:root {
  --bg: #0b1020;
  --panel: #121a30;
  --panel-2: #152141;
  --line: #2a3a60;
  --text: #e7eefc;
  --muted: #a9bddf;
  --accent: #3ecf9d;
  --accent-2: #2f7de1;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

.wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 20px;
}

.main-content.course-layout {
  max-width: 1320px;
  margin: 0 auto;
  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: 12px;
  padding: 16px;
  margin-bottom: 14px;
}

.title-card {
  text-align: center;
}

.hidden {
  display: none !important;
}

.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: 8px;
  cursor: zoom-in;
}

.module-graphic:focus-visible {
  outline: 3px solid #ffd166;
  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;
}

.badge {
  display: inline-block;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: var(--accent);
  color: #082116;
  padding: 4px 9px;
  border-radius: 999px;
  font-weight: 700;
  margin-bottom: 8px;
}

h1, h2 { margin: 0 0 8px; }

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

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

button, .btn {
  border: 0;
  border-radius: 9px;
  padding: 9px 12px;
  cursor: pointer;
  font-weight: 700;
  color: #fff;
  background: var(--accent-2);
  text-decoration: none;
  display: inline-block;
}

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

ul { margin: 8px 0; }
li { margin: 5px 0; }
.progress { font-size: 13px; color: var(--muted); margin-top: 8px; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 1000;
  background: #ffffff;
  color: #0a1020;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: 0 0 8px 8px;
  text-decoration: none;
}

.skip-link:focus,
.skip-link:focus-visible {
  left: 12px;
  top: 0;
}

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 {
  outline: 3px solid #ffd166;
  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: 10px 0;
}

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

.narration-controls .btn,
.narration-controls button {
  min-height: 38px;
  box-sizing: border-box;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  line-height: 1.2;
}

.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;
}

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

.narration-cc {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid #4a5a72;
  background: #0f1933;
  color: #e7eefc;
  line-height: 1.45;
}

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

#quiz-result:focus {
  outline: none;
}

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

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

.quiz-question legend {
  font-weight: 700;
  margin-bottom: 8px;
}

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

@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;
  }
}