/* ===== KEYFRAMES ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(2rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes expandCircle {
  from {
    width: 50px;
    height: 50px;
  }
  to {
    width: 120vw;
    height: 120vw;
    border-radius: 0;
  }
}

@keyframes fadeOut {
  to {
    opacity: 0;
  }
}

@keyframes fadeIn {
  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes scroll-down {
  from {
    transform: translateY(0);
  }
  to {
    transform: translateY(50px);
  }
}

@keyframes pulse-ring {
  from {
    transform: scale(1);
    opacity: 1;
  }
  to {
    transform: scale(1.5);
    opacity: 0;
  }
}

/* ===== SCROLL ANIMATION UTILITIES ===== */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(2rem);
}

.animate-on-scroll.visible {
  animation: fadeInUp 0.7s var(--ease-spring) forwards;
  animation-delay: calc(min(var(--index, 0), 4) * 0.1s);
}

/* ===== SECTION ZOOM IN ===== */
.zoom-on-scroll {
  opacity: 0;
  transform: scale(0.95);
  transition: opacity 1.4s ease-out, transform 1.4s var(--ease-spring);
}

.zoom-on-scroll.zoomed {
  opacity: 1;
  transform: scale(1);
}

/* ===== SECTION BACKGROUND TONE VARIATIONS ===== */
.section--tone-1 {
  background: rgba(184, 196, 208, 0.02);
}

.section--tone-2 {
  background: linear-gradient(180deg, transparent 0%, rgba(184, 196, 208, 0.03) 50%, transparent 100%);
}

.section--tone-3 {
  background: rgba(184, 196, 208, 0.015);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

/* ===== NOISE OVERLAY ===== */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  z-index: var(--z-noise);
  pointer-events: none;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px 256px;
}

/* ===== REDUCED MOTION ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}