/* --- Réinitialisation légère + base --- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --fg-light: #555555;
  --accent: #2563eb; /* bleu professionnel */
  --border: #e5e7eb;
  --card-bg: #fafafa;
  --shadow: rgba(0, 0, 0, 0.05);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f0f0f;
    --fg: #f0f0f0;
    --fg-light: #aaaaaa;
    --card-bg: #1a1a1a;
    --border: #2d2d2d;
    --shadow: rgba(0, 0, 0, 0.2);
  }
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  padding: 0;
}

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

/* --- En-tête --- */
header {
  padding: 2.5rem 0 2rem;
  border-bottom: 1px solid var(--border);
}

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

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--accent);
}

.nav-links a {
  margin-left: 2rem;
  text-decoration: none;
  color: var(--fg-light);
  font-size: 0.95rem;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--fg);
}

/* --- Section principale --- */
main {
  padding: 5rem 0;
}

.hero {
  text-align: center;
  max-width: 700px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 1.25rem;
  letter-spacing: -1px;
}

.hero p {
  font-size: 1.125rem;
  color: var(--fg-light);
  margin-bottom: 2.5rem;
}

.cta-button {
  display: inline-block;
  background-color: var(--accent);
  color: white;
  padding: 0.75rem 2rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  transition: background-color 0.2s, transform 0.1s;
}

.cta-button:hover {
  background-color: #1d4ed8;
  transform: translateY(-2px);
}

.cta-button:active {
  transform: translateY(0);
}

/* --- Section secondaire (fonctionnalités) --- */
.features {
  padding: 4rem 0;
  border-top: 1px solid var(--border);
}

.features .container {
  text-align: center;
}

.features h2 {
  font-size: 1.75rem;
  margin-bottom: 0.5rem;
}

.features p {
  color: var(--fg-light);
  max-width: 600px;
  margin: 0 auto 2rem;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
}

.feature-card {
  background: var(--card-bg);
  padding: 1.75rem;
  border-radius: 8px;
  border: 1px solid var(--border);
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
  font-weight: 700;
}

.feature-card p {
  color: var(--fg-light);
  font-size: 0.95rem;
}

/* --- Pied de page --- */
footer {
  padding: 3rem 0 2rem;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--fg-light);
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    gap: 1.5rem;
  }
  .nav-links a {
    margin: 0 0.75rem;
  }
  .hero h1 {
    font-size: 2rem;
  }
}