > span[lang] { color: var(--ink-soft); font-size: 15px; }
.overview-level-card__arrow { align-self: flex-end; font-size: 23px; margin-top: auto; padding-top: 18px; }
.overview-level-card:hover { color: var(--accent-deep); }
.overview-data-tools { border-top: 1px solid var(--line); color: var(--ink-soft); margin-top: 22px; padding-top: 12px; }
.overview-data-tools > summary { cursor: pointer; font-size: 14px; font-weight: 700; min-height: 44px; padding: 10px 0; }
.overview-data-tools .backup-section { color: var(--ink); margin-top: 16px; }

@media (max-width: 1150px) {
  .overview-hero { grid-template-columns: 48% 52%; }
  .overview-review { border-left: 0; border-top: 1px solid var(--line); flex-direction: row; grid-column: 1 / -1; gap: 12px; justify-content: flex-start; padding: 18px 24px; }
  .overview-review h2 { font-size: 30px; margin: 0 10px 0 0; }
  .overview-review strong { font-size: 48px; }
  .overview-review__due, .overview-review__breakdown { align-self: center; font-size: 17px; margin: 0; }
  .overview-review a { align-self: center; margin-left: auto; }
  .overview-levels { grid-template-columns: repeat(3, minmax(0, 1fr)); row-gap: 22px; }
  .overview-level-card:nth-child(3) { border-right: 0; }
}

@media (max-width: 700px) {
  body.is-overview .topbar { padding: 0 16px; }
  body.is-overview .topbar__utility { height: 80px; }
  body.is-overview .topbar__brand--overview .topbar__brand-tile { font-size: 23px; height: 36px; width: 36px; }
  body.is-overview .topbar__nav { display: none; }
  body.is-overview .page-wrap { padding: 16px 16px 36px; }
  .overview-hero { grid-template-columns: 1fr; }
  .overview-hero__art { height: 240px; }
  .overview-hero__course { padding: 24px; }
  .overview-hero__course h1 { font-size: clamp(38px, 10vw, 52px); }
  .overview-review { align-items: flex-start; flex-direction: column; gap: 0; grid-column: 1; padding: 24px; }
  .overview-review h2 { font-size: 34px; margin-bottom: 10px; }
  .overview-review strong { font-size: 64px; }
  .overview-review__due { align-self: flex-start; font-size: 21px; margin: 7px 0; }
  .overview-review__breakdown { align-self: flex-start; font-size: 15px; margin-bottom: 18px; }
  .overview-review a { align-self: flex-start; margin: 0; }
  .overview-levels { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .overview-level-card, .overview-level-card:first-child, .overview-level-card:last-child { border-right: 1px solid var(--line); padding: 0 10px 10px; }
  .overview-level-card:nth-child(even) { border-right: 0; }
  .overview-level-card__code { font-size: 32px; }
  .overview-level-card strong { font-size: 17px; }
  .overview-level-card > span[lang] { font-size: 13px; }
}

@media (max-width: 900px) {
  .course-catalog__level { gap: 26px; grid-template-columns: 230px minmax(0, 1fr); }
  .course-catalog__code { font-size: 68px; }
  .course-catalog__row { gap: 12px; grid-template-columns: 38px minmax(0, 1fr) 105px 20px; }
  .course-catalog__name strong { font-size: 22px; }
  .course-catalog__meta { font-size: 13px; }
}

@media (max-width: 650px) {
  .course-catalog__heading { padding: 24px 0 18px; }
  .course-catalog__heading h1 { font-size: 48px; }
  .course-catalog__heading h1 span { font-size: 20px; margin-left: 12px; }
  .course-catalog__filters a, .course-catalog__filters a:first-child { flex: 1 0 auto; font-size: 15px; min-width: 0; padding: 15px 8px; white-space: nowrap; }
  .course-catalog__level { display: block; padding: 25px 0 31px; }
  .course-catalog__side { align-items: center; display: grid; gap: 0 14px; grid-template-columns: 91px minmax(0, 1fr); margin-bottom: 23px; }
  .course-catalog__code { font-size: 62px; grid-column: 1; grid-row: 1 / 3; }
  .course-catalog__side h2 { font-size: 27px; grid-column: 2; margin: 0; }
  .course-catalog__side p { font-size: 15px; grid-column: 2; margin: 0; }
  .course-catalog__side picture { grid-column: 1 / -1; height: auto; margin-top: 18px; }
