/* UX enhancements — additive only. Uses existing theme tokens, no color/font changes. */
:focus-visible {
  outline: 3px solid var(--brand-primary);
  outline-offset: 2px;
  border-radius: 4px;
}

/* Sticky nav: subtle shadow once scrolled (JS toggles .scrolled) */
.navbar.fixed-top {
  transition: box-shadow var(--transition-base);
}
.navbar.fixed-top.scrolled {
  box-shadow: var(--shadow-lg);
}

/* Active nav link (JS sets .active from pathname) */
.navbar .nav-link.active {
  color: var(--brand-accent) !important;
  font-weight: var(--font-weight-bold);
}

/* Hero readability without the removed gradient overlay: keep photographic
   background untouched, layered text shadow only (no color wash). */
.destination-hero h1,
.destination-hero p.lead,
#home-hero-slider h1,
#home-hero-slider h2,
#home-hero-slider p.lead {
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.8), 0 2px 10px rgba(0, 0, 0, 0.65), 0 4px 24px rgba(0, 0, 0, 0.5);
}

/* Carousel anti-flicker: keep slides on the GPU, no layout work per frame */
.carousel-inner {
  transform: translateZ(0);
}
.carousel-item {
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}
.carousel-item img {
  transform: translateZ(0);
  -webkit-transform: translateZ(0);
}

/* Touch devices: carousel arrows must be visible/tappable */
@media (hover: none) {
  .carousel-control-prev,
  .carousel-control-next {
    opacity: 1;
  }
}

/* Parallax is janky on iOS — fall back to normal scroll */
@media (max-width: 768px) {
  .parallax,
  [style*="background-attachment:fixed"] {
    background-attachment: scroll !important;
  }
  .destination-hero {
    min-height: 70vh !important;
  }
}

/* Back-to-top button (brand accent, theme radius/shadow).
   Opacity/visibility transition instead of display toggle: no layout shift. */
#backToTop {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  z-index: var(--z-fixed);
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: none;
  border-radius: var(--radius-full);
  background: var(--brand-accent);
  color: var(--brand-dark);
  box-shadow: var(--shadow-lg);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 250ms ease, transform 250ms ease, visibility 250ms;
}
#backToTop.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
#backToTop:hover {
  filter: brightness(0.95);
}

/* Card hover: gentle lift only, scoped to program cards (composited transform).
   NOTE: not applied to generic .card to avoid animating large panels. */
.program-card-home {
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  will-change: auto;
}
.program-card-home:hover {
  transform: translateY(-2px);
}

/* Honeypot anti-spam field (JS + server ignore it) */
.hp-field {
  position: absolute !important;
  left: -9999px !important;
  top: auto !important;
  width: 1px !important;
  height: 1px !important;
  overflow: hidden !important;
}

/* Respect users who prefer less motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* FAQ accordion polish (Bootstrap collapse kept, theme tokens only) */
.accordion {
  scroll-margin-top: calc(var(--navbar-height) + 16px);
}
.accordion-button {
  transition: background-color var(--transition-base);
}
.accordion-button:not(.collapsed) {
  background-color: var(--color-gray-50);
}

/* Image loading: static placeholder color + one-shot fade-in.
   NOTE: no infinite shimmer — dozens of simultaneous infinite animations
   jank scrolling on low-end devices. JS fades opacity 0→1 only while the
   image is still loading; loaded/cached images are untouched. */
.gallery-img-wrapper img,
.program-card-home img,
.card-img {
  background-color: var(--color-gray-100);
  transition: opacity 350ms ease;
}
img.ux-fading {
  opacity: 0;
}
img.ux-fading.img-loaded {
  opacity: 1;
}

/* Gallery hover affordance (click opens lightbox) */
a[data-toggle="lightbox"] img,
#destination-gallery img {
  cursor: zoom-in;
}
@media (hover: hover) {
  a[data-toggle="lightbox"] img,
  #destination-gallery img {
    transition: transform var(--transition-base);
  }
  a[data-toggle="lightbox"]:hover img,
  #destination-gallery img:hover {
    transform: scale(1.02);
  }
}

/* Contrast fixes (theme palette untouched):
   - .text-white-50 on brand-color panels fails WCAG for small text. */
.text-white-50 {
  color: rgba(255, 255, 255, 0.85) !important;
}

/* Sticky mobile CTA bar (mobile only) */
#mobileCtaBar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: var(--z-fixed);
  display: none;
  gap: 0.5rem;
  padding: 0.6rem 0.75rem calc(0.6rem + env(safe-area-inset-bottom));
  background: var(--brand-dark);
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.18);
}
@media (max-width: 991.98px) {
  #mobileCtaBar {
    display: flex;
  }
  body {
    padding-bottom: 72px;
  }
}

/* Form submit loading state (JS toggles .is-submitting) */
form.is-submitting button[type="submit"] {
  pointer-events: none;
  opacity: 0.75;
}
form.is-submitting button[type="submit"]::after {
  content: "";
  display: inline-block;
  width: 1em;
  height: 1em;
  margin-left: 0.5em;
  vertical-align: -0.125em;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: ux-spin 0.75s linear infinite;
}
@keyframes ux-spin {
  to {
    transform: rotate(360deg);
  }
}