/* ============================================
   Pedagogy for Winds and Brass — Shared Styles
   ============================================ */

/* --- Design Tokens --- */
:root {
  --color-bg: #faf9f7;
  --color-text: #2c2c2c;
  --color-heading: #1a1a2e;
  --color-accent: #4a5568;
  --color-accent-hover: #2d3748;
  --color-border: #e2e0dc;
  --color-card-bg: #ffffff;
  --color-hero-overlay: rgba(26, 26, 46, 0.65);
  --color-progress-fill: #4a5568;
  --color-progress-track: #e2e0dc;
  --color-complete: #48854a;
  --color-link: #2b6cb0;
  --color-link-hover: #1a4971;
  --color-footer-bg: #1a1a2e;
  --color-footer-text: #e2e0dc;

  --font-heading: Georgia, 'Times New Roman', serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;

  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 6rem;

  --max-width: 960px;
  --nav-height: 64px;
}

/* --- Reset & Base --- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}

a:hover {
  color: var(--color-accent-hover);
  text-decoration: underline;
}

/* --- Typography --- */
h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-heading);
  line-height: 1.3;
  margin-top: 0;
}

h1 { font-size: 2.25rem; margin-bottom: var(--space-sm); }
h2 { font-size: 1.75rem; margin-bottom: var(--space-sm); }
h3 { font-size: 1.25rem; margin-bottom: var(--space-xs); }

p {
  margin-top: 0;
  margin-bottom: var(--space-sm);
}

blockquote {
  margin: 0 0 var(--space-sm) 0;
  padding-left: var(--space-sm);
  border-left: 3px solid var(--color-border);
  font-style: italic;
  color: var(--color-accent);
}

/* --- Layout Utilities --- */
.container {
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-sm);
  padding-right: var(--space-sm);
}

.section {
  padding-top: var(--space-lg);
  padding-bottom: var(--space-lg);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* --- Skip Link --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-sm);
  background: var(--color-heading);
  color: #fff;
  padding: var(--space-xs) var(--space-sm);
  z-index: 1000;
  border-radius: 0 0 4px 4px;
}

.skip-link:focus {
  top: 0;
}

/* --- Navigation --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  height: var(--nav-height);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-sm);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  color: var(--color-heading);
  text-decoration: none;
  font-weight: bold;
}

.nav-logo:hover {
  text-decoration: none;
  color: var(--color-heading);
}

.nav-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: var(--space-md);
}

.nav-links a {
  color: var(--color-text);
  font-size: 0.95rem;
  text-decoration: none;
  padding: var(--space-xs) 0;
}

.nav-links a:hover {
  color: var(--color-accent-hover);
  text-decoration: none;
  border-bottom: 2px solid var(--color-accent-hover);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-xs);
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-heading);
  position: relative;
}

.nav-toggle span::before,
.nav-toggle span::after {
  content: '';
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-heading);
  position: absolute;
  left: 0;
}

.nav-toggle span::before { top: -7px; }
.nav-toggle span::after { top: 7px; }

/* --- Hero Section --- */
.hero {
  background: linear-gradient(var(--color-hero-overlay), var(--color-hero-overlay)),
              url('../images/hero-home.jpg') center/cover no-repeat;
  min-height: 60vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-xl) var(--space-sm);
}

.hero-course {
  background-image: linear-gradient(var(--color-hero-overlay), var(--color-hero-overlay)),
                    url('../images/hero-course.jpg');
  min-height: 35vh;
}

.hero-content {
  max-width: 700px;
}

.hero h1 {
  color: #ffffff;
  font-size: 2.5rem;
  margin-bottom: var(--space-md);
  line-height: 1.3;
}

.hero p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.15rem;
  margin-bottom: var(--space-md);
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  padding: 0.75rem 2rem;
  font-size: 1rem;
  font-family: var(--font-body);
  border: none;
  border-radius: 4px;
  cursor: pointer;
  text-decoration: none;
  text-align: center;
  transition: background-color 0.2s ease;
}

.btn-primary {
  background-color: #ffffff;
  color: var(--color-heading);
  font-weight: 600;
}

