/* Course learning: a dense editorial workflow built on the shared RiseOJ
   tokens. Item type is encoded by geometry + label, never color alone. */

.lc-shell,
.lh-shell,
.lcb-shell {
  width: min(100% - 32px, 1380px);
  margin: 0 auto;
  padding: 30px 0 80px;
  color: var(--ink, var(--text));
}

.lc-breadcrumb {
  display: flex;
  gap: 8px;
  align-items: center;
  margin: 0 0 20px;
  color: var(--dim);
  font-size: 12px;
}
.lc-breadcrumb a { color: inherit; }
.lc-breadcrumb a:hover { color: var(--indigo); }

.lc-eyebrow,
.lc-panel-label {
  display: block;
  color: var(--dim);
  font: 600 10.5px/1.3 var(--font-mono-ds, var(--font-mono));
  letter-spacing: .11em;
  text-transform: uppercase;
}
.lc-eyebrow::before { content: "+"; margin-right: 7px; color: var(--indigo); }

.lc-course-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 56px;
  align-items: end;
  padding: 28px 0 32px;
  border-bottom: 1px solid var(--hair);
}
.lc-course-copy h1,
.lh-head h1,
.lcb-head h1 {
  margin: 8px 0 10px;
  color: var(--ink);
  font-family: var(--font-display);
  font-size: 38px;
  font-weight: 780;
  letter-spacing: -.03em;
  line-height: 1.08;
}
.lc-course-copy > p,
.lh-head > div:first-child > p {
  max-width: 72ch;
  margin: 0;
  color: var(--text-2);
  font-size: 14.5px;
  line-height: 1.7;
}
.lc-course-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin-top: 20px;
  color: var(--dim);
  font-size: 12px;
}
.lc-course-facts span + span { position: relative; }
.lc-course-facts span + span::before {
  content: "";
  position: absolute;
  top: 50%;
  left: -10px;
  width: 2px;
  height: 2px;
  border-radius: 50%;
  background: var(--dim);
}
.lc-course-facts b { color: var(--ink); font-weight: 600; }

.lc-course-progress {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 7px 14px;
  align-items: end;
}
.lc-course-progress > span {
  color: var(--dim);
  font-size: 11px;
  font-weight: 650;
  letter-spacing: .07em;
  text-transform: uppercase;
}
.lc-course-progress > strong { font-size: 24px; font-weight: 650; }
.lc-course-progress > small {
  grid-column: 1 / -1;
  color: var(--dim);
  font-size: 11px;
}
.lc-progress-track {
  grid-column: 1 / -1;
  height: 5px;
  overflow: hidden;
  border-radius: 99px;
  background: var(--hair);
}
.lc-progress-track i {
  display: block;
  width: 0;
  height: 100%;
  border-radius: inherit;
  background: var(--indigo);
  transition: width 180ms ease-out;
}

.lc-mode-tabs {
  display: flex;
  align-items: center;
  gap: 0;
  border-bottom: 1px solid var(--hair);
}
.lc-mode-tabs a {
  position: relative;
  padding: 14px 18px 12px;
  color: var(--dim);
  font-size: 12.5px;
  font-weight: 650;
  text-decoration: none;
}
.lc-mode-tabs a:hover { color: var(--ink); }
.lc-mode-tabs a.is-active { color: var(--ink); }
.lc-mode-tabs a.is-active::after {
  content: "";
  position: absolute;
  right: 18px;
  bottom: -1px;
  left: 18px;
  height: 2px;
  background: var(--indigo);
}
.lc-mode-tabs .lc-builder-link { margin-left: auto; color: var(--indigo); }
.lc-mock {
  margin: 16px 0 0;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
}
.lc-mock summary {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 11px 13px;
  color: var(--ink);
  font-size: 12px;
  font-weight: 650;
  cursor: pointer;
}
.lc-mock summary small { color: var(--dim); font-size: 10.5px; font-weight: 400; }
.lc-mock form {
  display: flex;
  gap: 10px;
  align-items: end;
  padding: 12px 13px;
  border-top: 1px solid var(--hair);
}
.lc-mock label { display: grid; gap: 5px; color: var(--dim); font-size: 10px; }

.lc-section-strip {
  display: flex;
  gap: 0;
  overflow-x: auto;
  margin: 22px 0 28px;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  scrollbar-width: thin;
}
.lc-section-strip a {
  display: grid;
  grid-template-columns: auto minmax(120px, 1fr) auto;
  gap: 8px;
  align-items: center;
  min-width: 205px;
  padding: 11px 13px;
  color: var(--dim);
  text-decoration: none;
  border-right: 1px solid var(--hair);
}
.lc-section-strip a:last-child { border-right: 0; }
.lc-section-strip a:hover,
.lc-section-strip a.is-current { background: var(--panel); color: var(--ink); }
.lc-section-strip a.is-current span { color: var(--indigo); }
.lc-section-strip strong {
  overflow: hidden;
  color: inherit;
  font-size: 12px;
  font-weight: 620;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.lc-section-strip span,
.lc-section-strip small { font-size: 10px; }