  .course-catalog__side img { aspect-ratio: 2.3; height: auto; }
  .course-catalog__count { display: none; }
  .course-catalog__row { gap: 4px 10px; grid-template-columns: 31px minmax(0, 1fr) 18px; min-height: 88px; }
  .course-catalog__number { font-size: 19px; grid-column: 1; grid-row: 1 / 3; }
  .course-catalog__name { grid-column: 2; grid-row: 1; }
  .course-catalog__name strong { font-size: 19px; }
  .course-catalog__name span { font-size: 13px; margin-top: 3px; }
  .course-catalog__meta { font-size: 12px; grid-column: 2; grid-row: 2; text-align: left; }
  .course-catalog__meta strong { display: inline; margin-right: 5px; }
  .course-catalog__arrow { font-size: 20px; grid-column: 3; grid-row: 1 / 3; }
}

/* Standalone vocabulary index. */
.vocabulary-page { margin: 18px auto 50px; max-width: 1240px; }
.vocabulary-page__heading { align-items: center; display: flex; gap: 24px; justify-content: space-between; margin-bottom: 26px; }
.vocabulary-page__heading h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(48px, 5vw, 72px); letter-spacing: -.045em; line-height: 1; margin: 0; }
.vocabulary-page__search { align-items: center; border: 1px solid var(--line); display: flex; gap: 10px; height: 50px; max-width: 390px; padding: 0 15px; width: 100%; }
.vocabulary-page__search:focus-within { border-color: var(--accent); outline: 2px solid var(--accent-pale); }
.vocabulary-page__search svg { color: var(--ink-soft); flex: none; height: 19px; width: 19px; }
.vocabulary-page__search input { background: transparent; border: 0; color: var(--ink); font: inherit; min-width: 0; outline: 0; width: 100%; }
.vocabulary-page__search input::placeholder { color: var(--ink-soft); opacity: 1; }
.vocabulary-page__levels { border-bottom: 1px solid var(--line); border-top: 2px solid var(--ink); display: flex; overflow-x: auto; }
.vocabulary-page__levels a { align-items: center; border-bottom: 4px solid transparent; color: var(--ink-soft); display: flex; flex: 1 0 auto; gap: 13px; justify-content: center; min-height: 70px; padding: 17px 15px 13px; white-space: nowrap; }
.vocabulary-page__levels a:hover, .vocabulary-page__levels a[aria-current="page"] { color: var(--ink); }
.vocabulary-page__levels a[aria-current="page"] { border-bottom-color: var(--accent); font-weight: 700; }
.vocabulary-page__levels span { font-size: 14px; font-weight: 400; }
.vocabulary-page__list-heading { align-items: end; display: flex; gap: 20px; justify-content: space-between; min-height: 82px; }
.vocabulary-page__list-heading p { color: var(--ink-soft); font-size: 17px; margin: 0 0 17px; }
.vocabulary-page__statuses { display: flex; gap: 25px; }
.vocabulary-page__statuses a { border-bottom: 3px solid transparent; color: var(--ink-soft); padding: 0 0 15px; white-space: nowrap; }
.vocabulary-page__statuses a:hover, .vocabulary-page__statuses a[aria-current="page"] { color: var(--ink); }
.vocabulary-page__statuses a[aria-current="page"] { border-bottom-color: var(--ink); font-weight: 700; }
.vocabulary-page__grid { border-top: 2px solid var(--ink); display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.vocabulary-item { border-bottom: 1px solid var(--line); border-left: 1px solid var(--line); min-width: 0; }
.vocabulary-item:nth-child(4n+1) { border-left: 0; }
.vocabulary-item.is-marked { background: #f7f9ff; }
.vocabulary-item.is-open { box-shadow: inset 0 0 0 1px #bfcae8; }
.vocabulary-item__preview { align-items: flex-start; background: transparent; border: 0; color: inherit; cursor: pointer; display: flex; flex-direction: column; min-height: 160px; padding: 18px 20px; text-align: left; width: 100%; }
.vocabulary-item__preview:hover { background: #f8faff; }
.vocabulary-item__preview:focus-visible, .vocabulary-item__audio:focus-visible, .vocabulary-item__mark:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.vocabulary-item.is-open .vocabulary-item__preview { min-height: 0; padding-bottom: 0; }
