:root {
  --lesson-paper: #f6f3eb;
  --lesson-sheet: #fffefa;
  --lesson-panel: #f1f0e9;
  --lesson-ink: #232725;
  --lesson-green: #123f33;
  --lesson-green-2: #1f6652;
  --lesson-green-wash: #e7eee9;
  --lesson-blue-gray: #63757b;
  --lesson-blue-wash: #edf1f2;
  --lesson-rule: #d7d8d1;
  --lesson-rule-strong: #bbc2bd;
  --lesson-red: #9b443b;
  --lesson-red-wash: #f7eae6;
  --bg-primary: var(--lesson-paper);
  --bg-secondary: var(--lesson-green-wash);
  --bg-card: var(--lesson-sheet);
  --bg-surface: #faf9f4;
  --text-primary: var(--lesson-ink);
  --text-secondary: #46504b;
  --text-muted: var(--lesson-blue-gray);
  --border: var(--lesson-rule);
  --border-strong: var(--lesson-rule-strong);
  --accent: var(--lesson-green-2);
  --accent-soft: #91ad9f;
  --accent-dim: var(--lesson-green);
  --accent-bg: rgba(31, 102, 82, .08);
  --red: var(--lesson-red);
  --red-dim: var(--lesson-red-wash);
  --purple: var(--lesson-green-2);
  --purple-dim: var(--lesson-green-wash);
  --bc-paper: var(--lesson-paper);
  --bc-surface: var(--lesson-sheet);
  --bc-soft: var(--lesson-green-wash);
  --bc-soft-2: var(--lesson-blue-wash);
  --bc-ink: var(--lesson-ink);
  --bc-text: #46504b;
  --bc-muted: var(--lesson-blue-gray);
  --bc-line: var(--lesson-rule);
  --bc-line-strong: var(--lesson-rule-strong);
  --bc-forest: var(--lesson-green-2);
  --bc-forest-dark: var(--lesson-green);
  --bc-teal: #426e66;
  --bc-indigo: #516b78;
  --bc-indigo-soft: var(--lesson-blue-wash);
  --bc-red: var(--lesson-red);
  --bc-red-soft: var(--lesson-red-wash);
  --bc-shadow: 0 1px 2px rgba(35, 39, 37, .05);
}

html {
  background: var(--lesson-paper);
  overflow: hidden;
}

body.bc-learning-page {
  min-width: 0;
  height: 100vh;
  display: block !important;
  overflow: hidden !important;
  color: var(--lesson-ink);
  background: var(--lesson-paper) !important;
  background-image: none !important;
}

body.bc-learning-page::before,
.bc-learning-page .hook-card::before,
.bc-learning-page .exam-technique::before,
.bc-learning-page .concept-card-wrapper::before {
  display: none !important;
  background: none !important;
}

.lesson-app-header {
  position: relative;
  z-index: 420;
  height: 62px;
  display: grid;
  grid-template-columns: minmax(205px, 1fr) auto minmax(205px, 1fr);
  align-items: center;
  gap: 18px;
  padding: 0 22px;
  border-bottom: 1px solid var(--lesson-rule-strong);
  background: var(--lesson-sheet);
}

.lesson-brand {
  min-width: 0;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--lesson-green);
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
}

.lesson-brand:hover {
  color: var(--lesson-green-2);
}

.lesson-brand-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border: 1px solid var(--lesson-green);
  border-radius: 3px;
  color: var(--lesson-sheet);
  background: var(--lesson-green);
  font-family: Georgia, serif;
  font-size: 23px;
  font-weight: 400;
}

.lesson-primary-nav {
  height: 100%;
  display: flex;
  align-items: stretch;
  gap: 4px;
}

.lesson-primary-nav a {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 0 13px;
  color: #3f4945;
  font-size: 13px;
  font-weight: 650;
  text-decoration: none;
}

.lesson-primary-nav a span {
  color: var(--lesson-blue-gray);
  font-size: 11px;
  font-weight: 500;
}

.lesson-primary-nav a:hover {
  color: var(--lesson-green);
  background: #f7f8f4;
}