.lc-layout {
  display: grid;
  grid-template-columns: 190px minmax(0, 760px) minmax(180px, 230px);
  gap: 36px;
  align-items: start;
}
.lc-toc,
.lc-rail {
  position: sticky;
  top: 108px;
}
.lc-toc {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--hair);
}
.lc-toc > .lc-panel-label { padding: 13px 10px 9px; }
.lc-toc a {
  display: grid;
  grid-template-columns: 25px minmax(0, 1fr) auto;
  gap: 7px;
  padding: 9px 10px;
  border-top: 1px solid var(--hair);
  color: var(--dim);
  font-size: 11.5px;
  text-decoration: none;
}
.lc-toc a:hover { background: var(--panel); color: var(--ink); }
.lc-toc a span:nth-child(2) {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.lc-toc a small { font-size: 9px; }
.lc-toc .lc-legacy-link {
  display: block;
  margin-top: 16px;
  border-bottom: 1px solid var(--hair);
  color: var(--dim);
}

.lc-flow { min-width: 0; }
.lc-section {
  scroll-margin-top: 105px;
  padding: 0 0 64px;
}
.lc-section + .lc-section { padding-top: 10px; }
.lc-section-head {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr) auto;
  gap: 14px;
  align-items: end;
  margin-bottom: 24px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--hair);
}
.lc-section-no {
  color: var(--indigo);
  font-size: 13px;
  font-weight: 650;
}
.lc-level-label {
  display: block;
  margin-bottom: 4px;
  color: var(--dim);
  font: 600 10px/1.2 var(--font-mono-ds, var(--font-mono));
  letter-spacing: .07em;
  text-transform: uppercase;
}
.lc-section-head h2 {
  margin: 0;
  color: var(--ink);
  font-family: var(--font-display);
  font-size: 23px;
  font-weight: 760;
  letter-spacing: -.02em;
}
.lc-section-head p {
  max-width: 65ch;
  margin: 7px 0 0;
  color: var(--text-2);
  font-size: 13px;
  line-height: 1.55;
}
.lc-section-progress { text-align: right; }
.lc-section-progress strong { display: block; color: var(--ink); font-size: 14px; }
.lc-section-progress span { color: var(--dim); font-size: 9.5px; text-transform: uppercase; }

.lc-timeline {
  position: relative;
  padding-left: 42px;
}
.lc-timeline::before {
  content: "";
  position: absolute;
  top: 18px;
  bottom: 18px;
  left: 14px;
  width: 1px;
  background: var(--hair);
}
.lc-item {
  position: relative;
  margin-bottom: 12px;
  scroll-margin-top: 110px;
}
.lc-node-mark {
  position: absolute;
  top: 18px;
  left: -34px;
  z-index: 1;
  display: grid;
  width: 13px;
  height: 13px;
  place-items: center;
  border: 1px solid var(--border-strong);
  border-radius: 50%;
  background: var(--bg);
}
.lc-node-mark i { width: 4px; height: 4px; border-radius: 50%; background: var(--dim); }
.lc-item.is-complete .lc-node-mark { border-color: var(--ac); background: var(--ac); }
.lc-item.is-complete .lc-node-mark i {
  width: 5px;
  height: 3px;
  border: solid var(--bg);
  border-width: 0 0 1px 1px;
  border-radius: 0;
  background: transparent;
  transform: rotate(-45deg);
}
.lc-item.is-current .lc-node-mark {
  border-color: var(--indigo);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--indigo) 12%, transparent);
}

.lc-item-details {
  overflow: clip;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--panel) 34%, transparent);
}
.lc-item-details > summary {
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr) auto;
  gap: 11px;
  align-items: center;
  min-height: 62px;
  padding: 9px 13px;
  cursor: pointer;
  list-style: none;
}
.lc-item-details > summary::-webkit-details-marker { display: none; }
.lc-item-details > summary:hover { background: var(--panel); }
.lc-item-details > summary:focus-visible {
  outline: 2px solid var(--indigo);
  outline-offset: -2px;
}
.lc-item-details[open] > summary { border-bottom: 1px solid var(--hair); }
.lc-item.is-current .lc-item-details { border-color: color-mix(in srgb, var(--indigo) 55%, var(--hair)); }
.lc-item.is-locked { opacity: .58; }
.lc-item.is-locked summary { cursor: not-allowed; }
.lc-item.is-optional .lc-item-details { border-style: dashed; }

