/* About English Idioms - Modern High-Performance Design System */
:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --accent: #f59e0b;
  --accent-light: #fef3c7;
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --bg-subtle: #f1f5f9;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --max-w: 1200px;
}

[data-theme="dark"] {
  --primary: #3b82f6;
  --primary-hover: #60a5fa;
  --primary-light: #1e293b;
  --accent: #fbbf24;
  --accent-light: #292524;
  --bg-page: #0b0f19;
  --bg-card: #131b2e;
  --bg-subtle: #1e293b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --border: #23324d;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.5);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.5);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.65;
  transition: background-color 0.25s ease, color 0.25s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  width: 100%;
}

/* Header & Nav */
header.site-header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-main);
  text-decoration: none;
}

.brand-badge {
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #fff;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 800;
  letter-spacing: 0.05em;
}

nav.main-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

nav.main-nav a {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
}

nav.main-nav a:hover, nav.main-nav a.active {
  color: var(--primary);
  text-decoration: none;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.theme-toggle-btn {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  color: var(--text-main);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
  font-size: 1.1rem;
}

.theme-toggle-btn:hover {
  background: var(--border);
}

/* Hero Section */
.hero-section {
  padding: 3.5rem 0 2.5rem;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, var(--primary-light) 0%, transparent 70%);
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 0.35rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-main);
}

.hero-highlight {
  background: linear-gradient(135deg, #2563eb, #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 650px;
  margin: 0 auto 2rem;
}

/* Daily Idiom Card */
.daily-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--primary);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 0 auto 2.5rem;
  max-width: 800px;
  text-align: left;
  box-shadow: var(--shadow-md);
}

.daily-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
}

.daily-tag {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-light);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
}

.daily-title {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.daily-meaning {
  font-size: 1.05rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.daily-example {
  background: var(--bg-subtle);
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  font-style: italic;
  font-size: 0.95rem;
  color: var(--text-main);
}

/* Search Bar & Controls */
.search-container {
  max-width: 720px;
  margin: 0 auto 1.5rem;
  position: relative;
}

.search-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.search-input {
  width: 100%;
  padding: 1rem 1.25rem 1rem 3.25rem;
  font-size: 1.1rem;
  border: 2px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--bg-card);
  color: var(--text-main);
  box-shadow: var(--shadow-md);
  transition: all 0.2s ease;
  outline: none;
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.15);
}

.search-icon {
  position: absolute;
  left: 1.25rem;
  color: var(--text-muted);
  font-size: 1.25rem;
  pointer-events: none;
}

.clear-search-btn {
  position: absolute;
  right: 1.25rem;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.25rem;
  cursor: pointer;
  display: none;
}

/* Category Filters */
.filter-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2.5rem;
}

.filter-pill {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 0.45rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.filter-pill:hover, .filter-pill.active {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

/* Idioms Grid */
.idioms-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3.5rem;
}

.idiom-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  display: flex;
  flex-direction: column;
}

.idiom-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);
}

.difficulty-badge {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
}

.diff-beginner {
  background: #dcfce7;
  color: #15803d;
}

.diff-intermediate {
  background: #e0f2fe;
  color: #0369a1;
}

.diff-advanced {
  background: #fef3c7;
  color: #b45309;
}

[data-theme="dark"] .diff-beginner { background: #14532d; color: #86efac; }
[data-theme="dark"] .diff-intermediate { background: #0c4a6e; color: #7dd3fc; }
[data-theme="dark"] .diff-advanced { background: #78350f; color: #fde68a; }

.card-category {
  font-size: 0.82rem;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.card-meaning {
  font-size: 0.95rem;
  color: var(--text-main);
  margin-bottom: 1rem;
  flex-grow: 1;
}

.card-examples {
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
  padding: 0.75rem;
  margin-bottom: 1rem;
}

.card-examples p {
  font-size: 0.88rem;
  font-style: italic;
  color: var(--text-muted);
}

.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
}

.action-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
}

.action-btn:hover {
  background: var(--bg-subtle);
  color: var(--primary);
}

/* Editorial Article Layout (Pillars) */
.article-header {
  padding: 3.5rem 0 2rem;
  background: radial-gradient(circle at 50% 0%, var(--primary-light) 0%, transparent 70%);
  border-bottom: 1px solid var(--border);
  text-align: center;
}