.lesson-primary-nav a.active {
  color: var(--lesson-green);
}

.lesson-primary-nav a.active::after {
  content: "";
  position: absolute;
  right: 12px;
  bottom: -1px;
  left: 12px;
  height: 3px;
  background: var(--lesson-green);
}

.lesson-study-record {
  min-width: 0;
  display: inline-flex;
  align-items: center;
  justify-self: end;
  gap: 7px;
  color: var(--lesson-blue-gray);
  font-size: 12px;
  white-space: nowrap;
}

.lesson-study-record svg,
.sidebar-close svg,
.unit-header svg,
.coach-toggle svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.lesson-workspace {
  height: calc(100vh - 62px);
  display: grid;
  grid-template-columns: minmax(248px, 284px) minmax(0, 1fr) minmax(270px, 304px);
  overflow: hidden;
}

body.bc-learning-page .sidebar {
  position: relative;
  inset: auto;
  z-index: 20;
  width: auto;
  min-width: 0;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transform: none;
  border-right: 1px solid var(--lesson-rule);
  background: #efeee7 !important;
  box-shadow: none;
}

body.bc-learning-page .sidebar-header {
  min-height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 15px 17px;
  border-bottom: 1px solid var(--lesson-rule) !important;
  background: var(--lesson-sheet) !important;
}

.sidebar-title {
  color: var(--lesson-ink);
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
}

.sidebar-subtitle {
  margin-top: 2px;
  color: var(--lesson-blue-gray);
  font: 600 10.5px/1.3 var(--font-mono);
  letter-spacing: .04em;
}

.sidebar-close {
  width: 34px;
  height: 34px;
  display: none;
  place-items: center;
  border: 1px solid var(--lesson-rule);
  border-radius: 3px;
  color: var(--lesson-green);
  background: transparent;
  cursor: pointer;
}

body.bc-learning-page .sidebar-content {
  flex: 1;
  min-height: 0;
  padding: 8px 8px 20px;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.course-unit {
  border-bottom: 1px solid rgba(187, 194, 189, .58);
}

body.bc-learning-page .unit-header {
  width: 100%;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin: 0;
  padding: 9px 8px;
  border: 0;
  border-radius: 2px;
  color: var(--lesson-ink);
  background: transparent;
  text-align: left;
  cursor: pointer;
}

body.bc-learning-page .unit-header:hover {
  background: rgba(255, 254, 250, .7);
}

.unit-header span {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.unit-header b {
  color: var(--lesson-green);
  font-size: 12px;
  font-weight: 750;
}

.unit-header em {
  overflow: hidden;
  color: #4b5550;
  font-size: 11.5px;
  font-style: normal;
  line-height: 1.35;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.unit-header svg {
  flex: 0 0 auto;
  transition: transform 160ms ease;
}

.unit-header[aria-expanded="true"] svg {
  transform: rotate(90deg);
}

.course-topic-list[hidden] {
  display: none;
}

.course-topic-list {
  display: grid;
  gap: 1px;
  padding: 0 0 8px;
}

body.bc-learning-page .sidebar-link {
  min-width: 0;
  min-height: 40px;
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr) auto;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 7px 8px;
  border-left: 2px solid transparent;
  border-radius: 2px !important;
  color: #4a544f;
  background: transparent;
  font-size: 12px;
  line-height: 1.3;
  text-decoration: none;
}

.topic-rail-meta {
  display: grid;
  justify-items: end;
  gap: 4px;
}

.topic-exam-count {
  color: var(--lesson-blue-gray);
  font: 650 9px/1 var(--font-mono);
  white-space: nowrap;
}

body.bc-learning-page .sidebar-link:hover {
  color: var(--lesson-green) !important;
  background: rgba(255, 254, 250, .7) !important;
}

body.bc-learning-page .sidebar-link.active {
  border-left-color: var(--lesson-green);
  color: var(--lesson-green) !important;
  background: #dfe8e1 !important;
  font-weight: 650;
}