.lc-item-icon {
  position: relative;
  display: grid;
  width: 27px;
  height: 27px;
  place-items: center;
  color: var(--dim);
  border: 1px solid var(--border-strong);
  background: var(--bg);
}
.lc-item-icon::after {
  font: 700 10px/1 var(--font-mono-ds, var(--font-mono));
}
.lc-item-icon--lesson { border-radius: 3px; }
.lc-item-icon--lesson::after { content: "L"; }
.lc-item-icon--example { border-radius: 50%; }
.lc-item-icon--example::after { content: "▶"; font-size: 8px; }
.lc-item-icon--check_question { transform: rotate(45deg); border-radius: 2px; }
.lc-item-icon--check_question::after { content: "?"; transform: rotate(-45deg); }
.lc-item-icon--basic_problem { border-radius: 50%; }
.lc-item-icon--basic_problem::after { content: "B"; }
.lc-item-icon--practice_problem {
  clip-path: polygon(25% 7%,75% 7%,100% 50%,75% 93%,25% 93%,0 50%);
}
.lc-item-icon--practice_problem::after { content: "P"; }
.lc-item-icon--challenge_problem {
  clip-path: polygon(50% 0,93% 28%,80% 87%,20% 87%,7% 28%);
}
.lc-item-icon--challenge_problem::after { content: "C"; }
.lc-item-icon--checkpoint { border-radius: 2px; }
.lc-item-icon--checkpoint::after { content: "◇"; font-size: 15px; }
.lc-item-icon--review { border-radius: 50%; }
.lc-item-icon--review::after { content: "↻"; font-size: 14px; }
.lc-item-icon--project::after { content: "{}"; font-size: 8px; }
.lc-item-icon--promotion_test { border-radius: 50%; }
.lc-item-icon--promotion_test::after { content: "★"; }
.lc-item.is-current .lc-item-icon { color: var(--indigo); border-color: var(--indigo); }
.lc-item.is-complete .lc-item-icon { color: var(--ac); border-color: var(--ac); }

.lc-item-heading { min-width: 0; }
.lc-item-type {
  display: block;
  color: var(--dim);
  font: 600 9px/1.2 var(--font-mono-ds, var(--font-mono));
  letter-spacing: .08em;
  text-transform: uppercase;
}
.lc-item-heading strong {
  display: block;
  overflow: hidden;
  margin-top: 2px;
  color: var(--ink);
  font-size: 13.5px;
  font-weight: 650;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.lc-item-heading small {
  display: block;
  overflow: hidden;
  margin-top: 2px;
  color: var(--dim);
  font-size: 11px;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.lc-item-meta {
  display: flex;
  gap: 8px;
  align-items: center;
  color: var(--dim);
  font-size: 9.5px;
}
.lc-required {
  padding: 2px 5px;
  border: 1px solid var(--hair);
  border-radius: var(--r-xs);
  font-size: 8.5px;
  font-weight: 700;
  letter-spacing: .05em;
  text-transform: uppercase;
}
.lc-state { white-space: nowrap; }
.lc-state--done { color: var(--ac); }
.lc-state--current { color: var(--indigo); }

.lc-item-body { padding: 18px 20px 20px; }
.lc-prose {
  max-width: 72ch;
  color: var(--text-2);
  font-size: 14px;
  line-height: 1.72;
}
.lc-prose > :first-child { margin-top: 0; }
.lc-prose > :last-child { margin-bottom: 0; }
.lc-prose h2,
.lc-prose h3,
.lc-prose h4 { color: var(--ink); }
.lc-prose pre {
  overflow-x: auto;
  padding: 14px;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
  background: var(--panel);
}
.lc-prose blockquote {
  margin: 16px 0;
  padding: 11px 14px;
  border: 1px solid var(--hair);
  background: color-mix(in srgb, var(--indigo) 5%, transparent);
}
.lc-item-actions,
.lc-question-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-top: 18px;
}
.lc-mark-complete:disabled { color: var(--ac); }

