:root {
  --econ-navy: #17324d;
  --econ-blue: #2b6f9f;
  --econ-blue-soft: #edf6fc;
  --econ-green: #24745a;
  --econ-green-soft: #edf8f2;
  --econ-yellow: #a26c08;
  --econ-yellow-soft: #fff8df;
  --econ-red: #a33f3f;
  --econ-red-soft: #fff1ef;
  --econ-purple: #6d54a3;
  --econ-purple-soft: #f4f0fb;
  --econ-gray: #566270;
  --econ-gray-soft: #f3f5f7;
  --econ-line: #d9e0e7;
}

main.content {
  max-width: 820px;
}

main.content p,
main.content li {
  line-height: 1.75;
  text-wrap: pretty;
}

main.content,
main.content section,
.callout,
.callout-body-container,
.theorem-box,
.intuition-box {
  min-width: 0;
  max-width: 100%;
}

main.content p { margin-bottom: 1rem; }
main.content li + li { margin-top: 0.45rem; }
main.content mjx-container[display="true"] {
  display: block;
  max-width: 100%;
  margin-block: 1.15rem !important;
  overflow-x: auto;
  overflow-y: hidden;
}

main.content h2 {
  margin-top: 2.8rem;
  padding-bottom: 0.35rem;
  border-bottom: 2px solid #dbe7ef;
  color: var(--econ-navy);
}

main.content h3 {
  margin-top: 2rem;
  color: #24445f;
}

.course-kicker {
  margin: -0.5rem 0 1.6rem;
  color: #607083;
  font-size: 0.92rem;
  font-weight: 650;
  letter-spacing: 0.01em;
}

.course-hero {
  margin: 1rem 0 1.6rem;
  padding: 1.35rem 1.5rem;
  border: 1px solid #cddde8;
  border-left: 6px solid var(--econ-blue);
  border-radius: 0.6rem;
  background: linear-gradient(135deg, #f8fbfd, #edf6fc);
  color: var(--econ-navy);
  font-size: 1.08rem;
}

.callout {
  margin: 1.35rem 0;
  border-radius: 0.55rem;
  box-shadow: 0 3px 12px rgba(23, 50, 77, 0.05);
}

.callout-note {
  --callout-color: var(--econ-blue);
  --callout-bg: var(--econ-blue-soft);
}

.callout-note.callout {
  border-left-color: var(--econ-blue);
}

.callout-note .callout-header {
  background-color: var(--econ-blue-soft);
  color: var(--econ-navy);
}

.callout-tip {
  --callout-color: var(--econ-green);
  --callout-bg: var(--econ-green-soft);
}

.callout-tip.callout {
  border-left-color: var(--econ-green);
}

.callout-tip .callout-header {
  background-color: var(--econ-green-soft);
  color: #185642;
}

.callout-warning {
  --callout-color: var(--econ-yellow);
  --callout-bg: var(--econ-yellow-soft);
}

.callout-warning.callout {
  border-left-color: var(--econ-yellow);
}

.callout-warning .callout-header {
  background-color: var(--econ-yellow-soft);
  color: #704a05;
}

.callout-important {
  --callout-color: var(--econ-red);
  --callout-bg: var(--econ-red-soft);
}

.callout-important.callout {
  border-left-color: var(--econ-red);
}

.callout-important .callout-header {
  background-color: var(--econ-red-soft);
  color: #762d2d;
}

.callout.answer {
  --callout-color: #637083;
  --callout-bg: #f7f8fa;
  margin-top: 0.65rem;
  box-shadow: none;
}

.callout.answer.callout {
  border-left-color: #637083;
}

.callout.answer .callout-header {
  background-color: #f1f3f5;
  color: #3f4a57;
}

.callout.answer .callout-header {
  font-weight: 700;
}

.callout.proof-extra {
  --callout-color: var(--econ-purple);
  --callout-bg: #faf8fd;
  border-left-color: var(--econ-purple);
  box-shadow: none;
}

.callout.proof-extra .callout-header {
  background-color: var(--econ-purple-soft);
  color: #4f3a79;
}

.theorem-box,
.intuition-box {
  margin: 1.35rem 0;
  padding: 1rem 1.15rem;
  border-radius: 0.55rem;
}

.theorem-box {
  border: 1px solid #d9cfee;
  border-left: 6px solid var(--econ-purple);
  background: var(--econ-purple-soft);
}

