/* ============================================================
   French Vocabulary Trainer -- Stylesheet
   ============================================================ */

:root {
  /* Warm, French-inspired palette */
  --color-bg: #f8f6f2;
  --color-surface: #ffffff;
  --color-primary: #2d5a8a;
  --color-primary-light: #4a7ab5;
  --color-primary-dark: #1e3f63;
  --color-accent: #c4463a;
  --color-success: #3a7d44;
  --color-warning: #d4a843;
  --color-danger: #b5342b;
  --color-text: #2c2c2c;
  --color-text-light: #6b6b6b;
  --color-border: #e0dcd7;

  /* Leitner box colors */
  --box-1: #c4463a;
  --box-2: #d4a843;
  --box-3: #4a7ab5;
  --box-4: #3a7d44;
  --box-5: #7b6baf;
  --box-unseen: #b0aaa0;

  /* Typography */
  --font-body: Georgia, 'Times New Roman', serif;
  --font-ui: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;

  /* Card */
  --radius: 10px;
  --shadow: 0 2px 8px rgba(0,0,0,0.07);
  --shadow-lg: 0 4px 20px rgba(0,0,0,0.10);
}


/* --- Reset & Base -------------------------------------------------------- */

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

body {
  font-family: var(--font-ui);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
}

a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3 { font-family: var(--font-body); font-weight: 600; line-height: 1.3; }
h1 { font-size: 1.75rem; }
h2 { font-size: 1.3rem; }
h3 { font-size: 1.1rem; }

.container { max-width: 800px; margin: 0 auto; padding: var(--space-lg); }


/* --- Navigation ---------------------------------------------------------- */

.nav {
  background: var(--color-primary-dark);
  color: white;
  padding: 0 var(--space-lg);
}
.nav-inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  height: 52px;
}
.nav-brand {
  font-family: var(--font-body);
  font-size: 1.2rem;
  font-weight: 700;
  color: white;
  letter-spacing: 0.02em;
}
.nav-brand:hover { text-decoration: none; opacity: 0.9; }
.nav-links { display: flex; gap: var(--space-xs); flex: 1; }
.nav-link {
  color: rgba(255,255,255,0.8);
  padding: var(--space-xs) var(--space-sm);
  border-radius: 6px;
  font-size: 0.875rem;
  transition: background 0.15s, color 0.15s;
}
.nav-link:hover { background: rgba(255,255,255,0.12); color: white; text-decoration: none; }
.nav-user { display: flex; align-items: center; gap: var(--space-sm); }
.nav-username { color: rgba(255,255,255,0.7); font-size: 0.85rem; }
.nav-logout {
  background: none; border: 1px solid rgba(255,255,255,0.3);
  color: rgba(255,255,255,0.8); border-radius: 6px;
  padding: 4px 10px; font-size: 0.8rem; cursor: pointer;
  transition: background 0.15s;
}
.nav-logout:hover { background: rgba(255,255,255,0.12); color: white; }
.inline { display: inline; }


/* --- Cards & Sections ---------------------------------------------------- */

.card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
}
.card h2 { margin-bottom: var(--space-sm); }
.card-subtitle { color: var(--color-text-light); margin-bottom: var(--space-md); }
.card-danger { border-left: 4px solid var(--color-danger); }

.page-header { margin-bottom: var(--space-xl); }
.page-header h1 { margin-bottom: var(--space-xs); }
.subtitle { color: var(--color-text-light); font-size: 1rem; }
.muted { color: var(--color-text-light); font-size: 0.875rem; }


/* --- Buttons ------------------------------------------------------------- */

.btn {
  display: inline-block;
  font-family: var(--font-ui);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 10px 24px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  text-align: center;
  transition: background 0.15s, transform 0.1s;
  text-decoration: none;
  line-height: 1.4;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn-primary { background: var(--color-primary); color: white; }
.btn-primary:hover { background: var(--color-primary-light); }
.btn-secondary { background: var(--color-border); color: var(--color-text); }
.btn-secondary:hover { background: #d0ccc6; }
.btn-danger { background: var(--color-danger); color: white; }
.btn-danger:hover { background: #9e2d25; }