.lc-question fieldset { min-width: 0; margin: 0; padding: 0; border: 0; }
.lc-question legend {
  width: 100%;
  margin-bottom: 15px;
  color: var(--ink);
  font-size: 15px;
  font-weight: 650;
  line-height: 1.55;
}
.lc-options { display: grid; gap: 7px; }
.lc-options label { cursor: pointer; }
.lc-options input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
}
.lc-options label > span {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 11px 12px;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
  color: var(--text-2);
  font-size: 13px;
  line-height: 1.45;
}
.lc-options label > span i {
  flex: 0 0 14px;
  width: 14px;
  height: 14px;
  margin-top: 2px;
  border: 1px solid var(--border-strong);
  border-radius: 50%;
}
.lc-options input:checked + span {
  border-color: var(--indigo);
  background: color-mix(in srgb, var(--indigo) 7%, transparent);
  color: var(--ink);
}
.lc-options input:checked + span i {
  border: 4px solid var(--indigo);
}
.lc-options input:focus-visible + span {
  outline: 2px solid var(--indigo);
  outline-offset: 2px;
}
.lc-short-answer .input { width: min(100%, 420px); }
.lc-feedback {
  display: none;
  margin-top: 14px;
  padding: 11px 13px;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
  font-size: 13px;
  line-height: 1.55;
}
.lc-feedback.is-visible { display: block; }
.lc-feedback.is-correct {
  border-color: color-mix(in srgb, var(--ac) 45%, var(--hair));
  background: color-mix(in srgb, var(--ac) 7%, transparent);
  color: var(--ac);
}
.lc-feedback.is-wrong {
  border-color: color-mix(in srgb, var(--wa) 45%, var(--hair));
  background: color-mix(in srgb, var(--wa) 7%, transparent);
  color: var(--wa);
}
.lc-back-link { color: var(--dim); font-size: 12px; }

.lc-example {
  margin: 16px 0;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
}
.lc-example-stage {
  min-height: 120px;
  padding: 18px;
  background: var(--panel);
}
.lc-example-stage ol { display: flex; flex-wrap: wrap; gap: 8px; margin: 0; padding: 0; list-style: none; }
.lc-example-stage li {
  min-width: 36px;
  padding: 8px;
  border: 1px solid var(--hair);
  border-radius: var(--r-xs);
  color: var(--ink);
  text-align: center;
}
.lc-example-stage li.is-active { border-color: var(--indigo); color: var(--indigo); }
.lc-example-stage p { margin: 12px 0 0; color: var(--text-2); font-size: 13px; }
.lc-diagram {
  display: grid;
  gap: 14px;
  margin: 0;
  min-width: 0;
}
.lc-diagram ol {
  justify-content: center;
  flex-wrap: nowrap;
  overflow-x: auto;
  padding: 4px 0 8px;
}
.lc-diagram--bits li {
  position: relative;
  min-width: 42px;
  font-family: var(--font-mono-ds, var(--font-mono));
}
.lc-diagram--bits li::after {
  content: attr(data-index);
  position: absolute;
  top: 100%;
  left: 50%;
  color: var(--dim);
  font-size: 9px;
  transform: translateX(-50%);
}
.lc-diagram li.is-done {
  border-color: color-mix(in srgb, var(--ac) 52%, var(--hair));
  background: color-mix(in srgb, var(--ac) 7%, transparent);
}
.lc-diagram li.is-muted { opacity: .45; }
.lc-diagram-flow {
  display: flex;
  gap: 9px;
  align-items: center;
  justify-content: center;
  overflow-x: auto;
  padding: 8px 0;
}
.lc-diagram-node {
  display: inline-grid;
  min-width: 64px;
  min-height: 38px;
  padding: 7px 11px;
  place-items: center;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
  background: var(--bg);
  color: var(--ink);
  font: 600 12px/1.35 var(--font-mono-ds, var(--font-mono));
  text-align: center;
}
.lc-diagram-node.is-active {
  border-color: var(--indigo);
  background: color-mix(in srgb, var(--indigo) 8%, var(--bg));
  color: var(--indigo);
}
.lc-diagram-arrow {
  flex: 0 0 auto;
  color: var(--dim);
  font: 500 16px/1 var(--font-mono-ds, var(--font-mono));
}
.lc-diagram-grid {
  width: auto;
  max-width: 100%;
  margin: 0 auto;
  border-collapse: separate;
  border-spacing: 4px;
  font: 500 11px/1.2 var(--font-mono-ds, var(--font-mono));
}
.lc-diagram-grid th,
.lc-diagram-grid td {
  min-width: 34px;
  height: 34px;
  padding: 5px;
  border: 1px solid var(--hair);
  border-radius: var(--r-xs);
  background: var(--bg);
  color: var(--text-2);
  text-align: center;
}
.lc-diagram-grid th { color: var(--dim); font-weight: 550; }
.lc-diagram-grid .is-active {
  border-color: var(--indigo);
  background: color-mix(in srgb, var(--indigo) 8%, var(--bg));
  color: var(--indigo);
  font-weight: 700;
}
.lc-diagram-tree { display: grid; gap: 18px; padding: 4px 0; }
.lc-diagram-tree-row {
  position: relative;
  display: flex;
  gap: 32px;
  justify-content: center;
}
.lc-diagram-tree-row + .lc-diagram-tree-row::before {
  content: "";
  position: absolute;
  top: -10px;
  left: 18%;
  right: 18%;
  height: 1px;
  background: var(--hair);
}
.lc-diagram figcaption {
  max-width: 62ch;
  margin: 0 auto;
  color: var(--dim);
  font-size: 11px;
  line-height: 1.5;
  text-align: center;
}
.lc-example-explanation {
  max-width: 65ch;
  margin: 14px auto 0 !important;
  text-align: center;
}
.lc-example-controls {
  display: flex;
  gap: 8px;
  align-items: center;
  padding: 9px;
  border-top: 1px solid var(--hair);
}
.lc-example-controls span { margin: 0 auto; color: var(--dim); font-size: 11px; }

