:root {
  --beige: #f4ead8;
  --beige-fonce: #d8c3a5;
  --marron: #4a3428;
  --texte: #2b2520;
  --blanc: #ffffff;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: var(--beige);
  color: var(--texte);
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 25px 8%;
}

.logo {
  font-size: 1.7rem;
  font-weight: bold;
  color: var(--marron);
}

.menu a {
  margin-left: 20px;
  text-decoration: none;
  color: var(--marron);
  font-weight: bold;
}

.hero {
  background: linear-gradient(135deg, #f4ead8, #d8c3a5);
  padding-bottom: 70px;
}

.intro {
  text-align: center;
  padding: 70px 20px;
}

.intro h1 {
  font-size: 4rem;
  margin: 0;
  color: var(--marron);
}

.intro p {
  font-size: 1.2rem;
}

.container {
  max-width: 1100px;
  margin: 50px auto;
  padding: 0 20px;
}

.container h2 {
  text-align: center;
  color: var(--marron);
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 25px;
  margin-top: 30px;
}

.card {
  background: var(--blanc);
  padding: 30px;
  border-radius: 18px;
  text-decoration: none;
  color: var(--texte);
  box-shadow: 0 6px 18px rgba(0,0,0,0.08);
  transition: 0.2s;
}

.card:hover {
  transform: translateY(-5px);
}

.card h3 {
  color: var(--marron);
  font-size: 1.5rem;
}

footer {
  text-align: center;
  padding: 25px;
  color: var(--marron);
}

.page-title {
  text-align: center;
  color: var(--marron);
  font-size: 2.8rem;
  margin-bottom: 10px;
}

.page-subtitle {
  text-align: center;
  font-size: 1.1rem;
  margin-bottom: 40px;
}

.card span {
  display: inline-block;
  margin-top: 15px;
  font-weight: bold;
  color: var(--marron);
}

.chapitres {
  display: grid;
  gap: 20px;
}

.chapitre {
  background: white;
  padding: 25px;
  border-radius: 15px;
}

/* Styles pour accordéon (details/summary) */
/* Accordéon en une seule boîte */
details.chapitre {
  background: white;
  border-radius: 12px;
  box-shadow: 0 6px 18px rgba(0,0,0,0.06);
  overflow: hidden;
}

details.chapitre > summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: bold;
  color: var(--marron);
  background: transparent;
}

details.chapitre > summary::-webkit-details-marker {
  display: none;
}

details.chapitre .contenu-chapitre {
  padding: 14px 20px 18px 20px;
  border-top: 1px solid rgba(0,0,0,0.06);
}

details.chapitre[open] {
  /* garde les coins arrondis quand ouvert */
}

.bouton {
  display: inline-block;
  margin-top: 10px;
  margin-right: 10px;
  padding: 10px 15px;
  background: #4a3428;
  color: white;
  text-decoration: none;
  border-radius: 8px;
}

.bouton.secondaire {
  background: #d8c3a5;
  color: #4a3428;
}