.btn-full { width: 100%; }
.btn-large { font-size: 1.1rem; padding: 14px 32px; }
.btn-sm { font-size: 0.85rem; padding: 6px 16px; }


/* --- Forms --------------------------------------------------------------- */

label {
  display: block;
  font-weight: 500;
  margin-bottom: var(--space-xs);
  font-size: 0.9rem;
}
input[type="text"],
input[type="password"],
input[type="number"] {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--color-border);
  border-radius: 8px;
  font-size: 1rem;
  font-family: var(--font-ui);
  margin-bottom: var(--space-md);
  transition: border-color 0.15s;
}
input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(45,90,138,0.15);
}
.input-sm { width: auto; margin-bottom: 0; }
.inline-form { display: flex; align-items: center; gap: var(--space-sm); }


/* --- Alerts -------------------------------------------------------------- */

.alert {
  padding: var(--space-sm) var(--space-md);
  border-radius: 8px;
  margin-bottom: var(--space-md);
  font-size: 0.9rem;
}
.alert-error { background: #fde8e8; color: var(--color-danger); border: 1px solid #f5c6c3; }
.alert-success { background: #e8f5e9; color: var(--color-success); border: 1px solid #c3e6cb; }


/* --- Auth Pages ---------------------------------------------------------- */

.auth-page {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 80vh;
}
.auth-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: var(--space-2xl);
  width: 100%;
  max-width: 400px;
  text-align: center;
}
.auth-card h1 {
  font-family: var(--font-body);
  font-size: 2rem;
  color: var(--color-primary-dark);
  margin-bottom: var(--space-xs);
}
.auth-subtitle {
  color: var(--color-text-light);
  margin-bottom: var(--space-xl);
}
.auth-form { text-align: left; margin-top: var(--space-lg); }
.auth-form .btn { margin-top: var(--space-sm); }
.auth-switch { margin-top: var(--space-lg); font-size: 0.9rem; color: var(--color-text-light); }


/* --- Progress Bars ------------------------------------------------------- */

.progress-bar {
  height: 10px;
  background: #eae6e0;
  border-radius: 5px;
  overflow: hidden;
  margin: var(--space-sm) 0;
}
.progress-bar-sm { height: 6px; }
.progress-fill {
  height: 100%;
  background: var(--color-primary);
  border-radius: 5px;
  transition: width 0.4s ease;
}
.fill-mastered { background: var(--box-5); }


/* --- Dashboard ----------------------------------------------------------- */

.quick-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}
.action-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: var(--space-lg);
  text-align: center;
  transition: transform 0.15s, box-shadow 0.15s;
  color: var(--color-text);
}
.action-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  text-decoration: none;
}
.action-primary { background: var(--color-primary); color: white; }
.action-primary:hover { background: var(--color-primary-light); color: white; }
.action-primary .action-detail { color: rgba(255,255,255,0.8); }
.action-icon { font-size: 2rem; margin-bottom: var(--space-sm); }
.action-label { font-weight: 600; font-size: 1.1rem; }
.action-detail { font-size: 0.85rem; color: var(--color-text-light); margin-top: var(--space-xs); }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}
.stat-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: var(--space-lg);
  text-align: center;
}
.stat-value { font-size: 2rem; font-weight: 700; color: var(--color-primary-dark); }
.stat-label { font-size: 0.85rem; color: var(--color-text-light); margin-top: var(--space-xs); }


/* --- Leitner Box Distribution -------------------------------------------- */

.box-distribution { display: flex; flex-direction: column; gap: var(--space-sm); }
.box-row {
  display: grid;
  grid-template-columns: 50px 80px 1fr 40px;
  align-items: center;
  gap: var(--space-sm);
}
.box-label { font-weight: 600; font-size: 0.85rem; }
.box-name { font-size: 0.8rem; color: var(--color-text-light); }
.box-bar-track { height: 8px; background: #eae6e0; border-radius: 4px; overflow: hidden; }
.box-bar-fill { height: 100%; border-radius: 4px; transition: width 0.4s ease; }
.box-count { font-size: 0.85rem; text-align: right; font-weight: 500; }

.box-color-1, .box-color-1 { color: var(--box-1); }
.box-color-2 { color: var(--box-2); }
.box-color-3 { color: var(--box-3); }
.box-color-4 { color: var(--box-4); }
.box-color-5 { color: var(--box-5); }
.box-color-unseen { color: var(--box-unseen); }