.topic-code {
  color: var(--lesson-green);
  font: 700 10.5px/1 var(--font-mono);
}

.topic-name {
  min-width: 0;
}

.topic-mastery-dots,
.coach-mastery-dots {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.mastery-dot {
  width: 8px;
  height: 8px;
  display: inline-block;
  border: 1px solid #aeb8b2;
  border-radius: 50%;
  background: transparent;
}

.mastery-dot.filled {
  border-color: var(--lesson-green-2);
  background: var(--lesson-green-2);
}

.mastery-dot.filled.developing,
.mastery-dot.filled.fragile {
  border-color: #68848a;
  background: #68848a;
}

.mastery-dot.filled.support {
  border-color: var(--lesson-red);
  background: var(--lesson-red);
}

.outline-evidence-key {
  display: grid;
  gap: 7px;
  padding: 12px 14px 14px;
  border-top: 1px solid var(--lesson-rule);
  color: var(--lesson-blue-gray);
  background: var(--lesson-sheet);
  font-size: 10px;
}

.outline-evidence-key span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.outline-evidence-key .mastery-dot:nth-last-of-type(1) {
  margin-right: 4px;
}

.sidebar-backdrop {
  display: none;
}

body.bc-learning-page .content-wrapper {
  min-width: 0;
  width: auto;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  overflow-y: auto;
  position: relative;
  background: var(--lesson-paper);
  scrollbar-gutter: stable;
}

body.bc-learning-page .top-bar {
  position: sticky !important;
  top: 0;
  z-index: 120;
  min-height: 54px !important;
  height: 54px !important;
  flex: 0 0 54px;
  gap: 14px !important;
  padding: 0 20px !important;
  border-bottom: 1px solid var(--lesson-rule) !important;
  background: rgba(255, 254, 250, .97) !important;
  box-shadow: none !important;
  backdrop-filter: none;
}

body.bc-learning-page .top-bar-left {
  min-width: 0;
  gap: 10px !important;
}

body.bc-learning-page .module-title {
  min-width: 0;
  display: flex !important;
  align-items: baseline;
  gap: 7px;
  overflow: hidden;
  color: var(--lesson-ink) !important;
  font-family: var(--font-body) !important;
  font-size: 12px !important;
  font-weight: 550 !important;
  white-space: nowrap;
}

.module-title span,
.module-title b {
  color: var(--lesson-green);
  font-weight: 700;
}

.module-title i {
  color: var(--lesson-rule-strong);
  font-style: normal;
}

body.bc-learning-page .top-bar-right {
  flex-wrap: nowrap !important;
  gap: 8px !important;
}

body.bc-learning-page .top-link {
  min-height: 34px !important;
  padding: 5px 8px !important;
  border-radius: 3px !important;
  font-size: 11.5px !important;
}

body.bc-learning-page .lang-toggle {
  display: inline-flex;
  gap: 0;
  margin: 0 !important;
  padding: 0;
  border: 1px solid var(--lesson-rule-strong);
  border-radius: 3px;
  background: var(--lesson-sheet);
  overflow: hidden;
}

body.bc-learning-page .lang-btn {
  min-height: 32px;
  padding: 4px 10px;
  border: 0 !important;
  border-right: 1px solid var(--lesson-rule) !important;
  border-radius: 0 !important;
  color: #4b5550 !important;
  background: var(--lesson-sheet) !important;
  box-shadow: none !important;
  font-size: 11.5px;
}

body.bc-learning-page .lang-btn:last-child {
  border-right: 0 !important;
}

body.bc-learning-page .lang-btn.active {
  color: var(--lesson-sheet) !important;
  background: var(--lesson-green) !important;
}

.mobile-menu-btn {
  flex: 0 0 auto;
  display: none;
  width: 34px;
  height: 34px;
  border: 1px solid var(--lesson-rule);
  border-radius: 3px;
  color: var(--lesson-green);
  background: transparent;
}

