* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-width: 320px;
  min-height: 100%;
  background: var(--surface-canvas);
  color: var(--text-primary);
  font-family: var(--font-ui);
}

body {
  overflow: hidden;
}

button,
a {
  font: inherit;
}

button {
  color: inherit;
}

.app-shell {
  height: 100dvh;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  background: var(--surface-canvas);
}

.app-shell__topbar {
  min-height: 64px;
  display: grid;
  grid-template-areas: "brand context status";
  grid-template-columns: minmax(180px, 0.8fr) minmax(320px, 2fr) minmax(160px, 0.8fr);
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-5);
  border-bottom: 1px solid var(--divider-default);
  background: var(--surface-base);
  z-index: 3;
}

.brand {
  grid-area: brand;
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  width: max-content;
  color: var(--text-primary);
  text-decoration: none;
  font-weight: var(--weight-bold);
  letter-spacing: -0.02em;
}

.brand__mark {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-md);
  background: var(--mode-accent);
  color: var(--mode-accent-text);
  font-family: var(--font-math);
  font-size: var(--text-xl);
  line-height: 1;
}

.brand__text {
  font-size: var(--text-md);
}

.topic-navigation-toggle {
  grid-area: nav-toggle;
  display: none;
  min-height: var(--touch-target-min);
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.topic-navigation-toggle__icon {
  width: 18px;
  display: grid;
  gap: 3px;
}

.topic-navigation-toggle__icon span {
  height: 2px;
  border-radius: var(--radius-pill);
  background: currentColor;
}

.topbar__context,
.topbar__status {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-width: 0;
}

.topbar__context {
  grid-area: context;
  justify-content: center;
}

.breadcrumb {
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.scope-badge {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 var(--space-3);
  border: 1px solid var(--scope-border);
  border-radius: var(--radius-pill);
  background: var(--scope-background);
  color: var(--scope-text);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.scope-badge--compact {
  min-height: 24px;
  padding: 0 var(--space-2);
  font-size: 0.64rem;
  letter-spacing: 0.025em;
}

.topbar__status {
  grid-area: status;
  justify-content: flex-end;
  color: var(--text-muted);
  font-size: var(--text-sm);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--feedback-info-accent);
}

.app-shell__body {
  position: relative;
  min-height: 0;
  display: grid;
  grid-template-columns: 248px minmax(0, 1fr);
  gap: var(--space-4);
  padding: var(--space-4);
  overflow: hidden;
}

.navigation-scrim {
  display: none;
}

.topic-navigation {
  min-height: 0;
  overflow: auto;
  padding: var(--space-4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-raised);
}

.topic-navigation__heading-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
}

.topic-navigation__heading {
  display: grid;
  gap: var(--space-1);
  margin-bottom: var(--space-4);
}

.topic-navigation__close {
  display: none;
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  flex: 0 0 auto;
  place-items: center;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-xl);
  line-height: 1;
  cursor: pointer;
}

.eyebrow,
.activity-overline,
.activity-callout__label {
  margin: 0;
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.topic-navigation__course {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
}

.topic-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: var(--space-2);
}

.topic-link {
  width: 100%;
  min-height: var(--touch-target-min);
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr) 22px;
  gap: var(--space-2);
  align-items: start;
  padding: var(--space-2) var(--space-2);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  background: transparent;
  text-align: left;
  cursor: pointer;
}

.topic-link__body {
  min-width: 0;
  display: grid;
  gap: 5px;
}

.topic-link__title {
  min-width: 0;
  line-height: var(--leading-tight);
}

.topic-mode-progress {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  min-height: 18px;
}

.mode-progress-marker {
  min-width: 22px;
  height: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
  padding: 0 2px;
  border: 1px solid var(--progress-not-started);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-muted);
  font-size: 0.58rem;
  font-weight: var(--weight-bold);
  line-height: 1;
}

.mode-progress-marker[data-progress-state="partial"] {
  border-color: var(--progress-in-progress);
  box-shadow: inset 0 -3px 0 var(--progress-in-progress);
  color: var(--text-primary);
}

.mode-progress-marker[data-progress-state="complete"] {
  border-color: var(--progress-complete);
  background: var(--progress-complete);
  color: var(--surface-base);
}

.topic-state-marker {
  width: 22px;
  height: 22px;
  display: inline-grid;
  place-items: center;
  align-self: center;
  border: 1px solid var(--progress-not-started);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-muted);
  font-size: 0.72rem;
  font-weight: var(--weight-bold);
  line-height: 1;
}

.topic-state-marker[data-progress-state="partial"] {
  border-color: var(--progress-in-progress);
  box-shadow: inset 0 -6px 0 var(--progress-in-progress);
  color: var(--text-primary);
}

.topic-state-marker[data-progress-state="complete"] {
  border-color: var(--progress-complete);
  background: var(--progress-complete);
  color: var(--surface-base);
}

.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

.topic-link:hover {
  background: var(--surface-subtle);
}

.topic-link.is-current {
  border-color: var(--border-default);
  background: var(--mode-soft);
  color: var(--mode-soft-text);
  font-weight: var(--weight-semibold);
}