.btn-primary:hover {
  background-color: #f0efed;
  color: var(--color-heading);
  text-decoration: none;
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-accent);
  border: 2px solid var(--color-accent);
}

.btn-secondary:hover {
  background-color: var(--color-accent);
  color: #ffffff;
  text-decoration: none;
}

.btn-complete {
  background-color: var(--color-complete);
  color: #ffffff;
}

.btn-complete:hover {
  background-color: #3a6f3c;
  text-decoration: none;
}

.btn-completed {
  background-color: var(--color-border);
  color: var(--color-accent);
  cursor: default;
}

/* --- Feature Cards --- */
.features-section {
  background-color: var(--color-card-bg);
}

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.feature-card {
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  text-align: center;
}

.feature-img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-radius: 4px;
  margin-bottom: var(--space-sm);
}

.feature-card h3 {
  margin-bottom: var(--space-xs);
}

.feature-card p {
  color: var(--color-accent);
  font-size: 0.95rem;
}

/* --- Instructor Bio --- */
.instructor {
  background-color: var(--color-card-bg);
}

.instructor-grid {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-md);
  align-items: start;
}

.instructor-photo {
  width: 280px;
  height: auto;
  border-radius: 6px;
  object-fit: cover;
}

.instructor-text h2 {
  margin-bottom: var(--space-xs);
}

.instructor-text .bio-link {
  display: inline-block;
  margin-top: var(--space-xs);
}

/* --- Course Page Layout --- */
.course-layout {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: var(--space-md);
  align-items: start;
}

/* --- Course Sidebar --- */
.course-sidebar {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-sm);
  background-color: var(--color-card-bg);
}

.chapter {
  margin-bottom: var(--space-sm);
}

.chapter:last-child {
  margin-bottom: 0;
}

.chapter h3 {
  font-size: 1rem;
  padding-bottom: var(--space-xs);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-xs);
}

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

.chapter li {
  margin-bottom: 2px;
}

.chapter li a {
  display: block;
  padding: 0.35rem 0.5rem;
  border-radius: 4px;
  font-size: 0.9rem;
  color: var(--color-text);
}

.chapter li a:hover {
  background-color: var(--color-bg);
  text-decoration: none;
}

.chapter li.completed a::before {
  content: '\2713 ';
  color: var(--color-complete);
  font-weight: bold;
}

/* --- Course Main Content --- */
.course-main {
  min-width: 0;
}

.course-resources {
  margin-top: var(--space-md);
}

.course-resources ul {
  list-style: none;
  padding: 0;
}

.course-resources li {
  margin-bottom: var(--space-xs);
}

.course-resources li a {
  padding: var(--space-xs) var(--space-sm);
  display: inline-block;
  border: 1px solid var(--color-border);
  border-radius: 4px;
}

.course-resources li a:hover {
  background-color: var(--color-card-bg);
  text-decoration: none;
}

/* --- Progress Bar --- */
.progress-container {
  margin-bottom: var(--space-md);
}

.progress-text {
  font-size: 0.95rem;
  margin-bottom: var(--space-xs);
  color: var(--color-accent);
}

.progress-bar {
  width: 100%;
  height: 12px;
  background-color: var(--color-progress-track);
  border-radius: 6px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: var(--progress-pct, 0%);
  background-color: var(--color-progress-fill);
  border-radius: 6px;
  transition: width 0.3s ease;
}

/* --- Course Action Buttons --- */
.course-actions {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-md);
  flex-wrap: wrap;
}

/* --- Community Section --- */
.community {
  text-align: center;
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  margin-bottom: var(--space-md);
}

.community-img {
  max-width: 100%;
  border-radius: 4px;
  margin-bottom: var(--space-sm);
}

.course-instructor-photo {
  width: 200px;
  height: auto;
  border-radius: 6px;
  margin-bottom: var(--space-sm);
}

/* --- Contact Page --- */
.contact-content h1 {
  margin-bottom: var(--space-md);
}