.lesson-reading-state {
  position: sticky;
  top: 54px;
  z-index: 110;
  min-width: 0;
  display: grid;
  grid-template-columns: auto minmax(90px, 1fr) auto;
  align-items: center;
  gap: 9px 12px;
  padding: 8px 20px;
  border-bottom: 1px solid var(--lesson-rule);
  background: rgba(246, 243, 235, .97);
}

.lesson-reading-copy {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #4b5550;
  font-size: 11.5px;
  white-space: nowrap;
}

.lesson-reading-copy strong {
  color: var(--lesson-green);
  font: 700 11px/1 var(--font-mono);
}

.lesson-reading-state progress,
.coach-section progress {
  width: 100%;
  height: 6px;
  overflow: hidden;
  appearance: none;
  border: 0;
  border-radius: 0;
  background: #dfe2dd;
}

.lesson-reading-state progress::-webkit-progress-bar,
.coach-section progress::-webkit-progress-bar {
  background: #dfe2dd;
}

.lesson-reading-state progress::-webkit-progress-value,
.coach-section progress::-webkit-progress-value {
  background: var(--lesson-green-2);
}

.lesson-reading-state progress::-moz-progress-bar,
.coach-section progress::-moz-progress-bar {
  background: var(--lesson-green-2);
}

#lesson-mark-read {
  min-height: 32px;
  padding: 5px 9px;
  border: 1px solid var(--lesson-green-2);
  border-radius: 3px;
  color: var(--lesson-green);
  background: transparent;
  font-size: 11px;
  font-weight: 700;
  cursor: pointer;
}

#lesson-mark-read:hover,
#lesson-mark-read.marked {
  color: var(--lesson-sheet);
  background: var(--lesson-green);
}

.lesson-reading-state small {
  grid-column: 1 / -1;
  color: var(--lesson-blue-gray);
  font-size: 10px;
  line-height: 1.25;
}

body.bc-learning-page .main-container {
  width: 100% !important;
  max-width: 940px !important;
  min-width: 0;
  margin: 0 auto !important;
  padding: 24px 30px 112px !important;
}

body.bc-learning-page .topic-hero {
  margin: 0 0 18px;
  padding: 0 0 18px;
  border: 0 !important;
  border-bottom: 2px solid var(--lesson-green) !important;
  border-radius: 0 !important;
  background: transparent !important;
  box-shadow: none !important;
}

body.bc-learning-page .topic-kicker {
  margin-bottom: 7px;
  color: var(--lesson-green-2) !important;
  font-size: 10.5px !important;
  letter-spacing: .08em !important;
}

.topic-kicker span {
  margin: 0 4px;
  color: var(--lesson-rule-strong);
}

body.bc-learning-page .topic-hero h1 {
  margin: 0 0 7px;
  color: var(--lesson-ink);
  font-size: clamp(28px, 3vw, 39px);
  font-weight: 650;
  line-height: 1.08;
  letter-spacing: -.025em;
}

body.bc-learning-page .topic-hero .topic-subtitle {
  margin: 0;
  color: var(--lesson-blue-gray);
  font-size: 15px;
}

body.bc-learning-page .section {
  margin-bottom: 18px;
  animation: none;
}

body.bc-learning-page .concept-card-wrapper {
  margin-bottom: 16px;
  overflow: hidden;
  border: 1px solid var(--lesson-rule) !important;
  border-radius: 4px;
  background: var(--lesson-sheet);
  box-shadow: none !important;
  animation: none;
}

body.bc-learning-page .concept-card-header {
  padding: 11px 15px;
  border-bottom: 1px solid var(--lesson-rule);
  background: #eef1ec !important;
}

body.bc-learning-page .concept-card-header h2 {
  margin: 0 !important;
  padding: 0 !important;
  border: 0 !important;
  font-size: 18px;
  line-height: 1.25;
}

body.bc-learning-page .concept-card-body {
  padding: 15px 17px 17px;
}

body.bc-learning-page .md-content {
  min-width: 0;
  color: #414a46 !important;
  font-size: 15px !important;
  line-height: 1.72 !important;
}

body.bc-learning-page .md-content h3 {
  margin: 20px 0 9px;
  color: var(--lesson-green);
  font-size: 16px;
}