.topic-index {
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
}

.topic-navigation__section {
  display: grid;
  gap: var(--space-2);
}

.topic-navigation__section + .topic-navigation__section {
  margin-top: var(--space-4);
}

.topic-navigation__section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: 0 var(--space-1);
}

.topic-navigation__section-label {
  color: var(--text-secondary);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.topic-list--secondary .topic-link {
  color: var(--text-secondary);
}

.topic-link--review {
  border-color: var(--scope-border);
  background: var(--scope-background);
  color: var(--scope-text);
  font-weight: var(--weight-semibold);
}

.topic-link--review:hover {
  background: var(--scope-background);
}

.topic-navigation__checkpoint {
  display: grid;
  grid-template-columns: minmax(10px, 1fr) minmax(0, auto) minmax(10px, 1fr);
  gap: var(--space-2);
  align-items: center;
  margin: var(--space-4) 0;
}

.checkpoint-rule {
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--progress-complete);
}

.checkpoint-copy {
  display: grid;
  gap: 2px;
  max-width: 150px;
  color: var(--text-secondary);
  text-align: center;
}

.checkpoint-copy strong {
  color: var(--text-primary);
  font-size: 0.67rem;
  letter-spacing: 0.045em;
  line-height: var(--leading-tight);
  text-transform: uppercase;
}

.checkpoint-copy span {
  color: var(--text-muted);
  font-size: 0.63rem;
  line-height: var(--leading-tight);
}

.topic-navigation__full-course {
  display: grid;
  gap: var(--space-2);
  margin-top: var(--space-4);
  padding: var(--space-3);
  border: 1px solid var(--scope-border);
  border-radius: var(--radius-md);
  background: var(--scope-background);
  color: var(--scope-text);
}

.topic-navigation__full-course-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
}

.topic-navigation__full-course > .scope-badge,
.topic-navigation__full-course-heading > .scope-badge {
  justify-self: start;
}

.topic-mode-progress--full {
  margin-top: var(--space-2);
}

.topic-navigation__full-course > div {
  display: grid;
  gap: 2px;
}

.topic-navigation__full-course strong {
  font-size: var(--text-sm);
}

.topic-navigation__full-course div span {
  color: var(--text-secondary);
  font-size: var(--text-xs);
  line-height: var(--leading-normal);
}

.learning-workspace {
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-raised);
  overflow: hidden;
}

.workspace-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--divider-default);
}

.workspace-header h1 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-xl);
  line-height: var(--leading-tight);
  letter-spacing: -0.025em;
}

.mode-tabs {
  width: min(100%, 570px);
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: var(--space-1);
  padding: var(--space-1);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-subtle);
}

.mode-tab {
  min-width: 0;
  min-height: var(--touch-target-min);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition:
    background-color var(--motion-fast) var(--motion-easing),
    border-color var(--motion-fast) var(--motion-easing),
    color var(--motion-fast) var(--motion-easing),
    box-shadow var(--motion-fast) var(--motion-easing);
}

.mode-tab:hover {
  background: var(--mode-soft);
  color: var(--mode-soft-text);
}

.mode-tab[aria-selected="true"] {
  border-color: var(--mode-accent);
  background: var(--mode-soft);
  color: var(--mode-soft-text);
  box-shadow: inset 0 -3px 0 var(--mode-accent);
}

.mode-tab__icon {
  width: 20px;
  height: 20px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  color: var(--mode-accent);
}

.mode-tab__icon svg {
  width: 100%;
  height: 100%;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.mode-tab__text {
  min-width: 0;
  display: grid;
  gap: 1px;
  line-height: 1.05;
  text-align: left;
}

.mode-tab__label {
  color: currentColor;
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  white-space: nowrap;
}

.mode-tab__sublabel {
  color: var(--text-muted);
  font-size: 0.64rem;
  font-weight: var(--weight-medium);
  white-space: nowrap;
}

.mode-tab[aria-selected="true"] .mode-tab__sublabel {
  color: var(--mode-soft-text);
}


.activity-stage__tools {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.activity-help-button {
  min-height: var(--touch-target-min);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.activity-help-button:hover {
  border-color: var(--mode-accent);
  background: var(--mode-soft);
  color: var(--mode-soft-text);
}

.activity-help-button__icon {
  width: 20px;
  height: 20px;
  display: inline-grid;
  place-items: center;
  border-radius: var(--radius-pill);
  background: var(--surface-subtle);
  color: var(--text-primary);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
}

.help-drawer-scrim {
  position: absolute;
  inset: 0;
  z-index: 40;
  width: 100%;
  height: 100%;
  border: 0;
  background: var(--overlay-scrim);
  opacity: 0.72;
  cursor: pointer;
}

.help-drawer-scrim:not([hidden]) {
  display: block;
}

.help-drawer {
  position: absolute;
  inset: 0 0 0 auto;
  z-index: 50;
  width: min(388px, calc(100% - 56px));
  min-width: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  border-left: 1px solid var(--border-default);
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-drawer);
  transform: translateX(calc(100% + var(--space-4)));
  visibility: hidden;
  transition:
    transform var(--motion-normal) var(--motion-easing),
    visibility 0s linear var(--motion-normal);
}