.box-bar-fill.box-color-1 { background: var(--box-1); }
.box-bar-fill.box-color-2 { background: var(--box-2); }
.box-bar-fill.box-color-3 { background: var(--box-3); }
.box-bar-fill.box-color-4 { background: var(--box-4); }
.box-bar-fill.box-color-5 { background: var(--box-5); }


/* --- Lesson list --------------------------------------------------------- */

.lesson-list { display: flex; flex-direction: column; gap: var(--space-sm); }
.lesson-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--color-border);
}
.lesson-row:last-child { border-bottom: none; }
.lesson-locked { opacity: 0.5; }
.lesson-info { display: flex; align-items: center; gap: var(--space-sm); }
.lesson-num { font-weight: 600; color: var(--color-text-light); }
.lesson-title { font-weight: 500; }
.lesson-bar { display: flex; align-items: center; gap: var(--space-sm); min-width: 160px; }

.badge {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.03em;
}
.badge-complete { background: #e8f5e9; color: var(--color-success); }
.badge-current { background: #e3f2fd; color: var(--color-primary); }
.badge-locked { background: #f0ece6; color: var(--box-unseen); }


/* --- Lesson Cards (overview page) ---------------------------------------- */

.lesson-cards { display: flex; flex-direction: column; gap: var(--space-md); }
.lesson-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: var(--space-lg);
}
.lesson-card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-sm); }
.lesson-card-header h2 { margin-bottom: 0; }
.lesson-desc { color: var(--color-text-light); font-size: 0.9rem; margin-bottom: var(--space-sm); }


/* --- Word Browse Cards --------------------------------------------------- */

.browse-words {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}
.browse-word-card {
  background: var(--color-surface);
  border-radius: 8px;
  box-shadow: var(--shadow);
  padding: var(--space-md) var(--space-lg);
}
.browse-word-top {
  display: flex;
  align-items: baseline;
  gap: var(--space-sm);
  margin-bottom: var(--space-xs);
}
.browse-word-french {
  font-family: var(--font-body);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--color-primary-dark);
}
.browse-word-gender {
  font-size: 0.85rem;
  color: var(--color-text-light);
}
.audio-btn {
  background: none;
  border: 1.5px solid var(--color-primary);
  color: var(--color-primary);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  font-size: 0.7rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  transition: background 0.15s, color 0.15s;
  flex-shrink: 0;
}
.audio-btn:hover {
  background: var(--color-primary);
  color: white;
}
.audio-btn-lg {
  width: 36px;
  height: 36px;
  font-size: 0.85rem;
  margin: var(--space-xs) 0;
}
.browse-word-pronunciation {
  font-size: 0.9rem;
  color: var(--color-text-light);
  font-style: italic;
  padding: var(--space-xs) var(--space-sm);
  background: var(--color-bg);
  border-radius: 4px;
  display: inline-block;
  margin-bottom: var(--space-xs);
}
.browse-word-english {
  font-size: 1rem;
  font-weight: 500;
}


/* --- Word Browse Table (legacy) ----------------------------------------- */

.word-table { font-size: 0.9rem; }
.word-header {
  display: grid;
  grid-template-columns: 50px 1fr 1fr 60px 1fr;
  gap: var(--space-sm);
  font-weight: 600;
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-border);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-light);
}
.word-row {
  display: grid;
  grid-template-columns: 50px 1fr 1fr 60px 1fr;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid #f0ece6;
  align-items: center;
}
.word-row:last-child { border-bottom: none; }

.box-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 2px 6px;
  border-radius: 4px;
  text-align: center;
  background: currentColor;
}
.box-badge { color: white; }
.box-color-1 .box-badge, .box-badge.box-color-1 { background: var(--box-1); color: white; }
.box-badge.box-color-2 { background: var(--box-2); color: white; }
.box-badge.box-color-3 { background: var(--box-3); color: white; }
.box-badge.box-color-4 { background: var(--box-4); color: white; }
.box-badge.box-color-5 { background: var(--box-5); color: white; }
.box-badge.box-color-unseen { background: var(--box-unseen); color: white; }


