:root {
  --primary: #1C3D5A;       /* Bleu foncé */
  --accent: #F58634;        /* Orange */
  --bg: #f8fafc;            /* Fond de page clair */
  --card: #ffffff;          /* Fond des conteneurs */
  --text: #475569;          /* Couleur de texte principale */
  --text-dark: #1C3D5A;     /* Texte plus prononcé */
  --border: #e2e8f0;        /* Bordures légères */
  --nav-bg: #f1f5f9;        /* Fond de la navigation */
  --success: #52B788;       /* Vert succès */
  --error: #ef4444;         /* Rouge erreur */
}

[data-theme="dark"] {
  --primary: #F58634;
  --accent: #1C3D5A;
  --bg: #0b0f19;
  --card: #1e293b;
  --text: #cbd5e1;
  --text-dark: #f8fafc;
  --border: #334155;
  --nav-bg: #111827;
}

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

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  padding: 20px 10px;
  line-height: 1.5;
}

.container {
  max-width: 900px;
  margin: auto;
  background: var(--card);
  border-radius: 12px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
  overflow: hidden;
  border: 1px solid var(--border);
}

/* Header */
header {
  background: var(--primary);
  color: #ffffff;
  padding: 30px 20px;
  text-align: center;
  position: relative;
  border-bottom: 3px solid var(--accent);
}

[data-theme="dark"] header {
  background: #111827;
  border-bottom: 3px solid var(--primary);
}

header h1 {
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 4px;
}

.subtitle {
  font-size: 0.95rem;
  opacity: 0.85;
}

.header-controls {
  position: absolute;
  top: 20px;
  right: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.85rem;
}

#themeToggle {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: white;
  padding: 6px 10px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s;
}

#themeToggle:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* Barre de recherche */
.search-container {
  padding: 15px 20px 0 20px;
}

#search {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text-dark);
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

#search:focus {
  outline: none;
  border-color: var(--accent);
}

/* Navigation */
nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 15px 20px;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
}

.nav-btn {
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card);
  color: var(--text-dark);
  font-weight: 500;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.2s;
}

.nav-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

nav button.active {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

/* Sections */
.section { 
  display: none; 
  padding: 30px 20px; 
  min-height: 450px; 
}
.section.active { 
  display: block; 
}

.section h2 {
  font-size: 1.4rem;
  color: var(--text-dark);
  margin-bottom: 20px;
  font-weight: 600;
}

/* Verbes List */
.verb-card {
  background: var(--bg);
  padding: 16px;
  margin-bottom: 12px;
  border-radius: 8px;
  border-left: 4px solid var(--accent);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 15px;
}

.verb-card strong {
  color: var(--text-dark);
  font-size: 1.1rem;
}

.verb-card small {
  color: var(--text);
  font-size: 0.9rem;
}

.mastery { 
  font-size: 0.85rem; 
  color: var(--text);
  background: var(--card);
  padding: 4px 8px;
  border-radius: 4px;
  border: 1px solid var(--border);
}

/* Boutons */
.btn-primary, .verb-card button, .quiz-container button {
  padding: 10px 20px;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: white;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-primary:hover, .verb-card button:hover {
  background: #d96e20;
}

.verb-card button {
  padding: 6px 12px;
  font-size: 0.85rem;
}

.action-container {
  display: flex;
  justify-content: center;
  margin-top: 25px;
}

/* Flashcards */
.card {
  width: 100%;
  max-width: 400px;
  height: 260px;
  margin: 20px auto;
  perspective: 1000px;
  cursor: pointer;
}
.card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.card.flipped .card-inner { transform: rotateY(180deg); }

.front, .back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 20px;
  text-align: center;
  border: 1px solid var(--border);
}
.front { 
  background: var(--primary); 
  color: white; 
}
.front h2 { color: white; font-size: 2rem; margin-bottom: 10px; }
.front p { font-size: 0.85rem; opacity: 0.7; }

.back { 
  background: var(--card); 
  color: var(--text-dark); 
  transform: rotateY(180deg); 
}
.back h2 { font-size: 1.6rem; margin-bottom: 10px; color: var(--accent); }
.back p { font-size: 1.1rem; margin-bottom: 20px; font-style: italic; }

/* Quiz & Options */
.quiz-container {
  text-align: center;
  max-width: 500px;
  margin: auto;
}
.quiz-container h3 {
  font-size: 1.3rem;
  margin-bottom: 20px;
  color: var(--text-dark);
}

.option {
  width: 100%;
  margin: 8px 0;
  padding: 14px;
  font-size: 1rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-dark);
  cursor: pointer;
  transition: all 0.2s;
  font-weight: 500;
}
.option:hover {
  border-color: var(--accent);
  background: var(--nav-bg);
}

#audioOptions {
  margin-top: 20px;
}

/* Zone de Matching Grille */
.matching-board {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  max-width: 600px;
  margin: 0 auto;
}

.matching-column {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.matching-item {
  background: var(--bg);
  border: 2px solid var(--border);
  padding: 15px;
  border-radius: 8px;
  text-align: center;
  font-weight: 600;
  color: var(--text-dark);
  cursor: pointer;
  user-select: none;
  transition: all 0.2s ease;
}

.matching-item:hover {
  border-color: var(--accent);
}

.matching-item.selected {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.matching-item.matched {
  background: var(--success);
  color: white;
  border-color: var(--success);
  cursor: default;
  opacity: 0.65;
}

.matching-item.error {
  background: var(--error);
  color: white;
  border-color: var(--error);
}

.status-message {
  text-align: center;
  padding: 40px;
  color: var(--text);
  font-style: italic;
}

/* Stats Progress Bar */
.progress-bar-container {
  height: 16px;
  background: var(--nav-bg);
  border-radius: 8px;
  overflow: hidden;
  margin: 15px 0 25px 0;
  border: 1px solid var(--border);
}
.progress-bar {
  height: 100%;
  background: var(--accent);
  transition: width 0.4s ease;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 15px;
  margin-top: 15px;
}
.stat-box {
  background: var(--bg);
  padding: 15px;
  border-radius: 8px;
  border: 1px solid var(--border);
  text-align: center;
}
.stat-box span { display: block; font-size: 0.85rem; color: var(--text); }
.stat-box strong { font-size: 1.4rem; color: var(--text-dark); }

/* Footer */
footer {
  padding: 20px;
  text-align: center;
  background: var(--nav-bg);
  border-top: 1px solid var(--border);
  color: var(--text);
  font-size: 0.95rem;
}
.footer-stats strong {
  color: var(--text-dark);
}