.app-shell[data-help-open="true"] .help-drawer {
  transform: translateX(0);
  visibility: visible;
  transition-delay: 0s;
}

.help-drawer__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--divider-default);
}

.help-drawer__header .eyebrow {
  margin: 0;
}

.help-drawer__header h2 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-xl);
  letter-spacing: -0.025em;
}

.help-drawer__close {
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--surface-subtle);
  color: var(--text-secondary);
  font-size: var(--text-xl);
  line-height: 1;
  cursor: pointer;
}

.help-drawer__close:hover {
  border-color: var(--border-default);
  background: var(--surface-base);
  color: var(--text-primary);
}

.help-drawer__body {
  min-height: 0;
  overflow: auto;
  padding: var(--space-5);
  overscroll-behavior: contain;
}

.help-drawer__context {
  margin: 0 0 var(--space-4);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}

.help-drawer__targets {
  display: grid;
  gap: var(--space-2);
}

.help-target {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: var(--space-3);
  min-height: 76px;
  padding: var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-primary);
  text-decoration: none;
}

.help-target:hover,
.help-target:focus-visible {
  border-color: var(--mode-accent);
  background: var(--mode-soft);
}

.help-target__badge {
  min-width: 76px;
  min-height: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 var(--space-2);
  border: 1px solid var(--mode-accent);
  border-radius: var(--radius-pill);
  background: var(--mode-soft);
  color: var(--mode-soft-text);
  font-size: 0.7rem;
  font-weight: var(--weight-bold);
  letter-spacing: 0.035em;
  text-transform: uppercase;
}

.help-target__content {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.help-target__content strong {
  font-size: var(--text-sm);
  line-height: var(--leading-tight);
}

.help-target__description {
  color: var(--text-secondary);
  font-size: var(--text-xs);
  line-height: var(--leading-normal);
}

.help-target__arrow {
  color: var(--mode-soft-text);
  font-size: var(--text-lg);
  line-height: 1;
}

.help-drawer__return-note {
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: 1px solid var(--divider-default);
  color: var(--text-muted);
  font-size: var(--text-xs);
  line-height: var(--leading-normal);
}


.word-bank-button {
  min-height: var(--touch-target-min);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.word-bank-button:hover {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
}

.word-bank-button__icon {
  color: var(--feedback-info-ink);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
}

.word-bank-button__count {
  min-width: 22px;
  height: 22px;
  display: inline-grid;
  place-items: center;
  padding: 0 5px;
  border-radius: var(--radius-pill);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
  font-size: 0.68rem;
  font-weight: var(--weight-bold);
  font-variant-numeric: tabular-nums;
}

.vocabulary-term-wrap {
  position: relative;
  display: inline;
}

.vocabulary-term {
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
  margin: 0 1px;
  padding: 1px 4px;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: inherit;
  font: inherit;
  line-height: inherit;
  cursor: pointer;
}

.vocabulary-term--new {
  padding-left: 1px;
  padding-right: 1px;
  border-bottom: 1px dotted var(--feedback-info-accent);
  border-radius: 0;
  color: var(--text-primary);
  font-weight: var(--weight-semibold);
}

.vocabulary-term--known {
  border-radius: var(--radius-pill);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
}

.vocabulary-new-marker {
  display: inline-flex;
  align-items: center;
  min-height: 16px;
  padding: 0 4px;
  border-radius: var(--radius-pill);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
  font-size: 0.56rem;
  font-weight: var(--weight-bold);
  letter-spacing: 0.06em;
}

.vocabulary-popover {
  position: absolute;
  left: 0;
  top: calc(100% + var(--space-2));
  z-index: 60;
  width: min(320px, calc(100vw - 40px));
  display: grid;
  gap: var(--space-2);
  padding: var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-raised);
  box-shadow: var(--shadow-raised);
  color: var(--text-primary);
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  transform: translateY(4px);
  transition:
    opacity var(--motion-fast) var(--motion-easing),
    transform var(--motion-fast) var(--motion-easing),
    visibility 0s linear var(--motion-fast);
}

.vocabulary-term-wrap:hover .vocabulary-popover,
.vocabulary-term-wrap:focus-within .vocabulary-popover,
.vocabulary-term-wrap[data-popover-open="true"] .vocabulary-popover {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
  transition-delay: 0s;
}

.vocabulary-popover__term {
  font-size: var(--text-sm);
}

.vocabulary-popover__definition {
  color: var(--text-secondary);
}

.vocabulary-popover__open-bank {
  justify-self: start;
  min-height: var(--touch-target-min);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--feedback-info-ink);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.app-shell[data-help-open="true"] .vocabulary-popover,
.app-shell[data-word-bank-open="true"] .vocabulary-popover {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.word-bank-drawer-scrim {
  position: absolute;
  inset: 0;
  z-index: 40;
  width: 100%;
  height: 100%;
  border: 0;
  background: var(--overlay-scrim);
  opacity: 0.72;
  cursor: pointer;
}