.lc-problem-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 20px;
  align-items: center;
}
.lc-problem-id { color: var(--indigo); font-size: 11px; }
.lc-problem-row h4 { margin: 4px 0 6px; color: var(--ink); font-size: 16px; }
.lc-problem-row p { margin: 0; color: var(--dim); font-size: 12.5px; }
.lc-problem-actions { display: flex; gap: 10px; align-items: center; }
.lc-lock-copy strong { color: var(--ink); font-size: 13px; }
.lc-lock-copy ul { margin: 8px 0 0; color: var(--dim); font-size: 12px; }

.lc-rail { display: grid; gap: 18px; }
.lc-rail-panel {
  padding: 14px 0;
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}
.lc-rail-panel strong { display: block; margin-top: 10px; color: var(--ink); font-size: 13px; }
.lc-rail-panel small { display: block; margin-top: 4px; color: var(--dim); line-height: 1.45; }
.lc-rail-panel > a { display: inline-block; margin-top: 11px; color: var(--indigo); font-size: 12px; }
.lc-rail-panel dl { margin: 8px 0 0; }
.lc-rail-panel dl div {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  color: var(--dim);
  font-size: 11px;
}
.lc-rail-panel dt,
.lc-rail-panel dd { margin: 0; }

/* Problem-set mode */
.lc-problem-mode { max-width: 1040px; margin: 0 auto; }
.lc-problem-section { scroll-margin-top: 100px; padding: 0 0 46px; }
.lc-problem-section > header {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr) auto;
  gap: 14px;
  align-items: end;
  margin-bottom: 14px;
}
.lc-problem-section > header > span { color: var(--indigo); font-size: 12px; }
.lc-problem-section h2 { margin: 0; color: var(--ink); font-size: 20px; }
.lc-problem-section p { margin: 4px 0 0; color: var(--dim); font-size: 12px; }
.lc-problem-section header small { color: var(--dim); }
.lc-problem-table { overflow: hidden; border: 1px solid var(--hair); border-radius: var(--r-md); }
.lc-problem-head,
.lc-problem-table-row {
  display: grid;
  grid-template-columns: 22px 45px 100px minmax(200px, 1fr) 155px;
  gap: 10px;
  align-items: center;
}
.lc-problem-head {
  min-height: 34px;
  padding: 0 13px;
  border-bottom: 1px solid var(--hair);
  color: var(--dim);
  font: 600 9.5px/1 var(--font-mono-ds, var(--font-mono));
  letter-spacing: .09em;
  text-transform: uppercase;
}
.lc-problem-table-row {
  min-height: 49px;
  padding: 7px 13px;
  border-bottom: 1px solid var(--hair);
  color: var(--dim);
  font-size: 12px;
  text-decoration: none;
}
.lc-problem-table-row:last-child { border-bottom: 0; }
.lc-problem-table-row:hover { background: var(--panel); }
.lc-problem-table-row strong { color: var(--ink); font-size: 13.5px; font-weight: 620; }
.lc-problem-status {
  width: 8px;
  height: 8px;
  justify-self: center;
  border: 1px solid var(--border-strong);
  border-radius: 50%;
}
.lc-problem-table-row.is-solved {
  background: color-mix(in srgb, var(--ac) 6%, transparent);
}
.lc-problem-table-row.is-solved .lc-problem-status { border-color: var(--ac); background: var(--ac); }
.lc-problem-table-row.is-solved strong,
.lc-problem-table-row.is-solved > .mono:nth-child(3) { color: var(--ac); }

.lc-empty {
  padding: 24px;
  border: 1px dashed var(--hair);
  color: var(--dim);
  text-align: center;
}
.lc-mobile-progress { display: none; }