body.bc-learning-page .md-content p,
body.bc-learning-page .md-content li {
  color: #414a46;
  font-size: 14.5px;
  line-height: 1.72;
}

body.bc-learning-page .md-content blockquote {
  margin: 16px 0;
  padding: 13px 15px;
  border: 1px solid #c9d1cc !important;
  border-left: 3px solid var(--lesson-green-2) !important;
  border-radius: 2px;
  background: #f2f4f0 !important;
  box-shadow: none !important;
}

body.bc-learning-page .formula-box,
body.bc-learning-page .worked-example,
body.bc-learning-page .practice-q-card,
body.bc-learning-page .exam-technique,
body.bc-learning-page .diagram-container,
body.bc-learning-page .diagram-figure {
  border-color: var(--lesson-rule) !important;
  border-radius: 3px !important;
  background: var(--lesson-sheet) !important;
  box-shadow: none !important;
}

body.bc-learning-page .formula-box {
  background: var(--lesson-blue-wash) !important;
}

body.bc-learning-page .mistake-card {
  border-color: #dbc2bd !important;
  border-left-color: var(--lesson-red) !important;
  border-radius: 3px !important;
  background: var(--lesson-red-wash) !important;
  box-shadow: none !important;
}

body.bc-learning-page .practice-q-card {
  margin-bottom: 14px;
  padding: 17px;
}

body.bc-learning-page .practice-opt-btn {
  min-height: 40px;
  padding: 9px 11px;
  border-radius: 3px !important;
  background: #faf9f4 !important;
  font-size: 13.5px;
}

body.bc-learning-page .practice-explanation {
  border-left-color: var(--lesson-green-2);
  border-radius: 2px;
  background: #edf2ef;
}

body.bc-learning-page :where(.md-content, .main-container, main) figure,
body.bc-learning-page :where(.calc-figure, .physics-figure, .diagram-panel, .visual-card, .figure-card, .image-card, .inline-fig, .fig-thumb, .example-visual, .diagram-card, .q-visual) {
  border-color: var(--lesson-rule-strong) !important;
  border-radius: 3px !important;
  background: var(--lesson-sheet) !important;
  box-shadow: none !important;
}

.lesson-sequence-nav {
  min-width: 0;
  display: grid;
  grid-template-columns: minmax(0, .8fr) minmax(260px, 1.4fr) minmax(0, .8fr);
  gap: 12px;
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--lesson-rule-strong);
}

.sequence-link {
  min-width: 0;
  display: grid;
  gap: 3px;
  padding: 11px 12px;
  border: 1px solid var(--lesson-rule-strong);
  border-radius: 3px;
  color: var(--lesson-ink);
  background: var(--lesson-sheet);
  text-decoration: none;
}

.sequence-link:hover {
  border-color: var(--lesson-green-2);
  color: var(--lesson-green);
}

.sequence-link span {
  color: var(--lesson-blue-gray);
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
}

.sequence-link strong {
  overflow: hidden;
  font-size: 12px;
  line-height: 1.35;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sequence-link small {
  color: var(--lesson-blue-gray);
  font-size: 10.5px;
  line-height: 1.4;
}

.topic-practice-link {
  border-color: var(--lesson-green-2);
  background: var(--lesson-green-wash);
  text-align: center;
}

.topic-practice-link strong {
  color: var(--lesson-green);
  font-family: var(--font-display);
  font-size: 16px;
  white-space: normal;
}

.sequence-link.next {
  text-align: right;
}

.lesson-coach {
  min-width: 0;
  height: 100%;
  overflow-x: hidden;
  overflow-y: auto;
  border-left: 1px solid var(--lesson-rule);
  background: #efeee7;
}

.coach-toggle {
  width: 100%;
  min-height: 54px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 13px 15px;
  border: 0;
  border-bottom: 1px solid var(--lesson-rule-strong);
  color: var(--lesson-green);
  background: var(--lesson-sheet);
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  text-align: left;
}