.word-bank-drawer-scrim:not([hidden]) {
  display: block;
}

.word-bank-drawer {
  position: absolute;
  inset: 0 0 0 auto;
  z-index: 50;
  width: min(520px, calc(100% - 56px));
  min-width: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  border-left: 1px solid var(--border-default);
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-drawer);
  transform: translateX(calc(100% + var(--space-4)));
  visibility: hidden;
  transition:
    transform var(--motion-normal) var(--motion-easing),
    visibility 0s linear var(--motion-normal);
}

.app-shell[data-word-bank-open="true"] .word-bank-drawer {
  transform: translateX(0);
  visibility: visible;
  transition-delay: 0s;
}

.word-bank-drawer__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--divider-default);
}

.word-bank-drawer__header h2 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-xl);
  letter-spacing: -0.025em;
}

.word-bank-drawer__close {
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--surface-subtle);
  color: var(--text-secondary);
  font-size: var(--text-xl);
  line-height: 1;
  cursor: pointer;
}

.word-bank-drawer__close:hover {
  border-color: var(--border-default);
  background: var(--surface-base);
  color: var(--text-primary);
}

.word-bank-drawer__body {
  min-height: 0;
  overflow: auto;
  padding: var(--space-5);
  overscroll-behavior: contain;
}

.word-bank-search {
  display: grid;
  gap: var(--space-2);
}

.word-bank-search label {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
}

.word-bank-search input {
  width: 100%;
  min-height: var(--control-height);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-primary);
}

.word-bank-filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.word-bank-filter {
  min-height: var(--touch-target-min);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.word-bank-filter.is-active,
.word-bank-filter[aria-pressed="true"] {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
}

.word-bank-results-summary {
  margin: var(--space-3) 0;
  color: var(--text-muted);
  font-size: var(--text-xs);
}

.word-bank-content,
.word-bank-list {
  display: grid;
  gap: var(--space-2);
}

.word-bank-content {
  gap: var(--space-4);
}

.word-bank-entry {
  width: 100%;
  min-height: var(--touch-target-min);
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: var(--space-2);
  align-items: center;
  padding: var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-primary);
  text-align: left;
  cursor: pointer;
}

.word-bank-entry:hover,
.word-bank-entry.is-selected {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-soft);
}

.word-bank-entry__copy {
  min-width: 0;
  display: grid;
  gap: 2px;
}

.word-bank-entry__copy strong {
  font-size: var(--text-sm);
}

.word-bank-entry__definition {
  overflow: hidden;
  color: var(--text-secondary);
  font-size: var(--text-xs);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.word-bank-entry__meta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  color: var(--text-muted);
  font-size: 0.68rem;
  white-space: nowrap;
}

.word-bank-entry__review {
  color: var(--feedback-warning-ink);
  font-weight: var(--weight-bold);
}

.word-bank-empty {
  margin: 0;
  padding: var(--space-4);
  border: 1px dashed var(--border-default);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  text-align: center;
}

.word-bank-detail {
  padding: var(--space-4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-subtle);
}

.word-bank-detail__heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
}

.word-bank-detail__scope {
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.word-bank-detail h3 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-lg);
}

.word-bank-review-toggle {
  min-height: var(--touch-target-min);
  flex: 0 0 auto;
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.word-bank-review-toggle[aria-pressed="true"] {
  border-color: var(--feedback-warning-accent);
  background: var(--feedback-warning-soft);
  color: var(--feedback-warning-ink);
}

.word-bank-detail__grid {
  display: grid;
  gap: var(--space-3);
  margin: var(--space-4) 0 0;
}

.word-bank-detail__grid > div {
  display: grid;
  gap: 3px;
}

.word-bank-detail dt {
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  text-transform: uppercase;
}

.word-bank-detail dd {
  margin: 0;
  color: var(--text-secondary);
  line-height: var(--leading-normal);
}

.word-bank-detail__notation {
  font-family: var(--font-math);
  color: var(--text-primary) !important;
}

.word-bank-drawer__note {
  margin: var(--space-5) 0 0;
  padding-top: var(--space-4);
  border-top: 1px solid var(--divider-default);
  color: var(--text-muted);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}

.activity-frame {
  min-height: 0;
  padding: var(--space-4);
  background: var(--surface-canvas);
  overflow: hidden;
}

.activity-stage {
  height: 100%;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  gap: var(--space-4);
  padding: var(--space-5);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-base);
  overflow: auto;
  overscroll-behavior: contain;
}

.activity-stage__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.activity-chip {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 var(--space-3);
  border-radius: var(--radius-pill);
  background: var(--mode-soft);
  color: var(--mode-soft-text);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
}

.activity-position {
  color: var(--text-muted);
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
}

.activity-stage__content {
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(260px, 0.8fr) minmax(380px, 1.2fr);
  gap: clamp(var(--space-5), 4vw, var(--space-7));
  align-items: center;
}

.activity-copy {
  max-width: 560px;
}

.activity-copy h2 {
  margin: var(--space-2) 0 var(--space-4);
  font-size: clamp(1.75rem, 3vw, 2.65rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.activity-copy > p:not(.activity-overline) {
  margin: 0;
  color: var(--text-secondary);
  font-size: var(--text-md);
  line-height: var(--leading-relaxed);
}

