:root {
  --bg: #07111f;
  --panel: #101a2e;
  --panel-2: #14223c;
  --panel-3: #0d1729;
  --line: #2b3f66;
  --text: #e7eefc;
  --muted: #a9bddf;
  --accent: #3ecf9d;
  --accent-2: #2f7de1;
  --warn: #ffd166;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
}

.wrap {
  max-width: none;
  margin: 0 auto;
  padding: 20px;
}

.main-content.course-layout {
  width: 100%;
  max-width: none;
  margin: 0;
  padding: 20px;
  display: grid;
  grid-template-columns: minmax(230px, 280px) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}

.main-content.course-layout .wrap {
  max-width: none;
  margin: 0;
  padding: 0;
}

.course-nav-pane {
  position: sticky;
  top: 14px;
  align-self: start;
}

.course-nav-title {
  margin: 0 0 10px;
  font-size: 1rem;
}

.course-nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 5px;
}

.course-nav-link {
  display: block;
  border-radius: 8px;
  border: 1px solid transparent;
  padding: 8px 10px;
  color: var(--text);
  text-decoration: none;
  line-height: 1.35;
  font-size: 14px;
}

.course-nav-link:hover {
  background: #172442;
  border-color: #3a4a72;
}

.course-nav-link.current {
  background: #22345e;
  border-color: #4a67a1;
  font-weight: 700;
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 14px;
}

.title-card {
  text-align: center;
  background: var(--panel-2);
}

.course-title {
  margin: 0 0 6px;
  color: var(--accent);
  font-size: 0.95rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

h1, h2, h3 {
  margin: 0 0 8px;
  line-height: 1.2;
}

h1 {
  font-size: clamp(1.8rem, 2.4vw, 3rem);
}

h2 {
  font-size: 1.15rem;
}

.meta, .status {
  color: var(--muted);
  margin: 0;
}

.status span + span::before {
  content: " ";
}

.graphic-card {
  padding: 12px;
  transition: margin 160ms ease, padding 160ms ease, border-radius 160ms ease;
}

.module-graphic {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 6px;
  cursor: zoom-in;
}

.module-graphic:focus-visible {
  outline: 3px solid var(--warn);
  outline-offset: 3px;
}

.graphic-card.is-expanded {
  width: 100vw;
  max-width: 100vw;
  margin-left: calc(50% - 50vw);
  margin-right: calc(50% - 50vw);
  padding: 12px 20px;
  border-left: 0;
  border-right: 0;
  border-radius: 0;
  position: relative;
  z-index: 10;
}

.graphic-card.is-expanded .module-graphic {
  border-radius: 0;
  cursor: zoom-out;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
  margin-top: 12px;
}

button, .btn {
  border: 0;
  border-radius: 8px;
  padding: 9px 12px;
  cursor: pointer;
  font-weight: 700;
  color: #fff;
  background: var(--accent-2);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  line-height: 1.2;
  min-height: 38px;
}

.btn.secondary {
  background: #4a5d8d;
}

a {
  color: #9bc1ff;
}

a:not(.btn) {
  text-decoration: underline;
  text-underline-offset: 2px;
}

a.course-nav-link {
  text-decoration: none;
}

button:focus-visible,
.btn:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
audio:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--warn);
  outline-offset: 2px;
}

button:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.65;
  cursor: not-allowed;
}

.narration-player-card {
  border-color: #3f537f;
}

.narration-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-start;
  gap: 8px;
  margin: 0 0 10px;
}

.narration-controls .narration-nav {
  margin-top: 0;
  justify-content: flex-start;
}

.narration-controls .btn,
.narration-controls button {
  min-height: 38px;
  height: 38px;
}

.narration-speed-label {
  font-size: 12px;
  color: var(--muted);
  margin-left: 4px;
}

.narration-speed {
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #0f1933;
  color: var(--text);
  padding: 7px 9px;
  min-height: 38px;
}

.narration-audio {
  width: 100%;
  margin-top: 2px;
}

.narration-cc {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid #4a5a72;
  background: var(--panel-3);
  color: var(--text);
  line-height: 1.45;
}

.narration-cc.hidden {
  display: none;
}

.narration-card p,
.summary-card p {
  margin: 0 0 12px;
}

.narration-card p:last-child,
.summary-card p:last-child {
  margin-bottom: 0;
}

.knowledge-check-card,
.final-check-card,
.summary-card {
  background: var(--panel-2);
}

.knowledge-check-card ul,
.final-check-card ul {
  margin: 8px 0 0;
  padding-left: 1.25rem;
}

.knowledge-check-card li,
.final-check-card li {
  margin: 5px 0;
}

details.answer {
  margin-top: 10px;
  border-top: 1px solid var(--line);
  padding-top: 10px;
}

details.answer summary {
  cursor: pointer;
  font-weight: 800;
  color: var(--accent);
}

.quiz-form {
  display: grid;
  gap: 10px;
}

.quiz-question {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px;
  margin: 0;
}

.quiz-question legend {
  font-weight: 800;
  margin-bottom: 8px;
}

.quiz-question label {
  display: block;
  margin: 6px 0;
}

.quiz-result {
  margin: 0;
  color: var(--accent);
  font-weight: 800;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

@media (max-width: 980px) {
  .main-content.course-layout {
    display: block;
    padding: 16px;
  }

  .course-nav-pane {
    position: static;
    margin-bottom: 12px;
  }
}


.version-note {
  margin: 8px auto 0;
  max-width: 980px;
  color: var(--muted);
  font-size: 0.88rem;
}