.vocabulary-item__word { align-items: baseline; display: flex; flex-wrap: wrap; gap: 8px; max-width: 100%; }
.vocabulary-item__word strong { font-family: Georgia, "Times New Roman", serif; font-size: clamp(24px, 2.2vw, 32px); letter-spacing: -.025em; line-height: 1.12; overflow-wrap: anywhere; }
.vocabulary-item__word em { color: var(--ink-soft); font-size: 13px; font-style: normal; }
.vocabulary-item__ipa { color: var(--accent); font-size: 15px; line-height: 1.3; margin-top: 7px; overflow-wrap: anywhere; }
.vocabulary-item__meaning { font-size: 17px; line-height: 1.35; margin-top: 10px; }
.vocabulary-item__status { align-self: flex-end; color: var(--accent-deep); font-size: 12px; font-weight: 700; line-height: 1.3; margin-top: 11px; }
.vocabulary-item__detail { padding: 13px 20px 18px; }
.vocabulary-item__example { font-family: Georgia, "Times New Roman", serif; font-size: 18px; line-height: 1.35; margin: 0 0 5px; }
.vocabulary-item__translation { color: var(--ink-soft); font-size: 13px; margin: 0 0 14px; }
.vocabulary-item__actions { align-items: center; display: flex; gap: 12px; justify-content: space-between; }
.vocabulary-item__audio { align-items: center; background: #eef2ff; border: 0; color: var(--accent); cursor: pointer; display: inline-flex; flex: none; height: 34px; justify-content: center; width: 34px; }
.vocabulary-item__audio svg { height: 19px; width: 19px; }
.vocabulary-item__mark { background: #fff; border: 1px solid var(--accent); color: var(--accent); cursor: pointer; font-size: 13px; font-weight: 700; min-height: 34px; padding: 5px 8px; white-space: nowrap; }
.vocabulary-item__mark:not(:disabled):hover { background: var(--accent-pale); }
.vocabulary-item[hidden], .vocabulary-item__detail[hidden], .vocabulary-page__empty[hidden] { display: none; }
.vocabulary-page__empty { color: var(--ink-soft); margin: 24px 0; }
/* Lesson reader: compact editorial layout, scoped away from the catalog. */
body.is-overview.is-lesson .topbar__utility { height: 76px; }
body.is-overview.is-lesson .topbar__brand--overview .topbar__brand-tile { font-size: 25px; height: 38px; width: 38px; }
body.is-overview.is-lesson .topbar__nav { min-height: 50px; }
.lesson-page { margin: 0 auto; max-width: 1240px; }
.lesson-page__topline { align-items: center; color: var(--ink-soft); display: flex; font-size: 13px; justify-content: space-between; margin-bottom: 15px; }
.lesson-page .back-link { margin: 0; min-height: 32px; padding: 6px 0; }
.lesson-page .lesson-heading { align-items: start; border: 0; display: flex; gap: 24px; justify-content: space-between; margin: 0 0 19px; max-width: none; padding: 0; }
.lesson-page .lesson-heading h1 { font-size: clamp(32px, 3.5vw, 46px); letter-spacing: -.035em; line-height: 1.12; margin: 0; }
.lesson-page .lesson-heading h1:focus { outline: none; }
.lesson-page .lesson-page__number { color: var(--ink); font-size: 16px; font-variant-numeric: tabular-nums; font-weight: 650; line-height: 1.5; margin: 0 0 6px; }
.lesson-page .lesson-page__subtitle { color: var(--ink-soft); font-size: 17px; line-height: 1.5; margin: 7px 0 0; }
.lesson-goals { flex: 0 0 auto; font-size: 14px; max-width: 340px; padding-top: 10px; }
.lesson-goals summary { color: var(--ink-soft); cursor: pointer; min-height: 32px; padding: 6px 0; text-align: right; }
.lesson-goals ul { background: #f7f9ff; border: 1px solid var(--line); line-height: 1.65; margin: 8px 0 0; padding: 12px 16px 12px 30px; }
.lesson-page .lesson-stepper { margin: 0 0 24px; }
.lesson-page .lesson-stepper ol { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.lesson-page .lesson-stepper__item a { border-bottom: 1px solid var(--line); color: var(--ink-soft); font-size: 15px; justify-content: center; min-height: 44px; padding: 10px 5px; }
.lesson-page .lesson-stepper__item.is-current a { border-bottom: 2px solid var(--accent); color: var(--accent-deep); }
.lesson-page .reading-section { border: 0; max-width: none; padding: 0; width: auto; }