.breadcrumbs {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.breadcrumbs a {
  color: var(--text-muted);
}

.article-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.article-container {
  max-width: 860px;
  margin: 3rem auto;
  padding: 0 1.5rem;
}

.article-content {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--text-main);
}

.article-content h2 {
  font-size: 1.75rem;
  font-weight: 800;
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border);
  color: var(--text-main);
}

.article-content h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  color: var(--text-main);
}

.article-content p {
  margin-bottom: 1.4rem;
}

.article-content blockquote {
  border-left: 4px solid var(--primary);
  background: var(--bg-card);
  padding: 1.25rem 1.5rem;
  margin: 1.75rem 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  box-shadow: var(--shadow-sm);
}

.article-content ul, .article-content ol {
  margin: 1.25rem 0 1.5rem 2rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

/* Comparison Tables */
.table-wrapper {
  overflow-x: auto;
  margin: 2rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

table.editorial-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
  background: var(--bg-card);
}

table.editorial-table th {
  background: var(--bg-subtle);
  padding: 0.9rem 1.2rem;
  font-weight: 700;
  border-bottom: 1px solid var(--border);
}

table.editorial-table td {
  padding: 0.9rem 1.2rem;
  border-bottom: 1px solid var(--border);
}

table.editorial-table tr:last-child td {
  border-bottom: none;
}

/* Callout Box */
.callout {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  padding: 1.5rem;
  border-radius: var(--radius-sm);
  margin: 2rem 0;
  box-shadow: var(--shadow-sm);
}

.callout-title {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  color: var(--accent);
}

/* Quiz Page Styles */
.quiz-wrapper {
  max-width: 720px;
  margin: 3rem auto;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

.quiz-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2rem;
}

.quiz-question-box {
  margin-bottom: 2rem;
}

.quiz-question-title {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.quiz-options-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.quiz-option-btn {
  background: var(--bg-subtle);
  border: 2px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  font-size: 1rem;
  text-align: left;
  color: var(--text-main);
  cursor: pointer;
  transition: all 0.2s ease;
}

.quiz-option-btn:hover {
  border-color: var(--primary);
  background: var(--bg-card);
}

.quiz-option-btn.correct {
  background: #dcfce7;
  border-color: #22c55e;
  color: #15803d;
}

.quiz-option-btn.incorrect {
  background: #fee2e2;
  border-color: #ef4444;
  color: #b91c1c;
}

/* Flashcards 3D Styles */
.flashcard-wrapper {
  max-width: 650px;
  margin: 3rem auto;
  perspective: 1000px;
}

.flashcard {
  width: 100%;
  min-height: 380px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  cursor: pointer;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2.5rem;
  text-align: center;
}

.flashcard.flipped {
  transform: rotateY(180deg);
}

.flashcard-front, .flashcard-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2.5rem;
}

.flashcard-back {
  transform: rotateY(180deg);
}

.flashcard-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 2rem;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
  border: none;
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
}

.btn-primary:hover {
  background: var(--primary-hover);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background: transparent;
  color: var(--text-main);
  border: 1px solid var(--border);
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-outline:hover {
  background: var(--bg-subtle);
  border-color: var(--primary);
}

/* Footer */
footer.site-footer {
  margin-top: auto;
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 3.5rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 2.5rem;
}

.footer-col h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text-main);
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 0.6rem;
}

.footer-col a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .header-inner {
    flex-wrap: wrap;
    height: auto;
    padding: 1rem 0;
    gap: 1rem;
  }
  nav.main-nav {
    order: 3;
    width: 100%;
    justify-content: space-around;
    padding-top: 0.5rem;
    border-top: 1px solid var(--border);
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .idioms-grid {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================
   IDIOM DEEP-DIVE ENHANCEMENTS (8-PART ANATOMY)
   ========================================================== */

.quick-ref-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  margin: 2rem 0 2.5rem;
  box-shadow: var(--shadow-md);
}

.quick-ref-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 1.25rem;
}

.ref-pill {
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.35rem 0.75rem;
  border-radius: 9999px;
  background: var(--bg-subtle);
  color: var(--text-muted);
}