.coach-toggle svg {
  display: none;
}

.coach-body {
  display: grid;
  gap: 10px;
  padding: 12px;
}

.coach-section {
  min-width: 0;
  padding: 13px;
  border: 1px solid var(--lesson-rule);
  border-radius: 3px;
  background: var(--lesson-sheet);
}

.coach-section-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 9px;
}

.coach-section h2 {
  margin: 0;
  color: var(--lesson-ink);
  font-family: var(--font-body) !important;
  font-size: 12px;
  font-weight: 750;
}

.coach-section-heading > span {
  color: var(--lesson-blue-gray);
  font-size: 9.5px;
}

.coach-mastery-dots {
  margin-bottom: 7px;
}

.coach-mastery > strong {
  display: block;
  color: var(--lesson-green);
  font-size: 12.5px;
  line-height: 1.4;
}

.coach-section p,
.coach-section li {
  margin: 6px 0 0;
  color: #53605a;
  font-size: 11px;
  line-height: 1.48;
}

.coach-prerequisite-list {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.coach-prerequisite-list li {
  display: grid;
  grid-template-columns: 10px minmax(0, 1fr);
  align-items: start;
  gap: 8px;
  margin: 0;
}

.coach-prerequisite-list b,
.coach-prerequisite-list small {
  display: block;
}

.coach-prerequisite-list b {
  color: #3d4843;
  font-size: 10.5px;
  font-weight: 650;
}

.coach-prerequisite-list small {
  margin-top: 1px;
  color: var(--lesson-blue-gray);
  font-size: 9.5px;
}

.prerequisite-state {
  width: 8px;
  height: 8px;
  margin-top: 3px;
  border: 1px solid #aeb8b2;
  border-radius: 50%;
}

.prerequisite-state.secure {
  border-color: var(--lesson-green-2);
  background: var(--lesson-green-2);
}

.prerequisite-state.developing,
.prerequisite-state.fragile {
  border-color: #68848a;
  background: #68848a;
}

.prerequisite-state.support {
  border-color: var(--lesson-red);
  background: var(--lesson-red);
}

.coach-boundary {
  padding-top: 7px;
  border-top: 1px solid var(--lesson-rule);
  color: var(--lesson-blue-gray) !important;
  font-size: 9.5px !important;
}

.coach-budget-line {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 7px;
}

.coach-budget-line strong {
  color: var(--lesson-green);
  font: 700 15px/1 var(--font-mono);
}

.coach-budget-line span {
  color: var(--lesson-blue-gray);
  font-size: 9.5px;
}

.coach-mistake-book {
  border-left: 3px solid var(--lesson-red);
}

.coach-mistake-book .coach-section-heading > span {
  color: var(--lesson-red);
  font-weight: 700;
}

.coach-links {
  display: grid;
  gap: 6px;
  margin-top: 10px;
}

.coach-links a {
  padding-top: 6px;
  border-top: 1px solid var(--lesson-rule);
  color: var(--lesson-green);
  font-size: 10.5px;
  font-weight: 700;
  line-height: 1.35;
  text-decoration: none;
}

.coach-tutor {
  border-color: #b9c6ca;
  background: var(--lesson-blue-wash);
}

.coach-tutor > p {
  margin-bottom: 9px;
}

.coach-tutor > button {
  width: 100%;
  min-height: 36px;
  margin-top: 6px;
  padding: 7px 9px;
  border: 1px solid #899da5;
  border-radius: 3px;
  color: #344d59;
  background: var(--lesson-sheet);
  font-size: 10.5px;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
}

.coach-tutor > button:hover {
  color: var(--lesson-sheet);
  background: #516b78;
}