.lesson-page .reading-layout { gap: 30px; grid-template-columns: minmax(0, 1fr) 265px; margin: 0; }
.lesson-page .reading-main { min-width: 0; }
.lesson-page .reading-section__heading { border: 0; display: block; margin-bottom: 15px; padding: 0; }
.lesson-page .reading-section h2 { font-size: clamp(23px, 2.4vw, 29px); letter-spacing: -.025em; line-height: 1.2; margin: 0; }
.lesson-page .reading-controls { align-items: center; background: #f7f8fc; border: 1px solid var(--line); display: flex; flex-wrap: wrap; gap: 10px; padding: 8px 10px; }
.lesson-page .reading-control { border-radius: 3px; font-size: 13px; min-height: 36px; padding: 6px 13px; }
.lesson-page .reading-control--reset { padding: 0; width: 36px; }
.lesson-page .reading-progress { flex: 1 1 75px; height: 4px; }
.lesson-page .reading-time { font-size: 12px; font-variant-numeric: tabular-nums; }
.lesson-page .reading-speed { font-size: 13px; margin-left: auto; }
.lesson-page .reading-speed select { border-radius: 3px; min-height: 36px; padding: 5px 6px; }
.reading-translations { align-items: center; cursor: pointer; display: flex; font-size: 13px; gap: 6px; min-height: 36px; padding: 0 2px; }
.reading-translations input { accent-color: var(--accent); cursor: pointer; height: 16px; width: 16px; }
.lesson-page .reading-sentences { border: 0; margin-top: 15px; }
.lesson-page .reading-sentence { background: transparent; border: 0; padding: 7px 0; }
.lesson-page .reading-sentence__de { font-size: 23px; line-height: 1.55; }
.lesson-page .reading-word { line-height: inherit; min-height: 0; min-width: 0; padding: 0; }
.lesson-page .reading-dialogue { gap: 14px; grid-template-columns: 74px minmax(0, 1fr); }
.lesson-page .reading-speaker { background: transparent; color: var(--ink-soft); font: 600 13px/1.45 Arial, sans-serif; overflow-wrap: anywhere; padding: 0; }
.lesson-page .reading-sentence__zh { font-size: 14px; line-height: 1.5; margin-top: 3px; }
.lesson-page .reading-sentence--dialogue > .reading-sentence__zh { margin-left: 88px; }
.lesson-page .reading-section-label { color: var(--ink); font: 700 14px/1.5 Arial, sans-serif; letter-spacing: 0; margin: 6px 0 9px; }
.lesson-page .reading-sentence--dialogue > .reading-section-label { border-top: 1px solid var(--line); padding-top: 13px; text-transform: lowercase; }
.lesson-page .reading-sentence--dialogue > .reading-section-label::first-letter { text-transform: uppercase; }
.lesson-page .reading-sentence:first-child > .reading-section-label { border-top: 0; margin-top: 0; padding-top: 0; }
.lesson-page .reading-sentence--table { padding: 12px 0; }
.lesson-page .reading-vocab-panel { border: 0; border-left: 1px solid var(--line); padding: 0 0 0 26px; }
.lesson-page .reading-vocab-panel h3 { font-family: Georgia, "Times New Roman", serif; font-size: 23px; margin: 0 0 10px; }
.lesson-page .reading-vocab-item { border: 0; gap: 3px; padding: 10px 0; }
.reading-vocab-item__top { align-items: center; display: flex; gap: 6px; justify-content: space-between; min-width: 0; }
.reading-vocab-item__top > div { min-width: 0; }
.lesson-page .reading-vocab-item strong { font-size: 23px; line-height: 1.2; overflow-wrap: anywhere; }
.reading-vocab-item em { color: var(--ink-soft); font-size: 12px; font-style: normal; }
.lesson-page .reading-vocab-item__ipa { color: var(--accent); font-size: 14px; overflow-wrap: anywhere; }
.lesson-page .reading-vocab-item__meaning { color: var(--ink); font-size: 15px; }
.reading-vocab-item__audio { align-items: center; background: transparent; border: 0; color: var(--accent); cursor: pointer; display: inline-flex; flex: none; height: 34px; justify-content: center; padding: 6px; width: 34px; }
.reading-vocab-item__audio:hover { background: var(--accent-pale); }
.reading-vocab-item__audio svg { height: 19px; width: 19px; }
.reading-section.is-translation-hidden .reading-sentence__zh,
.reading-section.is-translation-hidden .reading-table__zh,
.reading-section.is-translation-hidden .reading-table__label-zh { display: none; }
