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

/* Corps principal */
body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background-color: #fff;
  position: relative;
  overflow: hidden;
  font-family: Arial, sans-serif;
}

/* Fond et tourbillon */
.background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  z-index: -1; /* Envoie l'image en arrière-plan */
}

.tourbillon {
  position: absolute;
  width: 50%; /* Augmente la taille */
  height: auto;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.1; /* Rendu subtil */
}

/* Contenu principal */
.content {
  text-align: center;
  z-index: 1; /* S'assure que le contenu reste au-dessus du tourbillon */
}

.logo {
  width: 150px;
  margin-bottom: 20px;
}

h1 {
  font-size: 2rem;
  color: #000;
  margin-bottom: 20px;
  line-height: 1.5;
}

#main-header {
  position: fixed;
  top: -100px; /* Commence en dehors de la vue */
  left: 0;
  width: 100%;
  background: rgba(0, 0, 0, 0.8); /* Fond noir semi-transparent */
  color: white;
  padding: 15px 20px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.5);
  transition: top 0.3s ease; /* Animation pour faire glisser */
  z-index: 1000;
}

#main-header nav a {
  color: white;
  text-decoration: none;
  margin: 0 15px;
}

#main-header nav a:hover {
  text-decoration: underline;
}

button {
  padding: 10px 20px;
  background-color: #000;
  color: #fff;
  border: none;
  border-radius: 5px;
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

button:hover {
  background-color: #444;
}