/**
 * Lazy Loading Styles for CVCWVUAA Website
 * Provides visual feedback during image loading
 */

/* Lazy loading placeholder */
img[data-src],
img[loading="lazy"],
.lazy-loading {
    background: linear-gradient(
        90deg,
        #f0f0f0 25%,
        #e0e0e0 50%,
        #f0f0f0 75%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
}

/* Shimmer animation for loading state */
@keyframes shimmer {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* Loaded state */
.lazy-loaded {
    animation: fadeIn 0.3s ease-in;
}

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

/* Error state */
.lazy-error {
    background: #f8d7da;
    border: 2px dashed #dc3545;
    padding: 20px;
    text-align: center;
}

.lazy-error::after {
    content: '⚠️ Image failed to load';
    display: block;
    color: #721c24;
    font-size: 14px;
    margin-top: 10px;
}

/* Blur-up effect for progressive loading */
img[data-src].blur-up {
    filter: blur(10px);
    transition: filter 0.3s;
}

img[data-src].blur-up.lazy-loaded {
    filter: blur(0);
}

/* Background image lazy loading */
[data-bg] {
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

[data-bg]:not(.lazy-loaded) {
    background: #f0f0f0;
}

/* Iframe lazy loading */
iframe[data-src] {
    background: #f9f9f9;
    border: 1px solid #ddd;
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    img[data-src],
    .lazy-loading {
        animation: none;
    }
    
    .lazy-loaded {
        animation: none;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    img[data-src],
    img[loading="lazy"],
    .lazy-loading {
        background: linear-gradient(
            90deg,
            #2a2a2a 25%,
            #1a1a1a 50%,
            #2a2a2a 75%
        );
    }
    
    [data-bg]:not(.lazy-loaded) {
        background: #2a2a2a;
    }
}