/* --- Flashcard ----------------------------------------------------------- */

.study-page { display: flex; justify-content: center; padding-top: var(--space-xl); }
#study-area, #quiz-area { width: 100%; max-width: 500px; }

.study-start { text-align: center; }
.study-start h1 { margin-bottom: var(--space-sm); }

.card-breakdown {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-md);
  margin: var(--space-xl) 0;
  flex-wrap: wrap;
}
.breakdown-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.breakdown-count { font-size: 1.5rem; font-weight: 700; color: var(--color-primary-dark); }
.breakdown-new .breakdown-count { color: var(--color-success); }
.breakdown-reinforce .breakdown-count { color: var(--color-warning); }
.breakdown-label { font-size: 0.8rem; color: var(--color-text-light); }
.breakdown-total { font-size: 1.1rem; font-weight: 500; }

.flashcard {
  background: var(--color-surface);
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
  padding: var(--space-2xl) var(--space-xl);
  text-align: center;
  position: relative;
}
.card-counter {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  font-size: 0.85rem;
  color: var(--color-text-light);
}
.card-tag {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: var(--space-md);
  letter-spacing: 0.04em;
}
.tag-new { background: #e8f5e9; color: var(--color-success); }
.tag-reinforce { background: #fff8e1; color: #b8860b; }
.tag-quiz { background: #e3f2fd; color: var(--color-primary); }

.card-french {
  font-family: var(--font-body);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  margin: var(--space-md) 0;
}
.card-gender {
  font-size: 0.9rem;
  color: var(--color-text-light);
  margin-bottom: var(--space-sm);
}
.card-notes {
  font-size: 0.85rem;
  color: var(--color-text-light);
  font-style: italic;
  margin-bottom: var(--space-lg);
  padding: var(--space-sm) var(--space-md);
  background: #f8f6f2;
  border-radius: 6px;
  display: inline-block;
}

.answer-input {
  text-align: center;
  font-size: 1.2rem;
  padding: 14px;
  max-width: 320px;
  margin: var(--space-md) auto;
}
.card-actions {
  display: flex;
  justify-content: center;
  gap: var(--space-sm);
  margin-top: var(--space-md);
}


/* --- Result States ------------------------------------------------------- */

.result-correct { border-top: 4px solid var(--color-success); }
.result-wrong { border-top: 4px solid var(--color-accent); }

.result-text {
  font-size: 1.3rem;
  font-weight: 700;
  margin: var(--space-md) 0;
}
.result-text.correct { color: var(--color-success); }
.result-text.wrong { color: var(--color-accent); }

.result-answer {
  font-size: 1.1rem;
  font-weight: 500;
  margin-bottom: var(--space-sm);
}
.box-change {
  font-size: 0.9rem;
  color: var(--color-text-light);
  margin-bottom: var(--space-lg);
}
.box-change.demoted { color: var(--color-accent); }


/* --- Session Summary ----------------------------------------------------- */

.session-summary {
  background: var(--color-surface);
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
  padding: var(--space-2xl) var(--space-xl);
  text-align: center;
}
.session-summary h2 { margin-bottom: var(--space-lg); }
.session-summary h3 { margin-bottom: var(--space-sm); margin-top: var(--space-lg); }

.summary-score { margin-bottom: var(--space-lg); }
.score-big {
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  line-height: 1;
}
.score-detail { color: var(--color-text-light); margin-top: var(--space-xs); }

.summary-stats { display: flex; justify-content: center; gap: var(--space-lg); margin-bottom: var(--space-lg); }
.summary-stat { font-weight: 600; font-size: 0.95rem; }
.stat-good { color: var(--color-success); }
.stat-bad { color: var(--color-accent); }

.summary-boxes { text-align: left; margin: var(--space-lg) 0; }

.lesson-complete-banner {
  background: #e8f5e9;
  border: 2px solid var(--color-success);
  border-radius: var(--radius);
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
}
.lesson-complete-banner h3 { color: var(--color-success); margin-bottom: var(--space-sm); }

.lesson-progress-summary { margin: var(--space-lg) 0; }
.mastery-summary { margin: var(--space-lg) 0; }
.motivation {
  font-style: italic;
  color: var(--color-text-light);
  margin: var(--space-lg) 0;
}