.lesson-page .lesson-step-actions { border-top: 1px solid var(--line); flex-direction: row; margin: 20px 0 0; max-width: none; padding-top: 16px; }
.lesson-page .lesson-step-actions .button { border-radius: 3px; font-size: 14px; min-height: 44px; padding: 10px 22px; width: auto; }
.lesson-page .lesson-step-actions__next { margin-left: auto; }
.lesson-page .exercise-card { background: transparent; border: 0; border-radius: 0; max-width: none; padding: 20px 0; }
.lesson-page .exercise-card h2 { font-family: Georgia, "Times New Roman", serif; font-size: 26px; }
.lesson-page .answer-option { border-radius: 3px; }
.lesson-heading__meta { flex: 0 0 auto; text-align: right; }
.lesson-page .lesson-heading__meta .lesson-page__number { color: var(--ink); font-family: Georgia, "Times New Roman", serif; font-size: 19px; font-weight: 400; margin: 0; }
.lesson-heading__meta .lesson-goals { padding-top: 4px; }
.lesson-section-heading { align-items: baseline; display: flex; gap: 20px; justify-content: space-between; margin-bottom: 20px; }
.lesson-section-heading h2, .lesson-page .grammar-section > h2, .lesson-page .lesson-finish h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(28px, 3vw, 38px); letter-spacing: -.025em; line-height: 1.2; margin: 0; }
.lesson-section-heading > span { color: var(--ink-soft); font-size: 15px; }
.lesson-vocabulary__grid { align-items: start; border: 0; gap: 12px; }
.lesson-vocabulary__grid .vocabulary-item { border: 1px solid var(--line); }
.lesson-vocabulary__grid .vocabulary-item.is-open { background: #f3f7ff; border-color: var(--accent); box-shadow: none; }
.lesson-vocabulary__grid .vocabulary-item__preview { min-height: 156px; padding: 20px; position: relative; }
.lesson-vocabulary__grid .vocabulary-item__word { padding-right: 16px; }
.lesson-vocabulary__grid .vocabulary-item__word strong { font-size: 29px; }
.lesson-vocabulary__grid .vocabulary-item.is-open .vocabulary-item__preview { min-height: 0; padding-bottom: 0; }
.vocabulary-item__chevron { color: var(--accent-deep); height: 17px; position: absolute; right: 14px; top: 23px; width: 17px; }
.vocabulary-item.is-open .vocabulary-item__chevron { transform: rotate(180deg); }
.vocabulary-item__collocations { color: var(--ink-soft); font-size: 14px; margin: 0 0 8px; }
.lesson-page .grammar-section { margin: 44px 0 28px; }
.grammar-focus { padding-top: 22px; }
.grammar-focus + .grammar-focus { border-top: 1px solid var(--line); margin-top: 28px; }
.grammar-focus h3 { font-family: Georgia, "Times New Roman", serif; font-size: 26px; letter-spacing: -.025em; margin: 0 0 12px; }
.grammar-focus__explanation { font-size: 17px; line-height: 1.75; margin: 0 0 20px; max-width: 75ch; }
.grammar-patterns { display: grid; gap: 20px; grid-template-columns: repeat(3, minmax(0, 1fr)); margin: 24px 0; }
.grammar-patterns strong { border-left: 1px solid var(--line); color: var(--accent-deep); font-family: Georgia, "Times New Roman", serif; font-size: clamp(23px, 3vw, 32px); padding: 8px 20px; }
.grammar-patterns strong:first-child { border-left: 0; padding-left: 0; }
.grammar-example { align-items: baseline; border-bottom: 1px solid var(--line); display: grid; gap: 16px 24px; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); padding: 16px 0; }
.grammar-example:last-child { border-bottom: 0; }
.grammar-example p { line-height: 1.65; margin: 0; }
.grammar-example p[lang="en"] { font-family: Georgia, "Times New Roman", serif; font-size: 21px; }
.grammar-example p[lang="zh-CN"] { color: var(--ink-soft); font-size: 16px; }
.lesson-page .lesson-finish { background: transparent; border: 0; border-radius: 0; box-shadow: none; display: block; margin: 28px 0 40px; max-width: none; padding: 0; }
.lesson-page .lesson-finish__subtitle { font-size: 16px; margin: 10px 0 28px; }
.lesson-finish__body { align-items: center; display: flex; gap: 32px; }
.lesson-finish__summary { flex: 1; min-width: 0; }
