/* Pygments syntax highlighting */
.highlight {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  overflow-x: auto;
  margin: var(--space-4) 0;
}

.highlight pre {
  margin: 0;
  padding: 0;
  border: none;
  background: transparent;
  font-family: var(--font-mono);
  font-variant-ligatures: none;
  font-feature-settings: "liga" 0, "calt" 0;
  font-size: var(--font-size-sm);
  line-height: 1.6;
}

.lesson-body code {
  font-variant-ligatures: none;
  font-feature-settings: "liga" 0, "calt" 0;
}

/* Lesson body typography */
.lesson-body h2 {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.lesson-body h3 {
  margin-top: 2rem;
  color: var(--color-primary);
}

.lesson-body p {
  color: var(--color-text-muted);
  line-height: 1.8;
}

.lesson-body ul, .lesson-body ol {
  color: var(--color-text-muted);
  padding-left: 1.5rem;
  line-height: 1.8;
}

.lesson-body table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-4) 0;
  font-size: var(--font-size-sm);
}

.lesson-body th, .lesson-body td {
  border: 1px solid var(--color-border);
  padding: var(--space-2) var(--space-3);
  text-align: left;
}

.lesson-body th {
  background: var(--color-bg-subtle);
  font-weight: 600;
}

.lesson-body blockquote {
  border-left: 4px solid var(--color-primary);
  margin: var(--space-4) 0;
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-subtle);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--color-text-muted);
}

/* Lesson sidebar */
.lesson-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: var(--space-8);
  align-items: start;
}

.lesson-sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 1rem);
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  max-height: calc(100vh - var(--nav-height) - 2rem);
  overflow-y: auto;
}

.lesson-sidebar h4 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  margin: 0 0 var(--space-3);
}

.lesson-sidebar ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.lesson-sidebar ul li {
  margin-bottom: var(--space-1);
}

.lesson-sidebar ul li a {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  display: block;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
}

.lesson-sidebar ul li a:hover,
.lesson-sidebar ul li a.active {
  background: var(--color-bg-muted);
  color: var(--color-primary);
  text-decoration: none;
}

.lesson-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
  gap: var(--space-4);
}

/* Course and module navigation */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

.eyebrow {
  margin: 0 0 var(--space-2);
  color: var(--color-primary);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.course-hero {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--space-6);
  margin-bottom: var(--space-6);
}

.course-hero h1, .module-hero h1, .course-page h1 { margin: 0; }
.course-lead { max-width: 760px; font-size: var(--font-size-lg); color: var(--color-text-muted); }
.course-audience { margin-bottom: 0; color: var(--color-text-muted); }
.course-actions { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-bottom: var(--space-8); }
.progress-card { margin-bottom: var(--space-6); }
.progress-card h2 { margin-top: 0; }

.course-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-8);
  overflow: hidden;
}

.course-stats div { padding: var(--space-4); text-align: center; border-right: 1px solid var(--color-border); }
.course-stats div:last-child { border-right: 0; }
.course-stats strong, .course-stats span { display: block; }
.course-stats strong { color: var(--color-primary); font-size: 1.35rem; }
.course-stats span { color: var(--color-text-muted); font-size: 0.8rem; }

.course-information { display: grid; grid-template-columns: 2fr 1fr; gap: var(--space-4); margin-bottom: var(--space-8); }
.course-information h2 { margin-top: 0; font-size: 1.1rem; }
.course-information p { margin-bottom: 0; color: var(--color-text-muted); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: var(--space-4); }
.section-heading h2 { margin: 0; }
.section-heading > p { color: var(--color-text-muted); }

.module-grid { display: grid; gap: var(--space-4); margin-top: var(--space-4); }
.module-card { border: 1px solid var(--color-border); border-radius: var(--radius-md); overflow: hidden; }
.module-card-header { display: flex; gap: var(--space-4); padding: var(--space-4) var(--space-6); background: var(--color-bg-subtle); }
.module-card-header h3 { margin: 0; }
.module-card-header p { margin: var(--space-1) 0 0; color: var(--color-text-muted); font-size: var(--font-size-sm); }
.module-number { color: var(--color-primary); font-family: var(--font-mono); font-weight: 700; }
.lesson-list { list-style: none; margin: 0; padding: 0; }
.lesson-list li { border-top: 1px solid var(--color-border); }
.lesson-list a { display: flex; justify-content: space-between; gap: var(--space-4); padding: var(--space-3) var(--space-6); color: var(--color-text); text-decoration: none; }
.lesson-list a:hover { background: var(--color-bg-subtle); }
.lesson-list small { color: var(--color-text-muted); white-space: nowrap; }
.empty-state { padding: var(--space-3) var(--space-6); color: var(--color-text-muted); }
.module-link { display: block; padding: var(--space-3) var(--space-6); border-top: 1px solid var(--color-border); font-size: var(--font-size-sm); font-weight: 600; }