.activity-callout {
  margin-top: var(--space-5);
  padding: var(--space-4);
  border-left: 4px solid var(--mode-accent);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  background: var(--mode-soft);
  color: var(--mode-soft-text);
}

.activity-callout p {
  margin: var(--space-2) 0 0;
  line-height: var(--leading-normal);
}

.math-placeholder {
  position: relative;
  min-height: 330px;
  height: min(46vh, 470px);
  display: grid;
  place-items: center;
  align-content: center;
  gap: var(--space-3);
  overflow: hidden;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  background: var(--surface-base);
}

.math-placeholder__grid {
  position: absolute;
  inset: 0;
  opacity: 0.6;
  background-image:
    linear-gradient(to right, var(--divider-default) 1px, transparent 1px),
    linear-gradient(to bottom, var(--divider-default) 1px, transparent 1px);
  background-size: 36px 36px;
  mask-image: linear-gradient(to bottom, transparent 0%, black 15%, black 85%, transparent 100%);
}

.math-placeholder__formula,
.math-placeholder__caption {
  position: relative;
  z-index: 1;
}

.math-placeholder__formula {
  padding: var(--space-3) var(--space-5);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-raised);
  font-family: var(--font-math);
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 1.15;
}

.math-placeholder__caption {
  max-width: 420px;
  margin: 0;
  padding: 0 var(--space-4);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
  text-align: center;
}

.activity-controls {
  min-height: 72px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-5);
  border-top: 1px solid var(--divider-default);
  background: var(--surface-base);
}

.activity-button {
  min-height: var(--touch-target-min);
  min-width: 124px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0 var(--space-4);
  border-radius: var(--radius-md);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.activity-button--secondary {
  justify-self: start;
  border: 1px solid var(--border-default);
  background: var(--surface-base);
}

.activity-button--primary {
  justify-self: end;
  border: 1px solid var(--mode-accent);
  background: var(--mode-accent);
  color: var(--mode-accent-text);
}

.activity-controls__summary {
  display: grid;
  gap: var(--space-1);
  text-align: center;
}

.activity-controls__summary strong {
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
}

/* Compact desktop / landscape tablet: retain the two-column shell but reduce chrome. */
@media (max-width: 1100px) and (min-width: 901px) {
  .app-shell__topbar {
    grid-template-columns: minmax(150px, 0.7fr) minmax(300px, 1.8fr) minmax(130px, 0.6fr);
    padding-left: var(--space-4);
    padding-right: var(--space-4);
  }

  .app-shell__body {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: var(--space-3);
    padding: var(--space-3);
  }

  .workspace-header {
    gap: var(--space-3);
    padding-left: var(--space-4);
    padding-right: var(--space-4);
  }

  .workspace-header h1 {
    font-size: var(--text-lg);
  }

  .mode-tabs {
    width: min(100%, 470px);
  }

  .mode-tab {
    gap: var(--space-1);
    padding-left: var(--space-1);
    padding-right: var(--space-1);
  }

  .mode-tab__icon {
    width: 18px;
    height: 18px;
  }

  .mode-tab__sublabel {
    display: none;
  }

  .activity-stage {
    padding: var(--space-4);
  }

  .activity-stage__content {
    grid-template-columns: minmax(230px, 0.8fr) minmax(300px, 1.2fr);
    gap: var(--space-5);
  }

  .activity-copy h2 {
    font-size: clamp(1.65rem, 3vw, 2.2rem);
  }

  .math-placeholder {
    min-height: 300px;
  }
}

/* Tablet / compact shell: topic navigation becomes one shared overlay drawer. */
@media (max-width: 900px) {
  .app-shell__topbar {
    grid-template-areas: "brand nav-toggle context";
    grid-template-columns: auto auto minmax(0, 1fr);
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
  }

  .topic-navigation-toggle {
    display: inline-flex;
  }

  .topbar__context {
    justify-content: flex-end;
  }

  .topbar__status {
    display: none;
  }

  .app-shell__body {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    padding: var(--space-3);
  }

  .navigation-scrim {
    position: fixed;
    inset: 0;
    z-index: 20;
    width: 100%;
    height: 100%;
    border: 0;
    background: var(--overlay-scrim);
    cursor: pointer;
  }

  .navigation-scrim:not([hidden]) {
    display: block;
  }

  .topic-navigation {
    position: fixed;
    inset: 0 auto 0 0;
    z-index: 30;
    width: min(320px, calc(100vw - 48px));
    max-width: 100%;
    padding: var(--space-5) var(--space-4);
    border: 0;
    border-right: 1px solid var(--border-default);
    border-radius: 0 var(--radius-lg) var(--radius-lg) 0;
    box-shadow: var(--shadow-drawer);
    transform: translateX(calc(-100% - var(--space-4)));
    visibility: hidden;
    transition:
      transform var(--motion-normal) var(--motion-easing),
      visibility 0s linear var(--motion-normal);
  }

  .app-shell[data-navigation-open="true"] .topic-navigation {
    transform: translateX(0);
    visibility: visible;
    transition-delay: 0s;
  }

  .topic-navigation__close {
    display: grid;
  }

  .learning-workspace {
    height: 100%;
  }

  .workspace-header,
  .activity-stage {
    padding-left: var(--space-4);
    padding-right: var(--space-4);
  }