.contact-info {
  font-size: 1.05rem;
  line-height: 2;
}

.contact-info a {
  font-weight: 600;
}

/* --- Footer --- */
.site-footer {
  background-color: var(--color-footer-bg);
  color: var(--color-footer-text);
  padding: var(--space-lg) var(--space-sm);
  text-align: center;
}

.site-footer h3 {
  color: var(--color-footer-text);
  font-size: 1.1rem;
  margin-bottom: var(--space-sm);
}

.site-footer p {
  margin-bottom: var(--space-xs);
  font-size: 0.9rem;
}

.site-footer a {
  color: var(--color-footer-text);
  text-decoration: underline;
}

.site-footer a:hover {
  color: #ffffff;
}

/* --- Chapter Overview Images --- */
.lesson-content--wide {
  max-width: var(--max-width);
}

.overview-hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  align-items: start;
  margin-bottom: var(--space-md);
}

.overview-hero-image {
  width: 100%;
  border-radius: 6px;
  object-fit: cover;
}

.overview-hero-image-centered {
  display: block;
  max-width: 100%;
  margin: 0 auto var(--space-md);
  border-radius: 6px;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  /* Nav */
  .nav-toggle {
    display: block;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: var(--space-sm);
    gap: 0;
  }

  .nav-links li {
    border-bottom: 1px solid var(--color-border);
  }

  .nav-links li:last-child {
    border-bottom: none;
  }

  .nav-links a {
    display: block;
    padding: var(--space-sm) 0;
  }

  .site-nav.nav-open .nav-links {
    display: flex;
  }

  /* Hero */
  .hero {
    min-height: 45vh;
    padding: var(--space-lg) var(--space-sm);
  }

  .hero h1 {
    font-size: 1.75rem;
  }

  /* Features */
  .features {
    grid-template-columns: 1fr;
  }

  /* Instructor */
  .instructor-grid {
    grid-template-columns: 1fr;
    justify-items: center;
  }

  .instructor-photo {
    width: 200px;
    height: auto;
  }

  /* Course layout */
  .course-layout {
    grid-template-columns: 1fr;
  }

  /* Chapter overview grid */
  .overview-hero-grid {
    grid-template-columns: 1fr;
  }

  /* Lesson two-column layout */
  .lesson-two-col {
    grid-template-columns: 1fr;
  }

  /* General */
  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.5rem; }

  /* Lesson page responsive */
  .lesson-nav {
    flex-direction: column;
  }

  .lesson-nav a {
    text-align: center;
  }

  .drag-and-drop-container .image-container {
    max-width: 100%;
  }

  .drag-drop-container {
    flex-direction: column;
    align-items: center;
  }

  .drop-body-outline {
    min-height: 300px;
  }
}

/* ============================================
   Lesson Page Styles
   ============================================ */

/* --- Breadcrumb --- */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
}

.breadcrumb a {
  color: var(--color-accent);
}

.breadcrumb a:hover {
  color: var(--color-accent-hover);
}

/* --- Lesson Content --- */
.lesson-content {
  max-width: var(--max-width);
}

/* --- Lesson Two-Column Layout --- */
.lesson-two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  align-items: start;
  margin-bottom: var(--space-md);
}

.lesson-two-col.align-center {
  align-items: center;
}

/* --- Purple highlight box (used on instrument mouthpiece sections) --- */
.highlight-box-purple {
  background-color: hsla(294, 83%, 38%, 0.3);
  padding: 6%;
}

/* --- Accent Banner (gold heading block) --- */
.accent-banner {
  background-color: #ffc700;
  padding: 6%;
  border-radius: 6px;
  margin-bottom: var(--space-sm);
}

.accent-banner h2 {
  color: #ffffff;
  font-weight: 700;
  margin: 0;
}

/* --- History Highlight Section (yellow background) --- */
.history-highlight {
  background-color: #ffc700;
  padding: 6%;
  border-radius: 6px;
  margin: var(--space-md) 0;
}

.history-highlight h2 {
  margin-top: 0;
}

.history-highlight .images-side-by-side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin: var(--space-md) 0;
}

.history-highlight .images-side-by-side img {
  height: 250px;
  object-fit: cover;
}

