/* Reset et base */
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: 0;
  color: #333;
  background-color: #f9f9f9;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 0;
}

/* En-tête */
header {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
  color: white;
  text-align: center;
  padding: 3rem 0;
}

header h1 {
  font-size: 3rem;
  margin: 0;
  font-weight: 300;
}

.subtitle {
  font-size: 1.2rem;
  opacity: 0.8;
  margin-top: 0.5rem;
}

/* Sections */
.section {
  padding: 4rem 0;
}

.light-bg {
  background-color: #f0f4f8;
}

h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: #2c3e50;
  text-align: center;
}

/* Hero section */
.hero {
  background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('assets/background.jpg');
  background-size: cover;
  background-position: center;
  color: white;
  text-align: center;
  padding: 6rem 0;
}

.hero h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: white;
}

.hero p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto 2rem;
}

.btn {
  display: inline-block;
  background: #3498db;
  color: white;
  padding: 0.8rem 1.5rem;
  text-decoration: none;
  border-radius: 4px;
  font-weight: 500;
  transition: background 0.3s;
}

.btn:hover {
  background: #2980b9;
}

/* Grilles */
.content-grid, .prediction-grid, .contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.card, .prediction-card, .contact-card {
  background: white;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover, .prediction-card:hover, .contact-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

.card h3, .prediction-card h3, .contact-card h3 {
  color: #2c3e50;
  margin-top: 0;
  border-bottom: 1px solid #eee;
  padding-bottom: 0.5rem;
}

/* Équations */
.equation-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.equation {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.math {
  font-family: 'Cambria Math', 'Latin Modern Math', 'Times New Roman', serif;
  font-size: 1.5rem;
  text-align: center;
  margin: 1rem 0;
  padding: 0.5rem;
  background: #f8f9fa;
  border-radius: 4px;
}

/* Pied de page */
footer {
  background: #1a1a2e;
  color: white;
  text-align: center;
  padding: 2rem 0;
  margin-top: 2rem;
}

footer a {
  color: #3498db;
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
  header h1 {
    font-size: 2rem;
  }

  .hero h2 {
    font-size: 1.8rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .content-grid, .prediction-grid, .contact-grid {
    grid-template-columns: 1fr;
  }
}