.intuition-box {
  border: 1px solid #d7dde2;
  border-left: 6px solid var(--econ-gray);
  background: var(--econ-gray-soft);
}

.source-note {
  color: #687789;
  font-size: 0.9rem;
}

.mindmap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.7rem;
  align-items: center;
  margin: 1.35rem 0;
}

.mind-col {
  display: grid;
  gap: 0.65rem;
}

.mind-leaf,
.mind-center {
  padding: 0.8rem;
  border: 1px solid var(--econ-line);
  border-radius: 0.55rem;
  background: #fff;
  text-align: center;
}

.mind-center {
  border: 3px solid var(--econ-blue);
  background: var(--econ-blue-soft);
  font-weight: 700;
}

.mind-arrow,
.dependency-arrow,
.arrow {
  color: var(--econ-blue);
  font-weight: 800;
  text-align: center;
}

.mind-arrow,
.dependency-arrow,
.flow .arrow { transform: rotate(90deg); }

.flow {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0.35rem;
  margin: 0.8rem 0;
}

.flow .node {
  display: flex;
  flex: 1 1 0;
  min-height: 4rem;
  align-items: center;
  justify-content: center;
  padding: 0.45rem;
  border: 1px solid var(--econ-line);
  border-radius: 0.5rem;
  background: #fff;
  text-align: center;
  font-size: 0.88rem;
  font-weight: 650;
}

.flow .node.current {
  border: 3px solid var(--econ-blue);
  background: var(--econ-blue-soft);
}

.course-sequence ol {
  display: grid;
  gap: 0.55rem;
  margin: 1rem 0;
  padding-left: 2.4rem;
}

.course-sequence li {
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--econ-line);
  border-left: 4px solid #aeb9c4;
  border-radius: 0.45rem;
  background: #fff;
}

.course-sequence.current-first li:first-child {
  border-left-color: var(--econ-blue);
  background: var(--econ-blue-soft);
}

.grid-2,
.grid-3,
.course-grid,
.study-routes {
  display: grid;
  gap: 1rem;
}

.grid-2 { grid-template-columns: 1fr; }

.grid-3,
.course-grid,
.study-routes {
  grid-template-columns: 1fr;
}

.course-card {
  padding: 1rem 1.05rem;
  border: 1px solid var(--econ-line);
  border-top: 5px solid var(--econ-blue);
  border-radius: 0.6rem;
  background: #fff;
  box-shadow: 0 5px 16px rgba(23, 50, 77, 0.06);
}

.course-card h3 {
  margin-top: 0;
  font-size: 1.05rem;
}

.course-card p {
  margin-bottom: 0;
  color: #526273;
  font-size: 0.94rem;
}

.dependency-map {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
  align-items: center;
}

.dependency-node {
  min-height: 8rem;
  padding: 1rem;
  border: 1px solid var(--econ-line);
  border-radius: 0.6rem;
  background: var(--econ-gray-soft);
  text-align: center;
}

.lecture-nav {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  align-items: center;
  margin-top: 3rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--econ-line);
}

.lecture-nav > :last-child {
  text-align: left;
}

.proof-map {
  padding: 1rem 1.15rem 1rem 2rem;
  border-left: 5px solid var(--econ-purple);
  background: var(--econ-purple-soft);
}

.math.display,
div.sourceCode {
  overflow-x: auto;
  overflow-y: hidden;
}

.math.inline {
  display: inline-block;
  max-width: 100%;
  overflow-x: auto;
  overflow-y: hidden;
  vertical-align: middle;
}

main.content table {
  display: block;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.columns {
  display: block !important;
}

.columns > .column {
  width: 100% !important;
  margin-bottom: 1rem;
}

@media (max-width: 900px) {
  .course-grid,
  .grid-3,
  .study-routes,
  .grid-2 {
    grid-template-columns: 1fr;
  }

  .mindmap,
  .dependency-map {
    grid-template-columns: 1fr;
  }

  .mind-arrow,
  .dependency-arrow {
    transform: rotate(90deg);
  }

  .flow {
    flex-direction: column;
  }

  .flow .arrow {
    transform: rotate(90deg);
  }
}

@media (max-width: 600px) {
  main.content {
    max-width: 100%;
  }

  .lecture-nav {
    grid-template-columns: 1fr;
  }

  .lecture-nav > :last-child {
    text-align: left;
  }
}