/* ----- BASE GLOBALE ----- */
html, body {
  margin: 0;
  padding: 0;
  overflow: hidden;
  background: #111b2d; /* Couleur de fond historique */
}

/* ----- ÉCRAN DE LANCEMENT ----- */
#startOverlay {
  position: fixed;
  top: 0; left: 0;
  width: 100vw;
  height: 100vh;
  background: url("assets/intro.jpg") center center no-repeat;
  background-size: cover;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}

#overlayContent {
  background: rgba(0, 0, 0, 0.5);
  padding: 2rem 3rem;
  border-radius: 10px;
  text-align: center;
}

#enterBtn {
  font-size: 1.5rem;
  padding: 1rem 2rem;
  background-color: white;
  color: black;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

/* ----- INTRO VIDÉO ----- */
#intro {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  position: absolute;
  z-index: 10;
  pointer-events: none;
}

/* ----- SCÈNE PRINCIPALE ----- */
#scene {
  width: 100vw;
  height: 100vh;
  position: relative;
  display: none;
  overflow: hidden;
}

/* Calques parallaxe */
.layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
}
.layer img {
  width: 100%;
  height: auto;
  display: block;
}

/* Empilement des plans */
.layer:nth-child(1) { z-index: 50; }  /* plan1.png (le plus proche) */
.layer:nth-child(2) { z-index: 40; }  /* plan2.png */
.layer:nth-child(3) { z-index: 30; }
.layer:nth-child(4) { z-index: 20; }
.layer:nth-child(5) { z-index: 10; }  /* plan5.jpg (le plus éloigné) */

/* Zeppelin */
#zeppelin {
  position: absolute;
  top: 30%;
  width: 200px;
  animation: fly 20s linear infinite;
  z-index: 70;
}
@keyframes fly {
  from { right: -250px; }
  to { right: 110vw; }
}

/* ----- ANIMATIONS VIDÉO ----- */
#animations {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 60;
}

.anim {
  display: none;
  position: absolute;
  height: auto;
  z-index: 61;
}

/* Position et tailles inspirées de la scène Flash 950x550 → adaptatif */
#anim1 {
  width: 14vw;        /* env. 130px */
  top: 8vh;
  right: 10vw;
}

#anim2 {
  width: 18vw;        /* env. 170px */
  top: 35vh;
  left: 5vw;
}

#anim3 {
  width: 24vw;        /* env. 230px */
  bottom: 5vh;
  left: 50%;
  transform: translateX(-50%);
}