.lesson-page .lesson-finish__count { align-items: baseline; display: flex; flex-wrap: wrap; gap: 12px 24px; margin: 0 0 16px; }
.lesson-finish__count strong { color: var(--ink); font-family: Georgia, "Times New Roman", serif; font-size: 52px; font-variant-numeric: lining-nums tabular-nums; font-weight: 700; line-height: 1.1; white-space: nowrap; }
.lesson-finish__count strong > span { color: var(--accent-deep); font: inherit; }
.lesson-finish__count > span { color: var(--ink-soft); font-size: 16px; }
.lesson-finish__progress { background: var(--line); height: 6px; overflow: hidden; }
.lesson-finish__progress > span { background: var(--accent); display: block; height: 100%; }
.lesson-page .lesson-finish__hint { font-size: 16px; line-height: 1.65; margin: 16px 0 0; }
.lesson-finish__body > .button { border-radius: 3px; flex: none; min-height: 48px; padding: 12px 24px; }
.lesson-finish__body > .button:disabled { background: var(--line); color: var(--ink-soft); cursor: not-allowed; opacity: 1; }
.word-popover { border-radius: 4px; box-sizing: border-box; gap: 10px; max-height: min(460px, calc(100vh - 32px)); max-width: calc(100vw - 32px); overflow-y: auto; padding: 20px; position: fixed; transform: translateX(var(--popover-offset-x, 0px)); width: 290px; }
.word-popover__top { align-items: baseline; flex-wrap: wrap; gap: 4px 8px; padding-right: 20px; }
.word-popover__top strong { font-size: 27px; line-height: 1.2; overflow-wrap: anywhere; }
.word-popover__pos { color: var(--ink-soft); font: 12px/1.5 Arial, sans-serif; }
.word-popover__ipa { color: var(--accent-deep); font: 16px/1.4 Arial, sans-serif; }
.word-popover__form { color: var(--ink-soft); font: 13px/1.5 Arial, "Microsoft YaHei", sans-serif; }
.word-popover__meaning { color: var(--ink); font: 17px/1.5 Arial, "Microsoft YaHei", sans-serif; }
.word-popover__close { align-items: center; background: transparent; border: 0; color: var(--ink-soft); cursor: pointer; display: flex; height: 32px; justify-content: center; padding: 5px; position: absolute; right: 8px; top: 8px; width: 32px; }
.word-popover__close svg { height: 18px; width: 18px; }
.word-popover__example { border-left: 0; border-top: 1px solid var(--line); color: var(--ink); font: italic 18px/1.55 Georgia, "Times New Roman", serif; margin: 2px 0 0; padding: 12px 0 0; }
.word-popover__example .zh-hint { color: var(--ink-soft); font: 14px/1.5 Arial, "Microsoft YaHei", sans-serif; margin-top: 4px; }
.word-popover__actions { align-items: center; display: flex; flex-wrap: wrap; gap: 8px; justify-content: space-between; }
.word-popover__audio, .word-popover__mark { align-items: center; background: transparent; border: 0; border-radius: 3px; color: var(--accent-deep); cursor: pointer; display: inline-flex; font: 14px/1.4 Arial, "Microsoft YaHei", sans-serif; gap: 6px; margin: 0; min-height: 40px; padding: 6px 0; white-space: nowrap; }
.word-popover__audio svg { flex: none; height: 20px; width: 20px; }
.word-popover__close:hover, .word-popover__audio:hover, .word-popover__mark:hover { background: var(--accent-pale); }
.word-popover button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.lesson-page .answer-options, .review-page .answer-options { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.lesson-page .answer-option, .review-page .answer-option { align-items: center; background: var(--paper); border-radius: 3px; display: flex; font-family: Georgia, "Times New Roman", serif; font-size: 18px; gap: 14px; min-height: 60px; padding: 14px 16px; }
.answer-option > span:not(.answer-option__marker) { overflow-wrap: anywhere; }
.answer-option__marker { color: #187348; flex: none; height: 20px; width: 20px; }
.answer-option__radio { border: 1px solid var(--ink-soft); border-radius: 50%; display: block; height: 18px; position: relative; width: 18px; }
.answer-option.is-selected .answer-option__radio::after { background: currentColor; border-radius: 50%; content: ""; inset: 3px; position: absolute; }