.coach-tutor > button:disabled {
  cursor: not-allowed;
  opacity: .45;
}

body.bc-learning-page #cbc-ai-fab {
  right: 320px !important;
  bottom: 18px !important;
  border-color: #516b78 !important;
  border-radius: 4px !important;
  color: var(--lesson-sheet) !important;
  background: #516b78 !important;
  box-shadow: 0 2px 7px rgba(35, 39, 37, .16) !important;
}

body.bc-learning-page #cbc-ai-panel {
  right: 318px !important;
  border-radius: 5px !important;
  box-shadow: 0 10px 30px rgba(35, 39, 37, .18) !important;
}

body.bc-learning-page .cbc-ai-head,
body.bc-learning-page .cbc-ai-send {
  background: #516b78 !important;
}

body.bc-learning-page .cbc-ai-status {
  border-color: #bac7cb !important;
  color: #344d59 !important;
  background: var(--lesson-blue-wash) !important;
}

body.bc-learning-page .cbc-ai-who {
  color: #516b78 !important;
}

@media (max-width: 1100px) {
  .lesson-app-header {
    grid-template-columns: auto minmax(0, 1fr) auto;
  }

  .lesson-primary-nav {
    justify-content: center;
  }

  .lesson-primary-nav a {
    padding: 0 8px;
  }

  .lesson-primary-nav a span {
    display: none;
  }

  .lesson-workspace {
    grid-template-columns: 248px minmax(0, 1fr);
  }

  body.bc-learning-page .content-wrapper {
    padding-bottom: 56px;
  }

  .lesson-coach {
    position: fixed;
    right: 0;
    bottom: 0;
    left: 248px;
    z-index: 230;
    width: auto;
    height: auto;
    overflow: visible;
    border-top: 1px solid var(--lesson-rule-strong);
    border-left: 0;
    background: var(--lesson-sheet);
  }

  .coach-toggle {
    min-height: 50px;
    padding: 10px 16px;
    border-bottom: 0;
    cursor: pointer;
  }

  .coach-toggle svg {
    display: block;
    transition: transform 160ms ease;
  }

  .lesson-coach[data-expanded="true"] .coach-toggle svg {
    transform: rotate(180deg);
  }

  .coach-body {
    max-height: 0;
    display: grid;
    grid-auto-flow: column;
    grid-auto-columns: minmax(218px, 1fr);
    gap: 10px;
    padding: 0 12px;
    overflow: hidden;
    border-top: 0 solid var(--lesson-rule);
    transition: max-height 180ms ease, padding 180ms ease, border-width 180ms ease;
  }

  .lesson-coach[data-expanded="true"] .coach-body {
    max-height: 56vh;
    padding: 12px;
    overflow-x: auto;
    overflow-y: hidden;
    border-top-width: 1px;
  }

  .coach-section {
    overflow-y: auto;
  }

  body.bc-learning-page #cbc-ai-fab {
    right: 15px !important;
    bottom: 66px !important;
  }

  body.bc-learning-page #cbc-ai-panel {
    right: 12px !important;
    bottom: 64px !important;
  }

  body.bc-learning-page.lesson-coach-open #cbc-ai-fab {
    display: none !important;
  }
}

@media (max-width: 900px) {
  body.bc-learning-page {
    display: block !important;
    height: 100vh;
  }

  .lesson-app-header {
    height: 56px;
    padding: 0 14px;
  }

  .lesson-brand {
    font-size: 18px;
  }

  .lesson-brand-mark {
    width: 31px;
    height: 31px;
    font-size: 20px;
  }

  .lesson-study-record {
    display: none;
  }

  .lesson-workspace {
    height: calc(100vh - 56px);
    display: block;
  }

  body.bc-learning-page .sidebar {
    position: fixed;
    inset: 56px auto 0 0;
    z-index: 520;
    width: min(86vw, 324px);
    height: auto;
    transform: translateX(-105%);
    transition: transform 180ms ease;
    box-shadow: 12px 0 24px rgba(35, 39, 37, .12);
  }

  body.sidebar-open .sidebar {
    transform: translateX(0);
  }

  .sidebar-close {
    display: grid;
  }

  body.sidebar-open .sidebar-backdrop {
    position: fixed;
    inset: 56px 0 0;
    z-index: 510;
    display: block;
    background: rgba(35, 39, 37, .28);
    backdrop-filter: none;
  }

  body.bc-learning-page .content-wrapper {
    width: 100%;
    height: 100%;
    padding-bottom: 56px;
  }

  body.bc-learning-page .top-bar {
    min-height: 52px !important;
    height: 52px !important;
    flex-basis: 52px;
    padding: 0 12px !important;
  }