@media (max-width: 768px) {
  .history-highlight .images-side-by-side {
    grid-template-columns: 1fr;
  }
}

/* --- Ready-to-Begin Checklist (yellow background, decorative checkboxes) --- */
.ready-checklist {
  background-color: #ffc700;
  padding: 6%;
  border-radius: 6px;
  margin: var(--space-md) 0;
}

.ready-checklist h2 {
  margin-top: 0;
}

.ready-checklist label {
  display: block;
  margin-bottom: var(--space-sm);
  font-size: 1rem;
  cursor: pointer;
}

.ready-checklist input[type="checkbox"] {
  margin-right: 0.5em;
  accent-color: var(--color-dark);
  cursor: pointer;
}

/* --- Bordered Text Block (accent stroke) --- */
.accent-bordered {
  border: 2px solid #ffc700;
  border-radius: 6px;
  padding: var(--space-md);
}

/* --- Lesson Feature Image (right column) --- */
.lesson-feature-img {
  width: 100%;
  height: auto;
  object-fit: contain;
  border-radius: 6px;
}

/* --- Toolbox Assignment Box --- */
.toolbox-assignment {
  background-color: #fffbeb;
  border: 3px solid #e6860a;
  border-radius: 8px;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  box-shadow: 0 2px 8px rgba(230, 134, 10, 0.15);
}

.toolbox-assignment h4 {
  margin-top: 0;
  color: var(--color-heading);
}

.toolbox-assignment ol {
  margin-bottom: 0;
}

/* --- Assignment / Toolbox Buttons --- */
.assignment-actions {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  margin: var(--space-md) 0;
}

.btn-accent {
  background-color: #ffc700;
  color: var(--color-heading);
  font-weight: 600;
}

.btn-accent:hover {
  background-color: #e6b400;
  color: var(--color-heading);
  text-decoration: none;
}

.lesson-content h2 {
  margin-top: var(--space-md);
}

.lesson-content h3 {
  margin-top: var(--space-sm);
}

.lesson-content ul,
.lesson-content ol {
  margin-top: 0;
  margin-bottom: var(--space-sm);
  padding-left: var(--space-md);
}

.lesson-content li {
  margin-bottom: var(--space-xs);
}

.lesson-content a {
  color: var(--color-link);
  text-decoration: underline;
}

.lesson-content a:hover {
  color: var(--color-link-hover);
}

/* --- Essential Question --- */
.essential-question {
  background-color: var(--color-card-bg);
  border-left: 4px solid var(--color-accent);
  padding: var(--space-sm) var(--space-md);
  margin-bottom: var(--space-md);
  border-radius: 0 6px 6px 0;
  font-style: italic;
  font-size: 1.1rem;
  color: var(--color-heading);
}

/* --- Formula highlight box (yellow background, large centered text) --- */
.formula-box {
  background-color: #ffc700;
  padding: var(--space-md);
  border-radius: 6px;
  margin: var(--space-md) 0;
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-heading);
}

/* --- Lesson Navigation (Prev/Next) --- */
.lesson-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

.lesson-nav a {
  flex: 0 1 auto;
}

/* --- Mark Complete Area --- */
.lesson-complete {
  margin-top: var(--space-lg);
  text-align: center;
}

/* --- Video Embed --- */
.video-embed {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  margin: var(--space-md) 0;
  border-radius: 6px;
}

.video-embed iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* --- Lesson Images --- */
.lesson-image {
  display: block;
  max-width: 100%;
  height: auto;
  margin: var(--space-md) auto;
  border-radius: 6px;
}

/* --- Multiple-Choice Quiz --- */
.quiz {
  margin: var(--space-md) 0;
}

.quiz-question {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
  margin-bottom: var(--space-sm);
  background-color: var(--color-card-bg);
}

.quiz-question legend {
  font-weight: 600;
  font-family: var(--font-heading);
  color: var(--color-heading);
  font-size: 1.05rem;
  margin-bottom: var(--space-sm);
  padding: 0;
}

.quiz-option {
  display: block;
  padding: 0.5rem 0.75rem;
  margin-bottom: 4px;
  border-radius: 4px;
  cursor: pointer;
  transition: background-color 0.15s ease;
}