  .workspace-header {
    gap: var(--space-3);
  }

  .workspace-header h1 {
    font-size: var(--text-lg);
  }

  .mode-tabs {
    width: min(100%, 500px);
  }

  .mode-tab {
    gap: var(--space-1);
    padding-left: var(--space-2);
    padding-right: var(--space-2);
  }

  .mode-tab__sublabel {
    display: none;
  }

  .activity-stage__content {
    grid-template-columns: minmax(210px, 0.8fr) minmax(300px, 1.2fr);
    gap: var(--space-5);
  }

  .activity-copy h2 {
    font-size: clamp(1.55rem, 3vw, 2.1rem);
  }

  .activity-copy > p:not(.activity-overline) {
    font-size: var(--text-base);
  }

  .math-placeholder {
    min-height: 280px;
    height: min(42vh, 420px);
  }
}

/* Narrow screen: keep the shell fixed; stack only the activity and let that panel scroll. */
@media (max-width: 680px) {
  .app-shell__topbar {
    grid-template-areas:
      "brand nav-toggle"
      "context context";
    grid-template-columns: minmax(0, 1fr) auto;
    row-gap: var(--space-2);
    padding: var(--space-2) var(--space-3) var(--space-3);
  }

  .brand {
    gap: var(--space-2);
  }

  .brand__mark {
    width: 34px;
    height: 34px;
  }

  .topic-navigation-toggle {
    justify-self: end;
    min-height: var(--touch-target-min);
  }

  .topbar__context {
    justify-content: space-between;
    gap: var(--space-2);
  }

  .breadcrumb {
    font-size: var(--text-sm);
  }

  .scope-badge {
    min-height: 28px;
    padding-left: var(--space-2);
    padding-right: var(--space-2);
    font-size: 0.68rem;
  }

  .app-shell__body {
    padding: var(--space-2);
  }

  .topic-navigation {
    width: min(304px, calc(100vw - 32px));
  }

  .learning-workspace {
    border-radius: var(--radius-md);
  }

  .workspace-header {
    align-items: stretch;
    flex-direction: column;
    gap: var(--space-2);
    padding: var(--space-3);
  }

  .workspace-header h1 {
    margin-top: 2px;
    font-size: var(--text-md);
  }

  .mode-tabs {
    width: 100%;
    max-width: none;
    gap: 3px;
    padding: 3px;
  }

  .mode-tab {
    min-height: 46px;
    flex-direction: column;
    gap: 2px;
    padding: var(--space-1) 2px;
  }

  .mode-tab__icon {
    width: 17px;
    height: 17px;
  }

  .mode-tab__text {
    display: block;
    text-align: center;
  }

  .mode-tab__label {
    font-size: 0.62rem;
    letter-spacing: -0.01em;
  }

  .mode-tab__sublabel {
    display: none;
  }

  .activity-frame {
    padding: var(--space-2);
  }

  .activity-stage {
    gap: var(--space-3);
    padding: var(--space-3);
  }

  .activity-stage__header {
    align-items: flex-start;
  }

  .activity-stage__tools {
    gap: var(--space-2);
  }

  .activity-help-button {
    min-height: var(--touch-target-min);
    padding: 0 var(--space-2);
    font-size: var(--text-xs);
  }

  .activity-help-button__icon {
    display: none;
  }

  .help-drawer {
    width: min(392px, calc(100% - var(--space-3)));
    border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  }

  .help-drawer__header,
  .help-drawer__body {
    padding: var(--space-4);
  }

  .activity-stage__content {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-5);
    align-content: start;
  }

  .activity-copy {
    max-width: none;
  }

  .activity-copy h2 {
    margin-bottom: var(--space-3);
    font-size: clamp(1.55rem, 7vw, 2rem);
  }

  .activity-copy > p:not(.activity-overline) {
    font-size: var(--text-base);
    line-height: var(--leading-normal);
  }

  .activity-callout {
    margin-top: var(--space-4);
    padding: var(--space-3);
  }

  .math-placeholder {
    min-height: 280px;
    height: auto;
    padding: var(--space-7) var(--space-3);
  }

  .math-placeholder__formula {
    max-width: 100%;
    overflow-wrap: anywhere;
    padding-left: var(--space-3);
    padding-right: var(--space-3);
    font-size: clamp(2rem, 12vw, 3.25rem);
    text-align: center;
  }

  .activity-controls {
    min-height: 62px;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    gap: var(--space-2);
    padding: var(--space-2) var(--space-3);
  }

  .activity-button {
    min-width: 0;
    width: 100%;
    padding: 0 var(--space-2);
  }

  .activity-controls__summary .eyebrow {
    display: none;
  }

  .activity-controls__summary strong {
    white-space: nowrap;
  }
}



@media (max-width: 680px) {
  .word-bank-button {
    min-height: var(--touch-target-min);
    padding: 0 var(--space-2);
  }

  .word-bank-button__label {
    display: none;
  }

  .word-bank-drawer {
    width: min(100%, 460px);
    border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  }

  .word-bank-drawer__header,
  .word-bank-drawer__body {
    padding: var(--space-4);
  }