.summary-actions { display: flex; justify-content: center; gap: var(--space-md); margin-top: var(--space-xl); }


/* --- Rules --------------------------------------------------------------- */

.rules-list { padding-left: var(--space-lg); }
.rules-list li {
  padding: var(--space-sm) 0;
  border-bottom: 1px solid #f0ece6;
  line-height: 1.6;
}
.rules-list li:last-child { border-bottom: none; }


/* --- Sub-lesson Grid ----------------------------------------------------- */

.sub-lesson-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-top: var(--space-lg);
}
.sub-lesson-card {
  background: var(--color-bg);
  border-radius: 8px;
  padding: var(--space-md);
  border: 1px solid var(--color-border);
}
.sub-lesson-card.sub-lesson-complete {
  border-color: var(--color-success);
  background: #f7fcf8;
}
.sub-lesson-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-xs);
}
.sub-lesson-header h3 { margin-bottom: 0; font-size: 1rem; }

/* Lesson instruction paragraph */
.lesson-instruction {
  color: var(--color-text);
  line-height: 1.7;
  margin-bottom: var(--space-md);
  font-size: 0.95rem;
}
.sub-lesson-card .btn { margin-top: var(--space-sm); }

/* Sub-lesson list (lessons overview page) */
.sub-lesson-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-top: var(--space-md);
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-sm);
}
.sub-lesson-row {
  display: grid;
  grid-template-columns: 1fr 160px auto;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid #f0ece6;
}
.sub-lesson-row:last-child { border-bottom: none; }
.sub-lesson-info { display: flex; align-items: center; gap: var(--space-sm); }
.sub-lesson-title { font-weight: 500; font-size: 0.9rem; }
.sub-lesson-bar { display: flex; align-items: center; gap: var(--space-xs); }
.sub-lesson-actions { display: flex; gap: var(--space-xs); }

/* Sub-lesson completion banner */
.sub-lesson-complete-banner {
  background: #e8f5e9;
  border: 1px solid var(--color-success);
  border-radius: var(--radius);
  padding: var(--space-md);
  margin: var(--space-md) 0;
}
.sub-lesson-complete-banner h3 { color: var(--color-success); margin-bottom: var(--space-xs); }

/* Study focus label */
.study-focus {
  font-family: var(--font-body);
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--color-primary-dark);
  margin-top: var(--space-xs);
}


/* --- Guide Page ---------------------------------------------------------- */

.guide-page .card { margin-bottom: var(--space-lg); }
.guide-page .card p { margin-bottom: var(--space-sm); line-height: 1.7; }

.guide-boxes {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  margin: var(--space-md) 0;
  padding: var(--space-md);
  background: var(--color-bg);
  border-radius: 8px;
}
.guide-box-row {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-xs) 0;
}
.guide-box-row .box-label { min-width: 52px; text-align: center; }
.guide-box-desc { font-size: 0.9rem; }

.guide-list {
  padding-left: var(--space-lg);
  margin: var(--space-sm) 0;
}
.guide-list li {
  padding: var(--space-xs) 0;
  line-height: 1.6;
}


/* --- Responsive ---------------------------------------------------------- */

@media (max-width: 768px) {
  .nav-inner { gap: var(--space-sm); }
  .nav-links { flex-wrap: wrap; gap: 2px; }
  .nav-link { font-size: 0.8rem; padding: 2px 6px; }
  .nav-username { display: none; }

  .container { padding: var(--space-md); }

  .quick-actions { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr; }

  .word-header, .word-row {
    grid-template-columns: 40px 1fr 1fr;
  }
  .word-col-gender, .word-col-notes { display: none; }

  .box-row { grid-template-columns: 40px 70px 1fr 35px; }

  .card-french { font-size: 2rem; }
  .flashcard { padding: var(--space-xl) var(--space-md); }

  .lesson-row { flex-direction: column; align-items: flex-start; gap: var(--space-xs); }
  .lesson-bar { min-width: 100%; }

  .sub-lesson-grid { grid-template-columns: 1fr; }
  .sub-lesson-row { grid-template-columns: 1fr; gap: var(--space-xs); }
  .sub-lesson-bar { min-width: 100%; }
}