  .mobile-menu-btn {
    display: inline-grid;
    place-items: center;
  }

  .lesson-reading-state {
    top: 52px;
    padding: 7px 12px;
  }

  .lesson-coach {
    left: 0;
  }

  .lesson-coach[data-expanded="true"] .coach-body {
    max-height: 62vh;
    grid-auto-flow: row;
    grid-template-columns: 1fr;
    overflow-x: hidden;
    overflow-y: auto;
  }

  .coach-section {
    overflow: visible;
  }
}

@media (max-width: 620px) {
  .lesson-app-header {
    height: 52px;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 8px;
    padding: 0 10px;
  }

  .lesson-brand {
    overflow: hidden;
    font-size: 16px;
    white-space: nowrap;
  }

  .lesson-brand-mark {
    width: 29px;
    height: 29px;
    flex: 0 0 29px;
    font-size: 18px;
  }

  .lesson-primary-nav {
    height: 100%;
  }

  .lesson-primary-nav a {
    display: none;
  }

  .lesson-primary-nav a.active {
    display: inline-flex;
    padding: 0 10px;
    font-size: 12px;
  }

  .lesson-workspace {
    height: calc(100vh - 52px);
  }

  body.bc-learning-page .sidebar,
  body.sidebar-open .sidebar-backdrop {
    top: 52px;
  }

  body.bc-learning-page .module-title span,
  body.bc-learning-page .lesson-reference-link {
    display: none !important;
  }

  body.bc-learning-page .module-title {
    font-size: 11px !important;
  }

  body.bc-learning-page .lang-btn {
    min-height: 30px;
    padding: 3px 8px;
    font-size: 10.5px;
  }

  .lesson-reading-state {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 6px 8px;
  }

  .lesson-reading-state progress {
    grid-column: 1 / -1;
    grid-row: 2;
  }

  .lesson-reading-state small {
    display: none;
  }

  #lesson-mark-read {
    min-height: 30px;
    padding: 4px 7px;
    font-size: 9.5px;
  }

  body.bc-learning-page .main-container {
    max-width: none !important;
    padding: 18px 12px 112px !important;
  }

  body.bc-learning-page .topic-hero h1 {
    font-size: 27px;
  }

  body.bc-learning-page .concept-card-header,
  body.bc-learning-page .concept-card-body,
  body.bc-learning-page .practice-q-card {
    padding-right: 12px;
    padding-left: 12px;
  }

  body.bc-learning-page .md-content,
  body.bc-learning-page .md-content p,
  body.bc-learning-page .md-content li {
    font-size: 14px !important;
  }

  body.bc-learning-page .table-scroll,
  body.bc-learning-page .concept-card-body {
    max-width: 100%;
  }

  .lesson-sequence-nav {
    grid-template-columns: minmax(0, 1fr);
    gap: 7px;
  }

  .lesson-sequence-nav > span:empty {
    display: none;
  }

  .sequence-link.previous,
  .sequence-link.next {
    text-align: left;
  }

  .sequence-link {
    padding: 9px;
  }

  .sequence-link strong {
    white-space: normal;
  }

  body.bc-learning-page #cbc-ai-fab {
    right: 10px !important;
    bottom: 64px !important;
  }

  body.bc-learning-page #cbc-ai-panel {
    right: 7px !important;
    bottom: 60px !important;
    width: calc(100vw - 14px) !important;
    height: calc(100vh - 72px) !important;
  }
}

@media print {
  .lesson-app-header,
  .sidebar,
  .lesson-coach,
  .lesson-reading-state,
  .lesson-sequence-nav,
  .top-bar {
    display: none !important;
  }

  html,
  body.bc-learning-page,
  .lesson-workspace,
  body.bc-learning-page .content-wrapper {
    height: auto;
    overflow: visible !important;
    background: #fff !important;
  }

  .lesson-workspace {
    display: block;
  }
}