.quiz-option:hover {
  background-color: var(--color-bg);
}

.quiz-option input[type="radio"] {
  margin-right: 0.5rem;
}

.quiz-feedback {
  margin-top: var(--space-sm);
  padding: var(--space-xs) var(--space-sm);
  border-radius: 4px;
  font-size: 0.95rem;
  display: none;
}

.quiz-feedback.correct {
  display: block;
  background-color: #e8f5e9;
  color: #2e7d32;
}

.quiz-feedback.incorrect {
  display: block;
  background-color: #fce4ec;
  color: #c62828;
}

.quiz-option.quiz-correct {
  background-color: #e8f5e9;
  border-color: #2e7d32;
  color: #2e7d32;
}

.quiz-option.quiz-incorrect {
  background-color: #fce4ec;
  border-color: #c62828;
  color: #c62828;
}

/* --- Checkbox Quiz Options --- */
.quiz-checkbox {
  display: block;
  padding: 0.75rem 1rem;
  margin-bottom: 0.5rem;
  border: 2px solid var(--color-border);
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
  background-color: var(--color-card-bg);
}

.quiz-checkbox:hover {
  background-color: var(--color-bg);
}

.quiz-checkbox input[type="checkbox"] {
  margin-right: 0.5rem;
}

.quiz-option.quiz-selected {
  background-color: #e3f2fd;
  border-color: #1565c0;
  outline: 2px solid #1565c0;
}

.quiz-submit,
.quiz-submit-matching {
  margin-top: var(--space-sm);
}

/* --- Assessment Check All --- */
.assessment-check-all {
  text-align: center;
  margin: var(--space-lg) 0 var(--space-md);
}

.assessment-results {
  margin: var(--space-md) 0;
  padding: var(--space-md);
  border-radius: 6px;
  background-color: var(--color-card-bg);
  border: 1px solid var(--color-border);
}

.assessment-results .results-score {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.assessment-results .results-review {
  color: #c62828;
}

/* --- Matching Exercise --- */
.matching-exercise {
  margin: var(--space-sm) 0;
}

.matching-row {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xs);
  flex-wrap: wrap;
}

.matching-prompt {
  min-width: 220px;
  font-weight: 600;
}

.matching-select {
  padding: 0.5rem;
  border: 2px solid var(--color-border);
  border-radius: 4px;
  font-size: 0.95rem;
  font-family: var(--font-body);
  flex: 1;
  min-width: 200px;
}

.matching-select.matching-correct {
  border-color: #2e7d32;
  background-color: #e8f5e9;
}

.matching-select.matching-incorrect {
  border-color: #c62828;
  background-color: #fce4ec;
}

/* --- Expandable Scenarios --- */
.scenario {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  margin-bottom: var(--space-sm);
  background-color: var(--color-card-bg);
}

.scenario summary {
  padding: var(--space-sm) var(--space-md);
  cursor: pointer;
  font-weight: 600;
  color: var(--color-heading);
  font-family: var(--font-heading);
}

.scenario summary:hover {
  background-color: var(--color-bg);
  border-radius: 6px;
}

.scenario .scenario-content {
  padding: 0 var(--space-md) var(--space-md);
}

/* --- Drag-and-Drop (free-form anatomy labeling) --- */
.drag-and-drop-container {
  margin: var(--space-md) 0;
}

.drag-and-drop-container .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 20px auto;
}

.drag-and-drop-container .image-container {
  position: relative;
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  border: 2px dashed transparent;
}

.drag-and-drop-container .image-container:hover {
  border-color: #007BFF;
}

.drag-and-drop-container #torso-image {
  width: 100%;
  height: auto;
}

.drag-and-drop-container .labels-container {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin: 20px 0;
  justify-content: center;
}

.drag-and-drop-container .label {
  color: white;
  font-size: 12px;
  cursor: grab;
  user-select: none;
  position: relative;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.drag-and-drop-container .label:active {
  cursor: grabbing;
}

#label-left-lung {
  background-color: #FF5733;
  border-radius: 50%;
  width: 100px;
  height: 200px;
}

