/* Performance and Lazy Loading Styles */

/* Lazy Loading Image States */
img.lazy {
  opacity: 1;
  transition: opacity 0.3s ease-in-out;
}

img.loaded {
  opacity: 1;
}

img.loading {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
}

img.error {
  background: #f3f4f6;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #9ca3af;
  font-size: var(--font-size-sm);
}

img.error::after {
  content: "Failed to load image";
}

/* Skeleton Loading Animation */
@keyframes skeleton-loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

/* Enhanced Form Validation */
input.valid {
  border-color: #10b981;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
}

input.invalid {
  border-color: #ef4444;
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

/* Performance Optimizations */
.will-change-transform {
  will-change: transform;
}

.will-change-opacity {
  will-change: opacity;
}

/* Reduce motion for users who prefer it */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .btn-primary {
    border: 2px solid currentColor;
  }

  .btn-outline {
    background: white;
  }
}

/* Print styles */
@media print {
  .header,
  .back-to-top,
  .donation-modal,
  .floating-element {
    display: none !important;
  }

  .hero {
    min-height: auto;
    padding: var(--spacing-8) 0;
  }

  .hero-background {
    display: none;
  }

  * {
    color: black !important;
    background: white !important;
  }
}

/* Optimize font loading */
@font-face {
  font-family: "Inter";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: local("Inter Regular"), local("Inter-Regular");
}

/* Optimize animations for better performance */
.optimized-animation {
  transform: translateZ(0);
  backface-visibility: hidden;
  perspective: 1000px;
}

/* Lazy load sections */
.lazy-section {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.6s ease-out,
    transform 0.6s ease-out;
}

.lazy-section.loaded {
  opacity: 1;
  transform: translateY(0);
}

/* Critical CSS inlining support */
.above-fold {
  /* Styles for above-the-fold content */
  display: block;
}

.below-fold {
  /* Styles for below-the-fold content */
  display: block;
}

.below-fold.loaded {
  display: block;
}

/* Service Worker support indicators */
.sw-update-available {
  position: fixed;
  bottom: var(--spacing-4);
  left: var(--spacing-4);
  background: var(--primary-color);
  color: white;
  padding: var(--spacing-3) var(--spacing-4);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-sm);
  z-index: 1000;
  transform: translateY(100px);
  transition: transform var(--transition-normal);
}

.sw-update-available.show {
  transform: translateY(0);
}

/* Connection-aware loading */
@media (max-width: 768px) and (max-resolution: 150dpi) {
  .low-bandwidth-optimization {
    /* Optimizations for low bandwidth connections */
    background-image: none;
  }
}