/* Lesson shell v2: common learning behavior and layout, with lesson-owned skin variables. */
:root {
  --lesson-bg: #f2ecdf;
  --lesson-paper: #fffaf0;
  --lesson-ink: #19352c;
  --lesson-muted: #62736c;
  --lesson-accent: #b34f32;
  --lesson-accent-soft: #f0d8c6;
  --lesson-gold: #e8a32a;
  --lesson-deep: #214c3d;
  --lesson-line: rgba(25, 53, 44, .18);
  --lesson-shadow: 0 22px 70px rgba(38, 43, 34, .12);
  --lesson-shell-header-height: 64px;
  --lesson-shell-max: 1120px;
  --lesson-sans: "Noto Sans SC Local", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --lesson-serif: "Noto Serif SC Local", "Noto Serif SC", "Songti SC", STSong, serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  color-scheme: light;
  scroll-behavior: smooth;
  background: var(--lesson-bg);
}

body[data-lesson-shell="v2"] {
  min-width: 0;
  margin: 0;
  color: var(--lesson-ink);
  background:
    radial-gradient(circle at 12% 5%, rgba(179, 79, 50, .1), transparent 30rem),
    linear-gradient(180deg, #f7f1e6 0, var(--lesson-bg) 42rem);
  font-family: var(--lesson-sans);
  font-size: 16px;
  line-height: 1.8;
}

body[data-lesson-shell="v2"] button,
body[data-lesson-shell="v2"] input {
  font: inherit;
}

body[data-lesson-shell="v2"] audio[data-audio-kind="textbook-readaloud"] {
  display: none;
}

body[data-lesson-shell="v2"] button,
body[data-lesson-shell="v2"] a {
  -webkit-tap-highlight-color: transparent;
}

body[data-lesson-shell="v2"] button:focus-visible,
body[data-lesson-shell="v2"] a:focus-visible,
body[data-lesson-shell="v2"] input:focus-visible {
  outline: 3px solid #e8a32a;
  outline-offset: 3px;
}

.lesson-topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  color: #fffdf5;
  background: rgba(24, 66, 53, .97);
  border-bottom: 1px solid rgba(255, 255, 255, .16);
  backdrop-filter: blur(14px);
}

.topbar-inner {
  width: min(var(--lesson-shell-max), calc(100% - 32px));
  min-height: 64px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.return-link {
  min-width: 44px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: inherit;
  font-weight: 800;
  text-decoration: none;
}

.return-link::before {
  content: "←";
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, .58);
  border-radius: 50%;
}

.topbar-meta {
  color: rgba(255, 255, 255, .76);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .04em;
  text-align: right;
}

.lesson-main {
  width: min(var(--lesson-shell-max), calc(100% - 32px));
  margin: 0 auto;
}

.lesson-hero {
  margin: clamp(24px, 5vw, 58px) 0 24px;
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, .85fr);
  overflow: hidden;
  background: var(--lesson-paper);
  border: 1px solid var(--lesson-line);
  border-radius: 28px;
  box-shadow: var(--lesson-shadow);
}

.hero-copy {
  min-width: 0;
  padding: clamp(32px, 6vw, 72px);
  align-self: center;
}

.lesson-mark,
.section-kicker {
  margin: 0;
  color: var(--lesson-accent);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: .16em;
  text-transform: uppercase;
}

.hero-copy h1 {
  margin: 10px 0 18px;
  font-family: var(--lesson-serif);
  font-size: clamp(52px, 8vw, 88px);
  font-weight: 800;
  letter-spacing: .06em;
  line-height: 1.02;
}

.hero-lead {
  max-width: 28em;
  margin: 0;
  color: var(--lesson-muted);
  font-size: clamp(17px, 2vw, 21px);
}

.learning-path {
  margin: 28px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
}

.learning-path li {
  padding: 6px 11px;
  color: var(--lesson-deep);
  background: var(--lesson-accent-soft);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 850;
}

.hero-visual {
  position: relative;
  min-height: 460px;
  margin: 0;
  overflow: hidden;
  background: #d9c5a8;
}

.hero-visual img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
  object-position: 50% 45%;
}