#label-right-lung {
  background-color: #33B5FF;
  border-radius: 50%;
  width: 100px;
  height: 200px;
}

#label-heart {
  background-color: #FF33FF;
  clip-path: polygon(50% 0%, 100% 35%, 82% 100%, 50% 75%, 18% 100%, 0% 35%);
  width: 50px;
  height: 50px;
}

#label-trachea {
  background-color: #0f631e;
  width: 40px;
  height: 100px;
  border-radius: 5px;
  writing-mode: vertical-rl;
  text-orientation: upright;
  font-size: 10px;
}

#label-diaphragm {
  background-color: #FFC300;
  clip-path: path("M0,80 C0,0 120,0 120,80 Z");
  width: 120px;
  height: 80px;
  color: #FFFFFF;
  font-weight: bold;
}

#label-abdominal {
  background-color: #C700FF;
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  width: 120px;
  height: 200px;
}

#label-intercostal {
  background-color: #FF9933;
  width: 120px;
  height: 20px;
  border-radius: 5px;
}

.drag-and-drop-container .invisible {
  display: none;
}

.drag-and-drop-container .image-container .label {
  position: absolute;
}

/* --- Drag-and-Drop (match-to-zone, used in 2-6 assessment) --- */
.drag-drop-container {
  display: flex;
  gap: var(--space-md);
  margin: var(--space-md) 0;
}

.drag-labels {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  align-content: flex-start;
  min-width: 180px;
}

.drag-label {
  display: inline-block;
  padding: 0.4rem 0.8rem;
  background-color: var(--color-accent);
  color: #ffffff;
  border-radius: 4px;
  cursor: grab;
  font-size: 0.85rem;
  user-select: none;
  transition: opacity 0.2s ease;
}

.drag-label:active {
  cursor: grabbing;
}

.drag-label.placed {
  opacity: 0.4;
  cursor: default;
}

.drop-body-outline {
  position: relative;
  flex: 1;
  min-height: 400px;
  border: 2px dashed var(--color-border);
  border-radius: 6px;
  background-color: var(--color-card-bg);
}

.drop-zone {
  position: absolute;
  width: 140px;
  height: 32px;
  border: 2px dashed var(--color-border);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  color: var(--color-accent);
  background-color: rgba(255, 255, 255, 0.85);
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.drop-zone.drag-over {
  border-color: var(--color-accent);
  background-color: rgba(74, 85, 104, 0.1);
}

.drop-zone.correct {
  border-style: solid;
  border-color: var(--color-complete);
  background-color: #e8f5e9;
  color: var(--color-heading);
  font-weight: 600;
}

.drop-zone.incorrect {
  border-color: #c62828;
  background-color: #fce4ec;
}

/* --- Confidence Scale --- */
.confidence-scale {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  background-color: var(--color-card-bg);
}

.confidence-scale legend {
  font-weight: 600;
  font-family: var(--font-heading);
  color: var(--color-heading);
  margin-bottom: var(--space-sm);
}

.confidence-scale label {
  display: block;
  padding: 0.4rem 0.75rem;
  margin-bottom: 4px;
  cursor: pointer;
  border-radius: 4px;
}

.confidence-option {
  display: block;
  padding: 0.4rem 0.75rem;
  margin-bottom: 4px;
  cursor: pointer;
  border-radius: 4px;
}

.confidence-option:hover {
  background-color: var(--color-bg);
}

.confidence-option input[type="radio"] {
  margin-right: 0.5rem;
}

.confidence-thanks {
  margin-top: var(--space-sm);
  padding: var(--space-xs) var(--space-sm);
  background-color: #e8f5e9;
  color: #2e7d32;
  border-radius: 4px;
}

/* --- Lesson Images (full-width, inline) --- */
.lesson-image {
  margin: var(--space-md) 0;
}

.lesson-image img {
  width: 100%;
  height: auto;
  border-radius: 6px;
}

.lesson-image.lesson-image-sm {
  max-width: 480px;
}


.lesson-image .image-caption {
  font-size: 0.85rem;
  color: var(--color-accent);
  text-align: center;
  margin-top: var(--space-xs);
}