/* Learning home */
.lh-shell { max-width: 1240px; }
.lh-head {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(280px, .75fr);
  gap: 60px;
  align-items: end;
  padding: 34px 0 42px;
  border-bottom: 1px solid var(--hair);
}
.lh-head h1 { font-size: 42px; }
.lh-current-level {
  padding: 18px 0;
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}
.lh-current-level > span { color: var(--dim); font-size: 10px; text-transform: uppercase; }
.lh-current-level strong { display: block; margin-top: 7px; color: var(--ink); font-size: 19px; }
.lh-current-level p { margin: 6px 0 0; color: var(--dim); font-size: 12.5px; }
.lh-level-progress { margin: 14px 0 0; }
.lh-level-progress div {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 6px 0;
  border-top: 1px solid var(--hair);
  color: var(--dim);
  font-size: 10.5px;
}
.lh-level-progress dt,
.lh-level-progress dd { margin: 0; }
.lh-level-progress dd { color: var(--ink); }
.lh-continue,
.lh-legacy {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: center;
  padding: 24px 0;
  border-bottom: 1px solid var(--hair);
}
.lh-continue h2,
.lh-legacy h2 { margin: 5px 0 4px; color: var(--ink); font-size: 21px; }
.lh-continue p,
.lh-legacy p { margin: 0; color: var(--dim); font-size: 12.5px; }
.lh-levels,
.lh-required,
.lh-courses { padding: 54px 0; border-bottom: 1px solid var(--hair); }
.lh-section-head {
  display: flex;
  justify-content: space-between;
  gap: 36px;
  align-items: end;
  margin-bottom: 24px;
}
.lh-section-head h2 { margin: 5px 0 0; color: var(--ink); font-size: 25px; }
.lh-section-head > p { max-width: 60ch; margin: 0; color: var(--dim); font-size: 12.5px; }
.lh-section-head > a { color: var(--dim); font-size: 12px; }
.lh-level-track {
  display: grid;
  grid-template-columns: repeat(10, minmax(90px, 1fr));
  margin: 0;
  padding: 0;
  overflow-x: auto;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  list-style: none;
}
.lh-level {
  min-width: 100px;
  padding: 15px 12px;
  border-right: 1px solid var(--hair);
}
.lh-level:last-child { border-right: 0; }
.lh-level > span { display: block; color: var(--dim); font-size: 10px; }
.lh-level strong { display: block; margin-top: 14px; color: var(--ink); font-size: 12px; }
.lh-level small { display: block; margin-top: 3px; color: var(--dim); font-size: 9.5px; }
.lh-level.is-past { background: color-mix(in srgb, var(--ac) 5%, transparent); }
.lh-level.is-current {
  background: color-mix(in srgb, var(--indigo) 8%, transparent);
  box-shadow: inset 0 -2px 0 var(--indigo);
}
.lh-level.is-current > span,
.lh-level.is-current strong { color: var(--indigo); }
.lh-course-list { border-top: 1px solid var(--hair); }
.lh-course-row {
  display: grid;
  grid-template-columns: 42px minmax(250px, 1fr) 80px 210px 24px;
  gap: 16px;
  align-items: center;
  min-height: 78px;
  padding: 11px 12px;
  border-bottom: 1px solid var(--hair);
  color: var(--dim);
  text-decoration: none;
}
.lh-course-row:hover { background: var(--panel); }
.lh-course-index { color: var(--indigo); font-size: 11px; }
.lh-course-main { min-width: 0; }
.lh-course-main strong { display: block; color: var(--ink); font-size: 15px; }
.lh-course-main small {
  display: block;
  overflow: hidden;
  margin-top: 4px;
  color: var(--dim);
  font-size: 11.5px;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.lh-course-level { color: var(--ink); font-size: 12px; }
.lh-course-counts { display: flex; gap: 14px; font-size: 10.5px; }
.lh-course-counts b { color: var(--ink); }
.lh-course-next { font-size: 17px; transition: transform 160ms ease-out; }
.lh-course-row:hover .lh-course-next { transform: translateX(4px); color: var(--indigo); }
.lh-legacy > div:last-child { display: flex; gap: 8px; }