.hero-visual figcaption {
  position: absolute;
  right: 16px;
  bottom: 16px;
  max-width: calc(100% - 32px);
  padding: 7px 11px;
  color: #fff;
  background: rgba(25, 53, 44, .86);
  border-radius: 999px;
  font-size: 12px;
}

.reader-dock {
  position: sticky;
  top: var(--lesson-shell-header-height);
  z-index: 30;
  margin: 0 0 26px;
  color: #fffdf5;
  background: rgba(25, 53, 44, .96);
  border: 1px solid rgba(255, 255, 255, .16);
  border-radius: 18px;
  box-shadow: 0 16px 38px rgba(25, 53, 44, .2);
  backdrop-filter: blur(14px);
}

.reader-inner {
  min-height: 76px;
  display: grid;
  grid-template-columns: auto auto minmax(180px, 1fr);
  align-items: center;
  gap: 14px;
  padding: 10px 14px;
}

.mode-switch,
.reader-actions,
.recite-actions {
  display: flex;
  align-items: center;
  gap: 7px;
}

.mode-switch {
  padding: 4px;
  background: rgba(255, 255, 255, .1);
  border: 1px solid rgba(255, 255, 255, .18);
  border-radius: 999px;
}

.mode-switch button,
.reader-actions button,
.recite-actions button {
  min-width: 44px;
  min-height: 44px;
  padding: 0 14px;
  cursor: pointer;
  border-radius: 999px;
  font-weight: 850;
}

.mode-switch button {
  color: rgba(255, 255, 255, .76);
  background: transparent;
  border: 0;
}

.mode-switch button[aria-pressed="true"] {
  color: var(--lesson-deep);
  background: var(--lesson-paper);
}

.reader-actions button {
  color: var(--lesson-deep);
  background: #fffaf0;
  border: 0;
}

.reader-actions button[data-action="audio-restart"] {
  color: #fff;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, .45);
}

.reader-progress {
  min-width: 0;
  display: grid;
  grid-template-columns: minmax(90px, 1fr) auto;
  align-items: center;
  gap: 10px;
}

.reader-progress input[type="range"] {
  width: 100%;
  min-height: 44px;
  margin: 0;
  accent-color: #e7a143;
  cursor: pointer;
}

.reader-time {
  min-width: 6.7em;
  color: rgba(255, 255, 255, .78);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  text-align: right;
}

.audio-status {
  grid-column: 1 / -1;
  min-height: 1.3em;
  margin: -8px 0 0;
  color: rgba(255, 255, 255, .7);
  font-size: 12px;
}

.lesson-section {
  margin: 0 0 26px;
  padding: clamp(26px, 5vw, 56px);
  background: rgba(255, 250, 240, .9);
  border: 1px solid var(--lesson-line);
  border-radius: 24px;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 28px;
}

.section-heading h2 {
  margin: 7px 0 8px;
  font-family: var(--lesson-serif);
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.2;
}

.section-heading p:last-child {
  margin: 0;
  color: var(--lesson-muted);
}

.learning-goals,
.pronunciation-grid,
.note-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.goal,
.sound-card,
.word-note {
  min-width: 0;
  padding: 17px;
  background: #f4ecde;
  border: 1px solid rgba(25, 53, 44, .1);
  border-radius: 14px;
}

.goal strong,
.sound-card strong,
.word-note strong {
  color: var(--lesson-deep);
}

.goal span,
.sound-card span,
.word-note span {
  display: block;
  margin-top: 3px;
  color: var(--lesson-muted);
  font-size: 14px;
}

.original-card {
  position: relative;
  margin: 24px 0;
  padding: clamp(24px, 5vw, 48px);
  overflow: hidden;
  background:
    linear-gradient(90deg, transparent 0 2.9rem, rgba(179, 79, 50, .12) 2.9rem 3rem, transparent 3rem),
    repeating-linear-gradient(0deg, transparent 0 3.08rem, rgba(25, 53, 44, .08) 3.08rem 3.12rem),
    #fffdf7;
  border: 1px solid rgba(25, 53, 44, .2);
  border-radius: 18px;
}

.original-card::before {
  content: "原文";
  position: absolute;
  top: 0;
  right: 0;
  padding: 7px 13px;
  color: #fff;
  background: var(--lesson-accent);
  border-radius: 0 16px 0 14px;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: .12em;
}