/* --- Image Gallery --- */
.image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: var(--space-sm);
  margin: var(--space-md) 0;
}

.image-gallery figure {
  margin: 0;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  overflow: hidden;
  background-color: var(--color-card-bg);
}

.image-gallery img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.image-gallery figcaption {
  padding: var(--space-xs) var(--space-sm);
  font-size: 0.85rem;
  color: var(--color-accent);
  text-align: center;
}

.lesson-img {
  width: 100%;
  border-radius: 6px;
  margin: var(--space-md) 0;
}

/* --- Reflection / Open-Ended --- */
/* --- PDF / Article Embed --- */
.pdf-embed {
  margin: var(--space-md) 0;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  overflow: hidden;
}

.pdf-embed iframe,
.pdf-embed object {
  width: 100%;
  height: 85vh;
  border: none;
}

.reflection {
  margin: var(--space-md) 0;
}

.reflection-note {
  font-size: 0.9rem;
  color: var(--color-text-muted, #666);
  font-style: italic;
  margin-bottom: var(--space-xs);
}

.reflection textarea {
  width: 100%;
  min-height: 120px;
  padding: var(--space-sm);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  resize: vertical;
  color: var(--color-text);
  background-color: var(--color-card-bg);
}

.reflection textarea:focus {
  outline: 2px solid var(--color-accent);
  border-color: var(--color-accent);
}

.example-toggle {
  margin-top: var(--space-xs);
}

.example-answer {
  margin-top: var(--space-sm);
  padding: var(--space-sm);
  background-color: #e8f5e9;
  border-radius: 6px;
  font-size: 0.95rem;
}

/* --- Comparison Table --- */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-md) 0;
}

.comparison-table th,
.comparison-table td {
  border: 1px solid var(--color-border);
  padding: var(--space-sm);
  text-align: left;
  vertical-align: top;
}

.comparison-table th {
  background-color: var(--color-heading);
  color: #ffffff;
  font-family: var(--font-heading);
  font-weight: 600;
}

.comparison-table td {
  background-color: var(--color-card-bg);
}

/* --- Steps Grid (compact two-column stepped instructions) --- */
.steps-grid {
  background-color: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 var(--space-lg);
}

.steps-grid h4 {
  margin-top: var(--space-sm);
  margin-bottom: 0.25em;
}

.steps-grid h4:first-child {
  margin-top: 0;
}

.steps-grid .steps-col:first-child {
  border-right: 1px solid var(--color-border);
  padding-right: var(--space-md);
}

.steps-grid ul {
  margin-top: 0.25em;
  margin-bottom: 0.5em;
}

@media (max-width: 768px) {
  .steps-grid {
    grid-template-columns: 1fr;
  }
  .steps-grid .steps-col:first-child {
    border-right: none;
    border-bottom: 1px solid var(--color-border);
    padding-right: 0;
    padding-bottom: var(--space-sm);
    margin-bottom: var(--space-sm);
  }
}

/* --- Teaching Prompts List --- */
.teaching-prompts {
  background-color: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
  margin-bottom: var(--space-sm);
}

.teaching-prompts h3 {
  margin-top: 0;
}

/* --- Equation Highlight --- */
.equation-highlight {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  padding: var(--space-lg) var(--space-md);
  margin: var(--space-lg) 0;
  background: linear-gradient(135deg, #f0f4ff 0%, #fff5f0 100%);
  border-radius: 10px;
  border: 2px solid var(--color-border);
}

.eq-result {
  color: #2b6cb0;
}

.eq-operator {
  color: var(--color-accent);
  margin: 0 0.3em;
}

.eq-potential {
  color: #2f855a;
}

.eq-interference {
  color: #c53030;
}

/* --- Self 1 / Self 2 Comparison Cards --- */
.self-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin: var(--space-lg) 0;
}

