/* ============================================
   Animations: Subtle CSS transitions + scroll reveals
   ============================================ */

/* Scroll-triggered fade in (applied via IntersectionObserver) */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Staggered children */
.fade-in-children > * {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in-children.is-visible > *:nth-child(1) { transition-delay: 0.05s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(2) { transition-delay: 0.1s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(3) { transition-delay: 0.15s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(4) { transition-delay: 0.2s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(5) { transition-delay: 0.25s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(6) { transition-delay: 0.3s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(7) { transition-delay: 0.35s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(8) { transition-delay: 0.4s; opacity: 1; transform: translateY(0); }
.fade-in-children.is-visible > *:nth-child(n+9) { transition-delay: 0.45s; opacity: 1; transform: translateY(0); }

/* Success page checkmark animation */
@keyframes checkmark-circle {
  0% { transform: scale(0); opacity: 0; }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

@keyframes checkmark-draw {
  0% { stroke-dashoffset: 50; }
  100% { stroke-dashoffset: 0; }
}

.success-check {
  animation: checkmark-circle 0.5s ease forwards;
}

.success-check__path {
  stroke-dasharray: 50;
  stroke-dashoffset: 50;
  animation: checkmark-draw 0.4s 0.3s ease forwards;
}

/* Spinner for form submission */
@keyframes spin {
  to { transform: rotate(360deg); }
}

.spinner {
  display: inline-block;
  width: 18px;
  height: 18px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: var(--white);
  border-radius: var(--radius-full);
  animation: spin 0.6s linear infinite;
}

/* Respect user preference */
@media (prefers-reduced-motion: reduce) {
  .fade-in {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .fade-in-children > * {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .success-check,
  .success-check__path {
    animation: none;
    opacity: 1;
    stroke-dashoffset: 0;
    transform: scale(1);
  }

  .spinner {
    animation-duration: 1.5s;
  }
}