.reading-unit {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px 16px;
  padding: 22px 0;
  border-bottom: 1px solid var(--lesson-line);
}

.reading-unit:first-child {
  padding-top: 0;
}

.reading-unit:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.reading-unit > [data-paragraph-id] {
  grid-column: 1;
  margin: 0;
}

.reading-unit > .reading-unit-audio {
  grid-column: 2;
  align-self: start;
  min-width: 112px;
  min-height: 44px;
  padding: 8px 13px;
  color: var(--lesson-deep);
  background: var(--lesson-accent-soft);
  border: 1px solid var(--lesson-line);
  border-radius: 999px;
  font-family: var(--lesson-sans);
  font-size: 14px;
  font-weight: 850;
  line-height: 1.3;
  cursor: pointer;
}

.reading-unit > .reading-unit-audio[aria-pressed="true"] {
  color: #fffdf7;
  background: var(--lesson-deep);
  border-color: var(--lesson-deep);
}

.reading-unit.has-visual {
  grid-template-columns: minmax(0, 1fr) minmax(250px, .72fr);
}

.reading-unit > figure {
  grid-column: 2;
  grid-row: 1 / span 2;
  align-self: start;
  min-width: 0;
  margin: 0;
  overflow: hidden;
  background: #fffdf7;
  border: 1px solid var(--lesson-line);
  border-radius: 14px;
  font-family: var(--lesson-sans);
  font-size: 14px;
  line-height: 1.65;
}

.reading-unit > figure img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: contain;
}

.reading-unit > figure figcaption {
  padding: 11px 13px;
  color: var(--lesson-muted);
  font-size: 13px;
}

.reading-unit > figure figcaption b {
  display: block;
  color: var(--lesson-deep);
}

[data-testid="textbook-original"] {
  margin: 0;
  font-family: var(--lesson-serif);
  font-size: clamp(24px, 3.4vw, 36px);
  font-weight: 650;
  letter-spacing: .04em;
  line-height: 2.05;
  transition: opacity .18s ease;
}

body[data-mode="recite"] [data-testid="textbook-original"] {
  visibility: hidden;
}

.pause-guide {
  margin: 18px 0 28px;
  padding: 16px 18px;
  color: var(--lesson-deep);
  background: var(--lesson-accent-soft);
  border-left: 4px solid var(--lesson-accent);
  border-radius: 0 12px 12px 0;
  font-family: var(--lesson-serif);
  font-size: 18px;
  line-height: 2;
}

.pause-guide b {
  color: var(--lesson-accent);
}

.pronunciation-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.sound-card strong {
  font-family: var(--lesson-serif);
  font-size: 28px;
}

.sound-card em {
  margin-left: 7px;
  color: var(--lesson-accent);
  font-style: normal;
  font-weight: 900;
}

.note-grid {
  margin-top: 12px;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.story-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.story-step {
  min-width: 0;
  margin: 0;
  overflow: hidden;
  background: #fffdf7;
  border: 1px solid var(--lesson-line);
  border-radius: 14px;
}

.story-step img {
  width: 100%;
  aspect-ratio: 4 / 5;
  display: block;
  object-fit: cover;
}

.story-step figcaption {
  padding: 12px;
  color: var(--lesson-muted);
  font-size: 14px;
}

.story-step b {
  display: block;
  color: var(--lesson-deep);
  font-size: 15px;
}

/*
 * Textbook prose is one continuous reading surface. Lesson-owned skins may
 * decorate headings and controls, but must not reintroduce the old
 * section -> original card -> paragraph card -> image card nesting.
 * Classical-poetry pages keep their poem-specific composition.
 */
body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section {
  padding: clamp(32px, 5vw, 56px) 0;
  background: transparent;
  border: 0;
  border-radius: 0;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .section-heading {
  max-width: 900px;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .original-card {
  margin: 28px 0 0;
  padding: 0;
  overflow: visible;
  background: transparent;
  border: 0;
  border-radius: 0;
  box-shadow: none;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .original-card::before {
  display: none;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section [data-testid="textbook-original"] {
  width: 100%;
  max-width: none;
  padding: 0;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph-list, .nature-list) {
  gap: 0;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph, .nature-paragraph) {
  margin: 0;
  padding: clamp(24px, 3vw, 36px) 0;
  background: transparent;
  border: 0;
  border-top: 1px solid var(--lesson-line);
  border-radius: 0;
  box-shadow: none;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph, .nature-paragraph):first-child {
  padding-top: 0;
  border-top: 0;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section [data-testid="textbook-original"] figure {
  overflow: visible;
  background: transparent;
  border: 0;
  border-radius: 0;
  box-shadow: none;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section [data-testid="textbook-original"] figure img {
  border-radius: 16px;
}

body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section [data-testid="textbook-original"] figure figcaption {
  padding: 9px 2px 0;
  background: transparent;
}