.self-card {
  border-radius: 8px;
  padding: var(--space-md) var(--space-lg);
}

.self-card h3 {
  margin-top: 0;
}

.self-card-one {
  background: #fff0f0;
  border-left: 4px solid #c53030;
}

.self-card-two {
  background: #f0faf4;
  border-left: 4px solid #2f855a;
}

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

/* --- Featured Quote --- */
.featured-quote {
  background: linear-gradient(135deg, #f7f8fc 0%, #fdf8f4 100%);
  border-left: 4px solid var(--color-accent);
  border-radius: 0 8px 8px 0;
  padding: var(--space-md) var(--space-lg);
  margin: var(--space-lg) 0;
  font-size: 1.15rem;
  font-style: italic;
  line-height: 1.7;
}

.featured-quote cite {
  display: block;
  margin-top: var(--space-sm);
  font-size: 0.95rem;
  font-style: normal;
  color: var(--color-accent);
}

/* --- Reflection Pair (side-by-side textareas) --- */
.reflection-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}

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

.btn-show-example {
  margin-top: var(--space-sm);
}

/* --- Example Answers (two-column reveal) --- */
.example-answers {
  background-color: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: var(--space-md) var(--space-lg);
  margin-top: var(--space-md);
}

.example-answers-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.example-answers-columns h3 {
  margin-top: 0;
}

.example-answers-columns ul {
  padding-left: 1.2em;
}

.example-answers-columns li {
  margin-bottom: 0.35em;
}

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

/* --- Thought Bubble variant for example answers --- */
.thought-bubble {
  position: relative;
  background-color: #f0f4ff;
  border: 2px solid #b0c4de;
  border-radius: 24px;
  padding: var(--space-md) var(--space-lg);
  margin-top: var(--space-lg);
}

.thought-bubble::before,
.thought-bubble::after {
  content: "";
  position: absolute;
  background-color: #f0f4ff;
  border: 2px solid #b0c4de;
  border-radius: 50%;
}

.thought-bubble::before {
  width: 28px;
  height: 28px;
  bottom: -20px;
  left: 40px;
}

.thought-bubble::after {
  width: 16px;
  height: 16px;
  bottom: -38px;
  left: 30px;
}

/* --- Centering Cards (Down / Up) --- */
.centering-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin: var(--space-lg) 0;
}

.centering-card {
  border-radius: 8px;
  padding: var(--space-md) var(--space-lg);
}

.centering-card h3 {
  margin-top: 0;
}

.centering-card ol {
  padding-left: 1.4em;
}

.centering-card li {
  margin-bottom: 0.4em;
}

.centering-use {
  font-style: italic;
  margin-bottom: 0.25em;
}

.centering-credit {
  font-size: 0.9rem;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.centering-down {
  background: #f0f4ff;
  border-left: 4px solid #2b6cb0;
}

.centering-up {
  background: #fff9f0;
  border-left: 4px solid #c05621;
}

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

/* --- Teaching Styles Comparison --- */
.teaching-styles {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: var(--space-md);
  align-items: start;
  margin: var(--space-lg) 0;
}

.style-card {
  border-radius: 8px;
  padding: var(--space-md) var(--space-lg);
}

.style-card h3 {
  margin-top: 0;
}

.style-a {
  background: #fff0f0;
  border-top: 4px solid #c53030;
}

.style-b {
  background: #f0faf4;
  border-top: 4px solid #2f855a;
}

.style-cues {
  font-style: italic;
  color: var(--color-accent);
  border-left: 3px solid var(--color-border);
  padding-left: var(--space-sm);
  margin-bottom: var(--space-sm);
}

.style-vs {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-accent);
  align-self: center;
  text-align: center;
}

@media (max-width: 768px) {
  .teaching-styles {
    grid-template-columns: 1fr;
  }
  .style-vs {
    text-align: left;
  }
}

/* --- Scenario Comparison (Style A vs B side-by-side) --- */
.scenario-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-top: var(--space-sm);
}

.scenario-style {
  border-radius: 6px;
  padding: var(--space-sm) var(--space-md);
}

.scenario-style h4 {
  margin-top: 0;
}

.scenario-style-a {
  background: #fff8f8;
  border-top: 3px solid #c53030;
}

.scenario-style-b {
  background: #f5fbf7;
  border-top: 3px solid #2f855a;
}

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