.lesson-page .answer-option.is-correct, .review-page .answer-option.is-correct { background: #f1f9f5; border-color: #187348; }
.lesson-page .answer-option.is-wrong, .review-page .answer-option.is-wrong { background: #fff7f4; border-color: #a44228; }
.answer-option.is-correct .answer-option__radio { border-color: #187348; color: #187348; }
.answer-option.is-wrong .answer-option__radio { border-color: #a44228; color: #a44228; }
.answer-option__label { color: #187348; font: 12px/1.4 Arial, "Microsoft YaHei", sans-serif; margin-left: auto; }
.exercise-feedback, .exercise-feedback.is-correct, .exercise-feedback.is-wrong { background: transparent; border: 0; border-radius: 0; color: var(--ink); font-size: 16px; line-height: 1.65; margin: 16px 0 0; padding: 0; }
.exercise-feedback__status { align-items: center; display: flex; gap: 10px; margin-bottom: 6px; }
.exercise-feedback__status svg { height: 21px; width: 21px; }
.exercise-feedback.is-correct .exercise-feedback__status { color: #187348; }
.exercise-feedback.is-wrong .exercise-feedback__status { color: #a44228; }
.exercise-feedback p { margin: 4px 0 0; }
.exercise-feedback__explanation { color: var(--ink-soft); }
.backup-section { border: 0; border-radius: 0; margin: 24px 0 40px; max-width: 760px; padding: 0; }
.backup-section h2 { font-family: Georgia, "Times New Roman", serif; font-size: 30px; }
.backup-section > p:not(.eyebrow) { font-size: 16px; }
.backup-actions .button { border-radius: 3px; min-height: 44px; padding: 8px 18px; }
.backup-reset { color: #a44228; display: block; margin-top: 20px; }
.backup-confirmation { align-items: center; background: #fff7f4; display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; margin-top: 10px; padding: 16px; }
.backup-confirmation p { color: #a44228; flex: 1 1 280px; font-size: 14px; line-height: 1.7; margin: 0; }
.button--danger { background: #a44228; }
.button--danger:hover { background: #84331e; }
.backup-feedback { color: #187348; font-size: 15px; line-height: 1.6; margin: 18px 0 0; }
.backup-feedback.is-wrong { color: #a44228; }
.empty-state { background: transparent; border: 0; border-radius: 0; box-shadow: none; margin: 32px auto; padding: 36px 16px; }
.empty-state h1, .empty-state h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(26px, 3vw, 38px); letter-spacing: -.025em; }
.empty-state p { font-size: 16px; line-height: 1.65; }
.empty-state .button { border-radius: 3px; min-height: 44px; }
.empty-state__detail { overflow-wrap: anywhere; }
.loading-state__spinner { animation: hms-loading 1s linear infinite; border: 3px solid var(--line); border-radius: 50%; border-top-color: var(--accent); display: block; height: 36px; margin: 28px auto 20px; width: 36px; }
.backup-confirmation[hidden], .backup-feedback[hidden] { display: none; }
@keyframes hms-loading { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) { .loading-state__spinner { animation: none; } }
@media (max-width: 1000px) {
  .lesson-vocabulary__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 700px) {
  .lesson-page .lesson-heading__meta { align-items: baseline; display: flex; gap: 16px; justify-content: space-between; text-align: left; width: 100%; }
  .lesson-heading__meta .lesson-goals { max-width: 240px; width: auto; }
  .lesson-heading__meta .lesson-goals summary { text-align: right; }
  .grammar-patterns { gap: 10px; }
  .grammar-patterns strong { font-size: 22px; padding: 4px 10px; }
  .grammar-example { gap: 4px; grid-template-columns: minmax(0, 1fr); }
  .lesson-finish__body { align-items: stretch; flex-direction: column; gap: 24px; }
  .lesson-page .answer-options, .review-page .answer-options { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 420px) {
  .lesson-vocabulary__grid { grid-template-columns: minmax(0, 1fr); }
  .lesson-vocabulary__grid .vocabulary-item__preview { min-height: 132px; }
  .grammar-patterns { grid-template-columns: minmax(0, 1fr); }
  .grammar-patterns strong { border-left: 0; padding: 4px 0; }