.meaning-note {
  margin: 18px 0 0;
  color: var(--lesson-muted);
  font-size: 14px;
}

.recite-panel {
  scroll-margin-top: calc(var(--lesson-shell-header-height) + 100px);
  color: #fffdf5;
  background:
    radial-gradient(circle at 90% 10%, rgba(232, 163, 42, .18), transparent 22rem),
    var(--lesson-deep);
  border-color: rgba(255, 255, 255, .12);
}

.recite-panel .section-kicker,
.recite-panel .section-heading p,
.recite-panel .recite-hint {
  color: rgba(255, 255, 255, .72);
}

.recite-prompt {
  margin: 22px 0;
  padding: clamp(22px, 4vw, 38px);
  color: #fffdf5;
  background: rgba(255, 255, 255, .08);
  border: 1px solid rgba(255, 255, 255, .18);
  border-radius: 16px;
  font-family: var(--lesson-serif);
  font-size: clamp(21px, 3vw, 30px);
  line-height: 2;
}

.recite-hint {
  min-height: 2em;
  margin: 0 0 16px;
  font-family: var(--lesson-serif);
  font-size: 18px;
}

.recite-answer {
  margin: 0 0 18px;
  padding: 18px 20px;
  color: var(--lesson-deep);
  background: #fffaf0;
  border-left: 4px solid var(--lesson-gold);
  border-radius: 12px;
  font-family: var(--lesson-serif);
  font-size: clamp(19px, 2.5vw, 24px);
  line-height: 1.9;
}

.recite-answer[hidden] {
  display: none;
}

[data-testid="textbook-original"] {
  scroll-margin-top: calc(var(--lesson-shell-header-height) + 100px);
}

.recite-actions {
  flex-wrap: wrap;
}

.recite-actions button {
  color: var(--lesson-deep);
  background: #fffaf0;
  border: 0;
}

.recite-actions button.secondary {
  color: #fff;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, .5);
}

.video-card {
  display: grid;
  grid-template-columns: minmax(220px, .72fr) minmax(0, 1.28fr);
  gap: 22px;
  align-items: center;
}

.video-card video {
  width: 100%;
  max-height: 520px;
  display: block;
  background: #142b24;
  border-radius: 16px;
}

.video-copy h2 {
  margin: 8px 0;
  font-family: var(--lesson-serif);
  font-size: clamp(27px, 3.5vw, 40px);
  line-height: 1.25;
}

.video-copy p:last-child {
  color: var(--lesson-muted);
}

.disclosure {
  margin: 24px 0;
  color: var(--lesson-muted);
  font-size: 13px;
}

.lesson-footer {
  margin-top: 32px;
  padding: 22px 0 46px;
  display: flex;
  justify-content: space-between;
  gap: 18px;
  color: var(--lesson-muted);
  border-top: 1px solid var(--lesson-line);
  font-size: 13px;
}

.lesson-footer a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  color: var(--lesson-deep);
  font-weight: 850;
}

[hidden] {
  display: none !important;
}

@media (max-width: 900px) {
  .lesson-hero {
    grid-template-columns: minmax(0, 1fr) minmax(240px, .7fr);
  }

  .hero-copy {
    padding: 38px;
  }

  .reader-inner {
    grid-template-columns: 1fr auto;
  }

  .reader-progress {
    grid-column: 1 / -1;
  }

  .story-strip {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 680px) {
  :root {
    --lesson-shell-header-height: 58px;
  }

  .topbar-inner,
  .lesson-main {
    width: min(100% - 22px, var(--lesson-shell-max));
  }