.course-resources, .certification-action { margin-top: var(--space-8); }
.course-resources li { margin-bottom: var(--space-2); }
.course-resources li span { display: block; color: var(--color-text-muted); font-size: var(--font-size-sm); }
.module-hero { max-width: 760px; margin-bottom: var(--space-8); }
.module-hero > p:last-child { color: var(--color-text-muted); font-size: var(--font-size-lg); }
.module-lesson-cards { list-style: none; padding: 0; display: grid; gap: var(--space-3); }
.module-lesson-cards a { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: var(--space-4); padding: var(--space-4); border: 1px solid var(--color-border); border-radius: var(--radius-md); color: var(--color-text); text-decoration: none; }
.module-lesson-cards a:hover { border-color: var(--color-primary); background: var(--color-bg-subtle); }
.module-lesson-cards small { display: block; color: var(--color-text-muted); }
.lesson-sequence { color: var(--color-primary); font-family: var(--font-mono); font-weight: 700; }
.module-check { margin-top: var(--space-8); }
.module-check h2 { margin-top: 0; }
.course-page { max-width: 880px; margin: 0 auto; }
.course-page > header { margin-bottom: var(--space-8); }

@media (max-width: 768px) {
  .course-hero, .section-heading { align-items: flex-start; flex-direction: column; }
  .course-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course-stats div:nth-child(2) { border-right: 0; }
  .course-stats div:nth-child(-n+2) { border-bottom: 1px solid var(--color-border); }
  .course-information { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .lesson-layout {
    grid-template-columns: 1fr;
  }

  .lesson-sidebar {
    position: static;
    max-height: none;
  }
}
.concept-diagram {
  margin: 0 0 2rem;
  padding: 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  background: var(--color-bg-subtle);
  overflow-x: auto;
}

.concept-diagram__canvas {
  min-width: 520px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.7rem;
  min-height: 110px;
}

.concept-diagram figcaption {
  margin-top: 0.75rem;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  text-align: center;
}

.diagram-node, .diagram-output, .diagram-domain, .diagram-register,
.diagram-gate, .diagram-state, .diagram-module, .diagram-memory,
.diagram-stack span, .diagram-fifo span {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 0.65rem 0.8rem;
  background: var(--color-bg);
  text-align: center;
  white-space: nowrap;
}

.diagram-gate, .diagram-state, .diagram-register {
  border-color: var(--color-primary);
}

.diagram-output {
  background: color-mix(in srgb, var(--color-primary) 12%, var(--color-bg));
}

.diagram-arrow, .diagram-lines, .diagram-return, .diagram-branch {
  color: var(--color-primary);
  font-weight: 700;
  white-space: nowrap;
}

.diagram-stack, .diagram-fifo, .diagram-memory, .diagram-inputs {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.diagram-fifo, .diagram-memory {
  flex-direction: row;
}

.diagram-module {
  min-width: 230px;
}

.diagram-module > div {
  display: flex;
  gap: 0.4rem;
  margin-top: 0.6rem;
}

.diagram-module span {
  flex: 1;
  padding: 0.4rem;
  border: 1px dashed var(--color-border);
  border-radius: 5px;
}

.diagram-word, .diagram-timeline {
  display: flex;
  align-items: stretch;
}

.diagram-word span, .diagram-timeline span {
  padding: 0.65rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
}

.diagram-word i, .diagram-timeline i {
  width: 2px;
  background: var(--color-primary);
}

.diagram-sign {
  background: color-mix(in srgb, var(--color-primary) 16%, var(--color-bg)) !important;
}

.diagram-note {
  max-width: 250px;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

@media (max-width: 700px) {
  .concept-diagram__canvas { justify-content: flex-start; }
}