html, body {
  margin: 0;
  padding: 0;
  overflow-x: hidden;
  background: #000;
  font-family: sans-serif;
}

.scroll-space {
  height: 4000vh;
}

.scene {
  position: fixed;
  top: 0; left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 1;
  overflow: hidden;
}

.layer {
  position: absolute;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-position: center;
  will-change: transform, opacity;
}

/* Layers */
#sky {
  background-image: url('./assets/sky-7158340_1920.jpg');
  z-index: 1;
}

#clouds1, #clouds2 {
  background-image: url('./assets/cloud.png');
  opacity: 0;
}

#clouds1 { z-index: 2; transform: scale(1.5); }
#clouds2 { z-index: 3; transform: scale(2); }

#gradient-1 {
  background: linear-gradient(to bottom, #87ceeb, #f2e0b6);
  opacity: 0;
  z-index: 4;
}

#downtown {
  background-image: url('./assets/downtown night.jpg');
  z-index: 5;
  transform: scale(1.2);
  opacity: 0;
}

#gradient-2 {
  background: linear-gradient(to bottom, #3e3c3c, #b74d19);
  opacity: 0;
  z-index: 6;
}

#landscape {
  background-image: url('./assets/fall landscape 2 (color).png');
  z-index: 7;
  transform: scale(2);
  opacity: 0;
}

.window-frame {
  background-image: url('./assets/airplane-2620112.png');
  background-size: cover;
  background-position: center;
  position: absolute;
  width: 100%;
  height: 100%;
  z-index: 8;
  will-change: transform, opacity;
}

.overlay-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 3rem;
  color: white;
  z-index: 9;
  text-shadow: 2px 2px 10px rgba(0,0,0,0.6);
}

/* Menu */
#main-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.5s ease;
  background: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(12px);
}

body.show-menu #main-menu {
  opacity: 1;
  pointer-events: auto;
}

.menu-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  color: white;
}

.menu-items {
  list-style: none;
  display: flex;
  gap: 1.5rem;
  align-items: center;
  font-weight: bold;
}

.menu-items a {
  color: white;
  text-decoration: none;
}