/* Course builder */
.lcb-shell { max-width: 1540px; }
.lcb-create { max-width: 760px; }
.lcb-create > .lcb-form { max-width: 620px; padding-top: 24px; }
.lcb-head {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: end;
  padding: 22px 0;
  border-bottom: 1px solid var(--hair);
}
.lcb-head h1 { margin-bottom: 3px; font-size: 30px; }
.lcb-head p { margin: 0; color: var(--dim); }
.lcb-head > div:last-child { display: flex; gap: 10px; align-items: center; }
.lcb-save-state { color: var(--dim); font-size: 11px; }
.lcb-save-state.is-saving { color: var(--indigo); }
.lcb-save-state.is-error { color: var(--wa); }
.lcb-layout {
  display: grid;
  grid-template-columns: 270px minmax(460px, 1fr) 340px;
  gap: 22px;
  align-items: start;
  padding-top: 22px;
}
.lcb-settings,
.lcb-editor {
  position: sticky;
  top: 102px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
}
.lcb-settings details {
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}
.lcb-settings details + details { border-top: 0; }
.lcb-settings summary {
  padding: 12px 4px;
  color: var(--ink);
  font-size: 12px;
  font-weight: 650;
  cursor: pointer;
}
.lcb-form { padding: 4px 0 16px; }
.lcb-form p,
.lcb-form > label {
  display: grid;
  gap: 5px;
  margin: 0 0 11px;
  color: var(--dim);
  font-size: 11px;
}
.lcb-form .input,
.lcb-form input,
.lcb-form textarea,
.lcb-form select { width: 100%; }
.lcb-form textarea { min-height: 78px; }
.lcb-form .errorlist { margin: 4px 0; padding: 0; color: var(--wa); list-style: none; }
.lcb-form small { color: var(--dim); line-height: 1.4; }
.lcb-level-form > div {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px;
  padding: 6px 0;
  border-top: 1px solid var(--hair);
}
.lcb-level-form label { color: var(--dim); font-size: 10.5px; }
.lcb-dependencies {
  margin-top: 16px;
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}
.lcb-dependencies summary { padding: 11px 0; color: var(--ink); font-size: 11px; cursor: pointer; }
.lcb-dependency-list {
  max-height: 230px;
  overflow-y: auto;
  margin-bottom: 10px;
  border: 1px solid var(--hair);
}
.lcb-dependency-list label {
  display: grid;
  grid-template-columns: 18px minmax(0, 1fr);
  gap: 6px;
  padding: 7px;
  border-bottom: 1px solid var(--hair);
  color: var(--dim);
  font-size: 10px;
}
.lcb-dependency-list label:last-child { border-bottom: 0; }
.lcb-dependency-list small { margin-right: 7px; color: var(--indigo); }
.lcb-section {
  margin-bottom: 16px;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--panel) 30%, transparent);
}
.lcb-section.is-dragging,
.lcb-item.is-dragging { opacity: .45; }
.lcb-section > header {
  display: grid;
  grid-template-columns: 24px 28px minmax(0, 1fr) auto;
  gap: 8px;
  align-items: center;
  min-height: 52px;
  padding: 7px 10px;
  border-bottom: 1px solid var(--hair);
}
.lcb-section header strong,
.lcb-section header small { display: block; }
.lcb-section header strong { color: var(--ink); font-size: 13px; }
.lcb-section header small { margin-top: 2px; color: var(--dim); font-size: 9.5px; }
.lcb-section header a { color: var(--dim); font-size: 11px; }
.lcb-drag {
  padding: 3px;
  border: 0;
  background: transparent;
  color: var(--dim);
  cursor: grab;
}
.lcb-items { min-height: 48px; }
.lcb-item {
  display: grid;
  grid-template-columns: 24px 28px minmax(0, 1fr) 34px auto 25px 25px;
  gap: 8px;
  align-items: center;
  min-height: 49px;
  padding: 6px 10px;
  border-bottom: 1px solid var(--hair);
}
.lcb-item > span:nth-child(3) { min-width: 0; }
.lcb-item strong,
.lcb-item small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.lcb-item strong { color: var(--ink); font-size: 12px; }
.lcb-item small { color: var(--dim); font-size: 9.5px; }
.lcb-item a { color: var(--dim); font-size: 10px; }
.lcb-item form { margin: 0; }
.lcb-item form button {
  width: 24px;
  height: 24px;
  padding: 0;
  border: 1px solid var(--hair);
  border-radius: var(--r-xs);
  background: transparent;
  color: var(--dim);
}
.lcb-add-item {
  display: block;
  padding: 10px;
  color: var(--dim);
  font-size: 11px;
  text-align: center;
}
.lcb-add-item:hover { color: var(--indigo); background: var(--panel); }
.lcb-drop-empty { margin: 0; padding: 16px; color: var(--dim); font-size: 11px; text-align: center; }
.lcb-editor {
  padding: 15px;
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
}
.lcb-editor > .lc-panel-label { margin-bottom: 13px; }
.lcb-question-editor {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--hair);
}
.lcb-question-editor > .lc-panel-label { margin-bottom: 12px; }
.lcb-option-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 5px 8px;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--hair);
}
.lcb-option-row > input:last-child { grid-column: 1 / -1; }
.lcb-option-row label {
  display: flex;
  gap: 5px;
  align-items: center;
  color: var(--dim);
  font-size: 10px;
}
.lcb-problem-search { position: relative; margin-bottom: 11px; }
.lcb-problem-search label { display: block; margin-bottom: 5px; color: var(--dim); font-size: 11px; }
.lcb-search-results {
  position: absolute;
  z-index: 3;
  top: 100%;
  right: 0;
  left: 0;
  max-height: 220px;
  overflow-y: auto;
  border: 1px solid var(--hair);
  background: var(--panel);
}
.lcb-search-results:empty { display: none; }
.lcb-search-results button {
  display: block;
  width: 100%;
  padding: 8px 10px;
  border: 0;
  border-bottom: 1px solid var(--hair);
  background: transparent;
  color: var(--ink);
  font-size: 11px;
  text-align: left;
}
.lcb-search-results button:hover { background: var(--bg); }