  .word-bank-detail__heading {
    align-items: stretch;
    flex-direction: column;
  }

  .word-bank-review-toggle {
    align-self: flex-start;
  }

  .vocabulary-popover {
    width: min(280px, calc(100vw - 32px));
  }
}

@media (max-width: 380px) {
  .mode-tab__label {
    font-size: 0.56rem;
  }
}

@media (max-height: 660px) and (min-width: 681px) {
  .workspace-header {
    padding-top: var(--space-2);
    padding-bottom: var(--space-2);
  }

  .activity-frame {
    padding-top: var(--space-2);
    padding-bottom: var(--space-2);
  }

  .activity-stage {
    padding-top: var(--space-3);
    padding-bottom: var(--space-3);
  }

  .math-placeholder {
    min-height: 240px;
    height: 34vh;
  }
}

@media (prefers-reduced-motion: reduce) {
  .topic-navigation,
  .help-drawer,
  .word-bank-drawer,
  .vocabulary-popover {
    transition: none;
  }
}

/* Step 14: versioned local progress/security data controls */
.topic-navigation__actions {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.data-management-trigger,
.data-management-dialog__close,
.data-management-button {
  min-height: var(--touch-target-min);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.data-management-trigger {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 0 var(--space-2);
  min-height: var(--touch-target-min);
  font-size: var(--text-xs);
}

.data-management-trigger:hover,
.data-management-button--secondary:hover,
.data-management-dialog__close:hover {
  background: var(--surface-subtle);
  color: var(--text-primary);
}

.data-management-dialog {
  width: min(720px, calc(100vw - 32px));
  max-height: min(760px, calc(100dvh - 32px));
  padding: 0;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--surface-raised);
  color: var(--text-primary);
  box-shadow: var(--shadow-drawer);
}

.data-management-dialog::backdrop {
  background: var(--overlay-scrim);
}

.data-management-dialog__panel {
  display: grid;
  gap: var(--space-5);
  padding: var(--space-5);
  overflow: auto;
  max-height: inherit;
}

.data-management-dialog__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
}

.data-management-dialog__header h2 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-xl);
}

.data-management-dialog__close {
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  padding: 0;
  font-size: var(--text-xl);
  line-height: 1;
}

.data-management-dialog__intro,
.data-management-card p,
.data-management-status {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.5;
}

.data-management-summary {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-2);
}

.data-management-summary > div {
  display: grid;
  gap: var(--space-1);
  min-width: 0;
  padding: var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-subtle);
}

.data-management-summary__label {
  color: var(--text-muted);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.data-management-summary strong {
  font-size: var(--text-sm);
  overflow-wrap: anywhere;
}

.data-management-actions {
  display: grid;
  gap: var(--space-3);
}

.data-management-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: var(--space-4);
  align-items: center;
  padding: var(--space-4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
}

.data-management-card h3 {
  margin: 0 0 var(--space-1);
  font-size: var(--text-base);
}

.data-management-card--danger {
  border-color: var(--feedback-incorrect-soft);
}

.data-management-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 var(--space-4);
  white-space: nowrap;
}

.data-management-button:not(.data-management-button--secondary):not(.data-management-button--danger) {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-accent);
  color: var(--surface-base);
}

.data-management-button--danger {
  border-color: var(--feedback-incorrect-accent);
  background: var(--feedback-incorrect-soft);
  color: var(--feedback-incorrect-ink);
}

.data-import-controls {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.data-import-filename {
  max-width: 210px;
  color: var(--text-muted);
  font-size: var(--text-xs);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.data-import-preview,
.data-reset-confirmation {
  grid-column: 1 / -1;
  display: grid;
  gap: var(--space-2);
  padding: var(--space-3);
  border-radius: var(--radius-md);
  background: var(--feedback-info-soft);
}

.data-reset-confirmation {
  background: var(--feedback-incorrect-soft);
  color: var(--feedback-incorrect-ink);
}

.data-reset-confirmation > div {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.data-management-status {
  min-height: 1.5em;
  font-size: var(--text-sm);
}

@media (max-width: 680px) {
  .data-management-dialog {
    width: calc(100vw - 16px);
    max-height: calc(100dvh - 16px);
    border-radius: var(--radius-md);
  }

  .data-management-dialog__panel {
    gap: var(--space-4);
    padding: var(--space-4);
  }

  .data-management-summary {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .data-management-card {
    grid-template-columns: minmax(0, 1fr);
  }

  .data-management-card > .data-management-button,
  .data-import-controls {
    justify-self: stretch;
  }

  .data-import-controls {
    justify-content: flex-start;
  }
}

/* Step 22: reusable ClassWiz calculator support */
.classwiz-support-button {
  min-height: var(--touch-target-min);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-pill);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.classwiz-support-button:hover {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
}

.classwiz-support-button__icon {
  min-width: 24px;
  height: 22px;
  display: inline-grid;
  place-items: center;
  padding: 0 5px;
  border-radius: var(--radius-sm);
  background: var(--surface-subtle);
  color: var(--text-primary);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  font-style: italic;
}