.ref-pill-primary {
  background: var(--primary-light);
  color: var(--primary);
}

.quick-ref-meaning {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--text-main);
  margin-bottom: 1.25rem;
}

.quick-ref-dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

@media (max-width: 640px) {
  .quick-ref-dual-grid {
    grid-template-columns: 1fr;
  }
}

.dual-box {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  font-size: 0.95rem;
}

.dual-box strong {
  display: block;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.quick-ref-actions {
  display: flex;
  gap: 0.75rem;
  border-top: 1px solid var(--border);
  padding-top: 1.25rem;
}

/* ESL Dialogues */
.dialogue-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 1.75rem 0;
  box-shadow: var(--shadow-sm);
}

.dialogue-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.dialogue-context {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  font-style: italic;
}

.dialogue-script {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.dialogue-line {
  display: flex;
  gap: 1rem;
  font-size: 0.98rem;
  line-height: 1.5;
}

.speaker-tag {
  font-weight: 700;
  color: var(--text-main);
  min-width: 90px;
  flex-shrink: 0;
}

.speech-text {
  color: var(--text-main);
}

.speech-text em, .speech-text strong {
  background: var(--primary-light);
  color: var(--primary);
  padding: 0.1rem 0.3rem;
  border-radius: 4px;
  font-weight: 700;
  font-style: normal;
}

/* Learner Traps Box */
.traps-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin: 1.75rem 0;
}

.trap-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid #ef4444;
  border-radius: var(--radius-sm);
  padding: 1.25rem;
}

.trap-header {
  font-weight: 700;
  font-size: 1rem;
  color: #b91c1c;
  margin-bottom: 0.5rem;
}

.trap-examples {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  font-size: 0.92rem;
  margin-top: 0.5rem;
}

.trap-wrong {
  color: #dc2626;
  background: #fef2f2;
  padding: 0.35rem 0.65rem;
  border-radius: 4px;
}

.trap-right {
  color: #15803d;
  background: #f0fdf4;
  padding: 0.35rem 0.65rem;
  border-radius: 4px;
}

/* Interactive Mini-Quiz */
.mini-quiz-widget {
  background: var(--bg-card);
  border: 2px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
  margin: 2.5rem 0;
  box-shadow: var(--shadow-md);
}

.mini-quiz-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border);
  padding-bottom: 1rem;
  margin-bottom: 1.5rem;
}

.mini-quiz-badge {
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  background: var(--primary-light);
  color: var(--primary);
  padding: 0.3rem 0.6rem;
  border-radius: 4px;
}

.mini-quiz-q {
  font-weight: 700;
  font-size: 1.15rem;
  margin-bottom: 1rem;
}

.mini-quiz-options {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  margin-bottom: 1.25rem;
}

.mini-opt-btn {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  text-align: left;
  font-size: 0.95rem;
  cursor: pointer;
  color: var(--text-main);
  transition: all 0.2s;
}

.mini-opt-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: var(--bg-card);
}

.mini-opt-btn.correct {
  background: #dcfce7 !important;
  border-color: #22c55e !important;
  color: #15803d !important;
  font-weight: 700;
}

.mini-opt-btn.incorrect {
  background: #fee2e2 !important;
  border-color: #ef4444 !important;
  color: #991b1b !important;
}

.mini-feedback {
  display: none;
  font-size: 0.92rem;
  line-height: 1.5;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  margin-top: 0.5rem;
}

.mini-feedback.show {
  display: block;
}

.mini-feedback.correct-fb {
  background: #f0fdf4;
  color: #166534;
  border: 1px solid #bbf7d0;
}

.mini-feedback.incorrect-fb {
  background: #fef2f2;
  color: #991b1b;
  border: 1px solid #fecaca;
}

/* 3+1+1 Mesh Navigation */
.semantic-mesh-box {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
  margin: 3rem 0 1rem;
}

.mesh-title {
  font-size: 1.25rem;
  font-weight: 800;
  margin-bottom: 1.25rem;
  color: var(--text-main);
}

.mesh-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}

.mesh-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}

.mesh-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
  border-color: var(--primary);
}

.mesh-tag {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.35rem;
}

.mesh-label {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-main);
  margin-bottom: 0.35rem;
}

.mesh-desc {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.4;
}