  .topbar-inner {
    min-height: 58px;
  }

  .topbar-meta {
    max-width: 11em;
    line-height: 1.35;
  }

  .lesson-hero {
    grid-template-columns: 1fr;
    border-radius: 20px;
  }

  .hero-copy {
    padding: 26px 23px;
  }

  .hero-copy h1 {
    font-size: clamp(48px, 17vw, 68px);
  }

  .hero-visual {
    min-height: 240px;
    max-height: 280px;
  }

  .reader-dock {
    position: relative;
    top: auto;
    border-radius: 16px;
  }

  .reader-inner {
    grid-template-columns: minmax(148px, 1fr) minmax(0, 1fr);
    gap: 0 6px;
    min-height: 0;
    padding: 4px 8px 1px;
  }

  .mode-switch,
  .reader-actions {
    width: 100%;
    min-width: 0;
  }

  .mode-switch {
    gap: 2px;
    padding: 1px;
  }

  .reader-actions {
    gap: 4px;
  }

  body[data-lesson-shell="v2"] .mode-switch button,
  body[data-lesson-shell="v2"] .reader-actions button {
    min-width: 44px;
    min-height: 44px;
    flex: 1 1 0;
    padding-inline: 2px;
    overflow: hidden;
    font-size: 14px;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .reader-progress {
    grid-column: 1 / -1;
    position: static;
    display: grid;
    grid-template-columns: minmax(90px, 1fr) auto;
    gap: 4px;
    min-height: 0;
    padding: 0;
  }

  .reader-progress input[type="range"] {
    width: 100%;
    display: block;
  }

  .reader-time {
    position: static;
    min-width: 5.8em;
    padding: 0;
    color: rgba(255, 255, 255, .78);
    background: transparent;
    border-radius: 0;
    font-size: 12px;
    line-height: normal;
    white-space: normal;
  }

  .audio-status {
    /* Keep live updates available to assistive technology without taking a visual row. */
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
  }

  .lesson-section {
    padding: 25px 19px;
    border-radius: 18px;
  }

  /*
   * Mobile textbook reading follows the single-layer baseline established by
   * lessons 01–02. Keep the richer paragraph controls, but remove the nested
   * section → original card → paragraph card framing that narrows long prose.
   * Classical-poetry pages retain their deliberate poem-specific composition.
   */
  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section {
    width: calc(100% + 22px);
    margin-right: -11px;
    margin-left: -11px;
    padding: 28px 18px;
    background: transparent;
    border: 0;
    border-radius: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .section-heading {
    margin-bottom: 22px;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .original-card {
    margin: 18px 0 0;
    padding: 0;
    overflow: visible;
    background: transparent;
    border: 0;
    border-radius: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .original-card::before {
    display: none;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph-list, .nature-list) {
    gap: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph, .nature-paragraph) {
    padding: 20px 0;
    background: transparent;
    border: 0;
    border-bottom: 1px solid var(--lesson-line);
    border-radius: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section :is(.paragraph, .nature-paragraph):first-child {
    padding-top: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit,
  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit.has-visual {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
    padding: 22px 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit:first-child {
    padding-top: 0;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit > [data-paragraph-id],
  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit > .reading-unit-audio,
  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit > figure {
    grid-column: 1;
    grid-row: auto;
  }

  body[data-lesson-shell="v2"]:is(:not([data-lesson-type="classical-poetry"]), [data-reading-layout="single-layer"]) #text.lesson-section .reading-unit > .reading-unit-audio {
    width: auto;
    min-width: 0;
    justify-self: start;
  }

  .learning-goals,
  .pronunciation-grid,
  .note-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .original-card {
    padding: 34px 22px 24px;
    background: #fffdf7;
  }

  [data-testid="textbook-original"] {
    font-size: 24px;
    line-height: 2;
  }

  .story-strip {
    grid-template-columns: 1fr 1fr;
  }

  .video-card {
    grid-template-columns: 1fr;
  }

  .lesson-footer {
    flex-direction: column;
  }
}

@media (max-width: 340px) {
  .reader-inner {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .reader-progress {
    grid-column: auto;
  }
}

@media (max-width: 420px) {
  .learning-goals {
    grid-template-columns: 1fr 1fr;
  }

  .learning-goals .goal:last-child {
    grid-column: 1 / -1;
  }

  .reader-time {
    min-width: 5.8em;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}