}
@media (max-width: 850px) {
  .lesson-page .reading-layout { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .lesson-page .reading-vocab-panel { border-left: 0; border-top: 1px solid var(--line); padding: 18px 0 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px 20px; }
  .lesson-page .reading-vocab-panel h3 { grid-column: 1 / -1; }
}
@media (max-width: 700px) {
  .lesson-page .lesson-heading { flex-direction: column; gap: 5px; }
  .lesson-page .lesson-heading h1 { font-size: 33px; }
  .lesson-goals { max-width: none; padding: 0; width: 100%; }
  .lesson-goals summary { text-align: left; }
  .lesson-page .lesson-stepper__item a { font-size: 13px; }
  .lesson-page .reading-dialogue { gap: 10px; grid-template-columns: 54px minmax(0, 1fr); }
  .lesson-page .reading-sentence--dialogue > .reading-sentence__zh { margin-left: 64px; }
  .lesson-page .reading-sentence__de { font-size: 21px; }
  .lesson-page .reading-controls { gap: 8px; }
  .lesson-page .reading-time { order: 2; }
  .lesson-page .reading-progress { flex-basis: calc(100% - 110px); order: 2; }
  .lesson-page .reading-vocab-item strong { font-size: 21px; }
}
.review-page__heading { align-items: end; display: flex; gap: 24px; justify-content: space-between; margin-bottom: 26px; }
.review-page__heading h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(48px, 6vw, 70px); letter-spacing: -.05em; }
.review-page__summary { text-align: right; }
.review-page__summary strong { font-family: Georgia, "Times New Roman", serif; font-size: clamp(18px, 2vw, 25px); }
.review-page__summary p { color: var(--ink-soft); margin: 3px 0 0; }
.review-page__words { grid-template-columns: repeat(var(--review-columns, 4), minmax(0, 1fr)); margin-bottom: 0; }
.review-page .exercise-card { background: transparent; border: 0; border-radius: 0; margin: 0; max-width: none; padding: 28px 20px 0; }
.review-page .exercise-card h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(23px, 2.6vw, 32px); letter-spacing: -.03em; margin-bottom: 8px; }
.review-page .answer-options { gap: 12px; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.review-page .answer-option { background: var(--paper); border-color: #cfd6e5; border-radius: 4px; font-family: Georgia, "Times New Roman", serif; min-height: 64px; text-align: center; }
.review-page .answer-option:hover { background: #f8faff; }

@media (max-width: 760px) {
  .review-page__heading { align-items: flex-start; flex-direction: column; gap: 12px; margin-bottom: 20px; }
  .review-page__heading h1 { font-size: 52px; }
  .review-page__summary { text-align: left; }
  .review-page .answer-options { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .vocabulary-page__heading { align-items: stretch; flex-direction: column; gap: 18px; }
  .vocabulary-page__heading h1 { font-size: 52px; }
  .vocabulary-page__search { max-width: none; }
  .vocabulary-page__levels a { min-height: 60px; }
  .vocabulary-page__list-heading { align-items: flex-start; flex-direction: column; gap: 8px; padding-top: 20px; }
  .vocabulary-page__list-heading p { margin: 0; }
  .vocabulary-page__statuses { gap: 22px; }
  .vocabulary-page__statuses a { padding-bottom: 10px; }
  .vocabulary-page__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .vocabulary-item:nth-child(4n+1) { border-left: 1px solid var(--line); }
  .vocabulary-item:nth-child(2n+1) { border-left: 0; }
  .vocabulary-item__preview { min-height: 150px; padding: 15px; }
  .vocabulary-item__word { gap: 5px; }
  .vocabulary-item__word strong { font-size: 23px; }
  .vocabulary-item__detail { padding: 12px 15px 15px; }
}
@media (max-width: 760px) {
  .lesson-page .lesson-vocabulary__grid .vocabulary-item { border: 1px solid var(--line); }
  .lesson-page .lesson-vocabulary__grid .vocabulary-item.is-open { border-color: var(--accent); }
}
@media (max-width: 420px) {
  .lesson-page .lesson-vocabulary__grid { grid-template-columns: minmax(0, 1fr); }
}