.classwiz-support-scrim {
  position: absolute;
  inset: 0;
  z-index: 40;
  width: 100%;
  height: 100%;
  border: 0;
  background: var(--overlay-scrim);
  opacity: 0.72;
  cursor: pointer;
}

.classwiz-support-scrim:not([hidden]) { display: block; }

.classwiz-support-panel {
  position: absolute;
  inset: 0 0 0 auto;
  z-index: 50;
  width: min(500px, calc(100% - 56px));
  min-width: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  border-left: 1px solid var(--border-default);
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  background: var(--surface-base);
  box-shadow: var(--shadow-drawer);
  transform: translateX(calc(100% + var(--space-4)));
  visibility: hidden;
  transition: transform var(--motion-normal) var(--motion-easing), visibility 0s linear var(--motion-normal);
}

.app-shell[data-classwiz-open="true"] .classwiz-support-panel {
  transform: translateX(0);
  visibility: visible;
  transition-delay: 0s;
}

.classwiz-support-panel__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--divider-default);
}

.classwiz-support-panel__header .eyebrow { margin: 0; }
.classwiz-support-panel__header h2 {
  margin: var(--space-1) 0 0;
  font-size: var(--text-xl);
  letter-spacing: -0.025em;
}

.classwiz-support-panel__close {
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--surface-subtle);
  color: var(--text-secondary);
  font-size: var(--text-xl);
  line-height: 1;
  cursor: pointer;
}

.classwiz-support-panel__close:hover {
  border-color: var(--border-default);
  background: var(--surface-base);
  color: var(--text-primary);
}

.classwiz-support-panel__body {
  min-height: 0;
  overflow: auto;
  padding: var(--space-5);
  overscroll-behavior: contain;
}

.classwiz-support-panel__intro,
.classwiz-support-panel__return-note,
.classwiz-support-section p {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}

.classwiz-support-panel__intro { margin: 0 0 var(--space-4); }

.classwiz-use-case-tabs,
.classwiz-model-tabs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.classwiz-use-case-tabs button,
.classwiz-model-tabs button {
  min-height: var(--touch-target-min);
  padding: 0 var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-base);
  color: var(--text-secondary);
  font-weight: var(--weight-semibold);
  cursor: pointer;
}

.classwiz-use-case-tabs button[aria-selected="true"],
.classwiz-model-tabs button[aria-selected="true"] {
  border-color: var(--feedback-info-accent);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
}

.classwiz-support-section {
  margin-top: var(--space-4);
  padding: var(--space-4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-subtle);
}

.classwiz-support-section__heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-3);
}

.classwiz-support-section__heading > strong { font-size: var(--text-sm); }
.classwiz-support-section__eyebrow {
  margin: 0 0 var(--space-2) !important;
  color: var(--text-primary) !important;
  font-size: var(--text-xs) !important;
  font-weight: var(--weight-bold);
  letter-spacing: 0.045em;
  text-transform: uppercase;
}
.classwiz-support-section > p:last-child { margin-bottom: 0; }

.classwiz-example {
  margin-top: var(--space-3);
  padding: var(--space-3);
  border-left: 3px solid var(--feedback-info-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--surface-base);
}
.classwiz-example strong { font-size: var(--text-xs); }
.classwiz-example p { margin: var(--space-1) 0 0; }

.classwiz-radians-reminder {
  margin: var(--space-3) 0 0 !important;
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--feedback-warning-accent);
  border-radius: var(--radius-md);
  background: var(--feedback-warning-soft);
  color: var(--feedback-warning-ink) !important;
  font-weight: var(--weight-semibold);
}

.classwiz-steps {
  display: grid;
  gap: var(--space-2);
  margin: var(--space-3) 0 0;
  padding: 0;
  list-style: none;
}
.classwiz-step {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: var(--space-3);
  align-items: start;
  padding: var(--space-2) 0;
}
.classwiz-step + .classwiz-step { border-top: 1px solid var(--divider-default); }
.classwiz-step__number {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-pill);
  background: var(--feedback-info-soft);
  color: var(--feedback-info-ink);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
}
.classwiz-step__copy { display: grid; gap: 2px; }
.classwiz-step__copy strong { font-size: var(--text-sm); }
.classwiz-step__copy span {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}

.classwiz-support-section--warning { background: var(--surface-base); }
.classwiz-support-panel__return-note {
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: 1px solid var(--divider-default);
  color: var(--text-muted);
  font-size: var(--text-xs);
}

.app-shell[data-classwiz-open="true"] .vocabulary-popover {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

@media (max-width: 680px) {
  .classwiz-support-button {
    min-height: var(--touch-target-min);
    padding: 0 var(--space-2);
  }
  .classwiz-support-button__label { display: none; }
  .classwiz-support-panel {
    width: min(100%, 480px);
    border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  }
  .classwiz-support-panel__header,
  .classwiz-support-panel__body { padding: var(--space-4); }
}

@media (prefers-reduced-motion: reduce) {
  .classwiz-support-panel { transition: none; }
}

/* Step 37: topics may intentionally implement only a subset of the frozen five modes. */
.mode-tab:disabled,
.mode-tab[aria-disabled="true"] {
  cursor: not-allowed;
  opacity: 0.42;
}