@media (max-width: 1180px) {
  .lc-layout { grid-template-columns: minmax(0, 1fr) 210px; }
  .lc-toc { display: none; }
  .lcb-layout { grid-template-columns: 220px minmax(440px, 1fr); }
  .lcb-editor { position: relative; top: auto; grid-column: 1 / -1; max-height: none; }
}

@media (max-width: 820px) {
  .lc-shell,
  .lh-shell,
  .lcb-shell { width: min(100% - 24px, 100%); padding-top: 74px; }
  .lc-course-head,
  .lh-head { grid-template-columns: 1fr; gap: 24px; }
  .lc-course-progress { max-width: 360px; }
  .lc-layout { grid-template-columns: 1fr; }
  .lc-rail { display: none; }
  .lc-section-strip { margin-inline: -12px; border-radius: 0; }
  .lh-level-track { grid-template-columns: repeat(10, 112px); }
  .lh-course-row { grid-template-columns: 32px minmax(0, 1fr) 70px 20px; }
  .lh-course-counts { display: none; }
  .lcb-layout { grid-template-columns: 1fr; }
  .lcb-settings,
  .lcb-editor { position: static; max-height: none; }
  .lcb-canvas { grid-row: 1; }
}

@media (max-width: 600px) {
  .lc-shell,
  .lh-shell,
  .lcb-shell { width: calc(100% - 20px); padding-bottom: 68px; }
  .lc-course-copy h1,
  .lh-head h1 { font-size: 29px; }
  .lc-course-head { padding-top: 12px; }
  .lc-course-facts { gap: 7px 15px; }
  .lc-mode-tabs { overflow-x: auto; }
  .lc-mode-tabs a { flex: 0 0 auto; padding-inline: 12px; }
  .lc-mode-tabs .lc-builder-link { margin-left: 0; }
  .lc-mock summary small { display: none; }
  .lc-mock form { align-items: stretch; flex-direction: column; }
  .lc-section-strip a { min-width: 175px; }
  .lc-section-head { grid-template-columns: 30px minmax(0, 1fr); }
  .lc-section-progress { display: none; }
  .lc-timeline { padding-left: 29px; }
  .lc-timeline::before { left: 8px; }
  .lc-node-mark { left: -27px; }
  .lc-item-details > summary { grid-template-columns: 29px minmax(0, 1fr); padding: 9px 10px; }
  .lc-item-meta { grid-column: 2; justify-content: flex-start; flex-wrap: wrap; }
  .lc-item-body { padding: 15px 13px 17px; }
  .lc-problem-row { grid-template-columns: 1fr; }
  .lc-problem-actions { justify-content: space-between; flex-wrap: wrap; }
  .lc-question-actions .btn { min-height: 42px; }
  .lc-problem-head { display: none; }
  .lc-problem-table-row {
    grid-template-columns: 18px minmax(0, 1fr) auto;
    gap: 7px 9px;
    padding: 10px;
  }
  .lc-problem-table-row > span:nth-child(2) { display: none; }
  .lc-problem-table-row > span:nth-child(3) { grid-column: 2; grid-row: 2; }
  .lc-problem-table-row > strong { grid-column: 2; grid-row: 1; }
  .lc-problem-table-row > .dp { grid-column: 3; grid-row: 1 / 3; }
  .lc-mobile-progress {
    position: fixed;
    z-index: calc(var(--z-nav, 100) - 1);
    right: 0;
    bottom: 0;
    left: 0;
    display: flex;
    justify-content: space-between;
    padding: 9px 12px;
    border-top: 1px solid var(--hair);
    background: var(--panel);
    color: var(--dim);
    font-size: 11px;
  }
  .lc-mobile-progress strong { color: var(--indigo); }
  .lh-continue,
  .lh-legacy,
  .lh-section-head { align-items: flex-start; flex-direction: column; }
  .lh-continue .btn { width: 100%; }
  .lh-course-row { grid-template-columns: 27px minmax(0, 1fr) 18px; }
  .lh-course-level { display: none; }
  .lh-legacy > div:last-child { width: 100%; flex-direction: column; }
  .lcb-item { grid-template-columns: 20px 24px minmax(0, 1fr) auto 24px 24px; }
  .lcb-item > .mono,
  .lcb-item > a { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .lc-progress-track i,
  .lh-course-next { transition: none !important; }
}