/* ========================================
   Lazy Loading Styles
   ======================================== */

/* Base styles for lazy elements */
[data-src],
[data-bg],
iframe[data-src] {
  opacity: 0;
  transition: opacity 0.3s ease;
}

/* Ensure normal images are visible */
img:not([data-src]) {
  opacity: 1 !important;
}

/* Loading state */
.lazy-loading {
  position: relative;
  background-color: #f8f9fa;
}

.lazy-loading::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, 
    rgba(255,255,255,0) 0%, 
    rgba(255,255,255,0.2) 20%, 
    rgba(255,255,255,0.5) 60%, 
    rgba(255,255,255,0)
  );
  animation: shimmer 2s infinite;
  z-index: 1;
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

/* Loaded state */
.lazy-loaded {
  opacity: 1;
  animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Error state */
.lazy-error {
  opacity: 1;
  background-color: #f8f9fa;
  background-image: linear-gradient(45deg, #e9ecef 25%, transparent 25%), 
                    linear-gradient(-45deg, #e9ecef 25%, transparent 25%), 
                    linear-gradient(45deg, transparent 75%, #e9ecef 75%), 
                    linear-gradient(-45deg, transparent 75%, #e9ecef 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
  position: relative;
}

.lazy-error::after {
  content: '⚠️';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 2rem;
  z-index: 2;
}

/* Specific styles for different element types */

/* Images */
img.lazy-loading {
  background: linear-gradient(45deg, #f8f9fa 25%, transparent 25%), 
              linear-gradient(-45deg, #f8f9fa 25%, transparent 25%), 
              linear-gradient(45deg, transparent 75%, #f8f9fa 75%), 
              linear-gradient(-45deg, transparent 75%, #f8f9fa 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
  min-height: 200px;
  display: block;
}

/* Background images */
[data-bg].lazy-loading {
  background: linear-gradient(45deg, #f8f9fa 25%, transparent 25%), 
              linear-gradient(-45deg, #f8f9fa 25%, transparent 25%), 
              linear-gradient(45deg, transparent 75%, #f8f9fa 75%), 
              linear-gradient(-45deg, transparent 75%, #f8f9fa 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

/* Iframes */
iframe.lazy-loading {
  background-color: #f8f9fa;
  border: 1px solid #e9ecef;
}

/* Progressive loading blur effect */
img[data-placeholder] {
  filter: blur(5px);
  transform: scale(1.1);
  transition: filter 0.3s ease, transform 0.3s ease;
}

img[data-placeholder].lazy-loaded {
  filter: blur(0);
  transform: scale(1);
}

/* Lazy loading with aspect ratio preservation */
.lazy-aspect-ratio {
  position: relative;
  overflow: hidden;
}

.lazy-aspect-ratio::before {
  content: '';
  display: block;
  padding-bottom: 56.25%; /* 16:9 aspect ratio */
}

.lazy-aspect-ratio img,
.lazy-aspect-ratio iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Different aspect ratios */
.lazy-aspect-ratio.ratio-1-1::before {
  padding-bottom: 100%; /* 1:1 */
}

.lazy-aspect-ratio.ratio-4-3::before {
  padding-bottom: 75%; /* 4:3 */
}

.lazy-aspect-ratio.ratio-3-2::before {
  padding-bottom: 66.666%; /* 3:2 */
}

.lazy-aspect-ratio.ratio-21-9::before {
  padding-bottom: 42.857%; /* 21:9 */
}

/* Performance optimizations */
img[data-src] {
  will-change: opacity, transform;
}

[data-bg] {
  will-change: background-image;
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  .lazy-loading::before {
    animation: none;
  }
  
  .lazy-loaded {
    animation: none;
  }
  
  img[data-placeholder] {
    transition: none;
  }
}

/* High contrast mode */
@media (prefers-contrast: high) {
  .lazy-loading {
    background-color: #000000;
    color: #ffffff;
  }
  
  .lazy-error {
    background-color: #ffffff;
    color: #000000;
    border: 2px solid #000000;
  }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
  .lazy-loading {
    background-color: #2c3e50;
  }
  
  .lazy-loading::before {
    background: linear-gradient(90deg, 
      rgba(255,255,255,0) 0%, 
      rgba(255,255,255,0.1) 20%, 
      rgba(255,255,255,0.2) 60%, 
      rgba(255,255,255,0)
    );
  }
  
  .lazy-error {
    background-color: #34495e;
  }
}

/* Mobile optimizations */
@media (max-width: 768px) {
  .lazy-loading::before {
    animation-duration: 1.5s;
  }
  
  img.lazy-loading {
    min-height: 150px;
  }
}